Dr. Laurie Starkey

Dr. Laurie Starkey

Infrared Spectroscopy, Part I

Slide Duration:

Table of Contents

Section 1: Introduction to Organic Molecules
Introduction and Drawing Structures

49m 51s

Intro
0:00
Organic Chemistry
0:07
Organic
0:08
Inorganic
0:26
Examples of Organic Compounds
1:16
Review Some Chemistry Basics
5:23
Electrons
5:42
Orbitals (s,p,d,f)
6:12
Review Some Chemistry Basics
7:35
Elements & Noble Gases
7:36
Atom & Valance Shell
8:47
Review Some Chemistry Basics
11:33
Electronegative Elements
11:34
Which Is More Electronegative, C or N?
13:45
Ionic & Covalent Bonds
14:07
Ionic Bonds
14:08
Covalent Bonds
16:17
Polar Covalent Bonds
19:35
Polar Covalent Bonds & Electronegativities
19:37
Polarity of Molecules
22:56
Linear molecule
23:07
Bent Molecule
23:53
No Polar Bonds
24:21
Ionic
24:52
Line Drawings
26:36
Line Drawing Overview
26:37
Line Drawing: Example 1
27:12
Line Drawing: Example 2
29:14
Line Drawing: Example 3
29:51
Line Drawing: Example 4
30:34
Line Drawing: Example 5
31:21
Line Drawing: Example 6
32:41
Diversity of Organic Compounds
33:57
Diversity of Organic Compounds
33:58
Diversity of Organic Compounds, cont.
39:16
Diversity of Organic Compounds, cont.
39:17
Examples of Polymers
45:26
Examples of Polymers
45:27
Lewis Structures & Resonance

44m 25s

Intro
0:00
Lewis Structures
0:08
How to Draw a Lewis Structure
0:09
Examples
2:20
Lewis Structures
6:25
Examples: Lewis Structure
6:27
Determining Formal Charges
8:48
Example: Determining Formal Charges for Carbon
10:11
Example: Determining Formal Charges for Oxygen
11:02
Lewis Structures
12:08
Typical, Stable Bonding Patterns: Hydrogen
12:11
Typical, Stable Bonding Patterns: Carbon
12:58
Typical, Stable Bonding Patterns: Nitrogen
13:25
Typical, Stable Bonding Patterns: Oxygen
13:54
Typical, Stable Bonding Patterns: Halogen
14:16
Lewis Structure Example
15:17
Drawing a Lewis Structure for Nitric Acid
15:18
Resonance
21:58
Definition of Resonance
22:00
Delocalization
22:07
Hybrid Structure
22:38
Rules for Estimating Stability of Resonance Structures
26:04
Rule Number 1: Complete Octets
26:10
Rule Number 2: Separation of Charge
28:13
Rule Number 3: Negative and Positive Charges
30:02
Rule Number 4: Equivalent
31:06
Looking for Resonance
32:09
Lone Pair Next to a p Bond
32:10
Vacancy Next to a p Bond
33:53
p Bond Between Two Different Elements
35:00
Other Type of Resonance: Benzene
36:06
Resonance Example
37:29
Draw and Rank Resonance Forms
37:30
Acid-Base Reactions

1h 7m 46s

Intro
0:00
Acid-Base Reactions
0:07
Overview
0:08
Lewis Acid and Lewis Base
0:30
Example 1: Lewis Acid and Lewis Base
1:53
Example 2: Lewis Acid and Lewis Base
3:04
Acid-base Reactions
4:54
Bonsted-Lowry Acid and Bonsted-Lowry Base
4:56
Proton Transfer Reaction
5:36
Acid-Base Equilibrium
8:14
Two Acids in Competition = Equilibrium
8:15
Example: Which is the Stronger Acid?
8:40
Periodic Trends for Acidity
12:40
Across Row
12:41
Periodic Trends for Acidity
19:48
Energy Diagram
19:50
Periodic Trends for Acidity
21:28
Down a Family
21:29
Inductive Effects on Acidity
25:52
Example: Which is the Stronger Acid?
25:54
Other Electron-Withdrawing Group (EWG)
30:37
Inductive Effects on Acidity
32:55
Inductive Effects Decrease with Distance
32:56
Resonance Effects on Acidity
36:35
Examples of Resonance Effects on Acidity
36:36
Resonance Effects on Acidity
41:15
Small and Large Amount of Resonance
41:17
Acid-Base Example
43:10
Which is Most Acidic? Which is the Least Acidic?
43:12
Acid-Base Example
49:26
Which is the Stronger Base?
49:27
Acid-Base Example
53:58
Which is the Strongest Base?
53:59
Common Acids/Bases
1:00:45
Common Acids/Bases
1:00:46
Example: Determine the Direction of Equilibrium
1:04:51
Structures and Properties of Organic Molecules

1h 23m 35s

Intro
0:00
Orbitals and Bonding
0:20
Atomic Orbitals (AO)
0:21
Molecular Orbitals (MO)
1:46
Definition of Molecular Orbitals
1:47
Example 1: Formation of Sigma Bond and Molecular Orbitals
2:20
Molecular Orbitals (MO)
5:25
Example 2: Formation of Pi Bond
5:26
Overlapping E Levels of MO's
7:28
Energy Diagram
7:29
Electronic Transitions
9:18
Electronic Transitions
9:23
Hybrid Orbitals
12:04
Carbon AO
12:06
Hybridization
13:51
Hybrid Orbitals
15:02
Examples of Hybrid Orbitals
15:05
Example: Assign Hybridization
20:31
3-D Sketches
24:05
sp3
24:24
sp2
25:28
sp
27:41
3-D Sketches of Molecules
29:07
3-D Sketches of Molecules 1
29:08
3-D Sketches of Molecules 2
32:29
3-D Sketches of Molecules 3
35:36
3D Sketch
37:20
How to Draw 3D Sketch
37:22
Example 1: Drawing 3D Sketch
37:50
Example 2: Drawing 3D Sketch
43:04
Hybridization and Resonance
46:06
Example: Hybridization and Resonance
46:08
Physical Properties
49:55
Water Solubility, Boiling Points, and Intermolecular Forces
49:56
Types of 'Nonbonding' Interactions
51:47
Dipole-Dipole
52:37
Definition of Dipole-Dipole
52:39
Example: Dipole-Dipole Bonding
53:27
Hydrogen Bonding
57:14
Definition of Hydrogen Bonding
57:15
Example: Hydrogen Bonding
58:05
Van Der Waals/ London Forces
1:03:11
Van Der Waals/ London Forces
1:03:12
Example: Van Der Waals/ London Forces
1:04:59
Water Solubility
1:08:32
Water Solubility
1:08:34
Example: Water Solubility
1:09:05
Example: Acetone
1:11:29
Isomerism
1:13:51
Definition of Isomers
1:13:53
Constitutional Isomers and Example
1:14:17
Stereoisomers and Example
1:15:34
Introduction to Functional Groups
1:17:06
Functional Groups: Example, Abbreviation, and Name
1:17:07
Introduction to Functional Groups
1:20:48
Functional Groups: Example, Abbreviation, and Name
1:20:49
Alkane Structures

1h 13m 38s

Intro
0:00
Nomenclature of Alkanes
0:12
Nomenclature of Alkanes and IUPAC Rules
0:13
Examples: Nomenclature of Alkanes
4:38
Molecular Formula and Degrees of Unsaturation (DU)
17:24
Alkane Formula
17:25
Example: Heptane
17:58
Why '2n+2' Hydrogens?
18:35
Adding a Ring
19:20
Adding a p Bond
19:42
Example 1: Determine Degrees of Unsaturation (DU)
20:17
Example 2: Determine Degrees of Unsaturation (DU)
21:35
Example 3: Determine DU of Benzene
23:30
Molecular Formula and Degrees of Unsaturation (DU)
24:41
Example 4: Draw Isomers
24:42
Physical properties of Alkanes
29:17
Physical properties of Alkanes
29:18
Conformations of Alkanes
33:40
Conformational Isomers
33:42
Conformations of Ethane: Eclipsed and Staggered
34:40
Newman Projection of Ethane
36:15
Conformations of Ethane
40:38
Energy and Degrees Rotated Diagram
40:41
Conformations of Butane
42:28
Butane
42:29
Newman Projection of Butane
43:35
Conformations of Butane
44:25
Energy and Degrees Rotated Diagram
44:30
Cycloalkanes
51:26
Cyclopropane and Cyclobutane
51:27
Cyclopentane
53:56
Cycloalkanes
54:56
Cyclohexane: Chair, Boat, and Twist Boat Conformations
54:57
Drawing a Cyclohexane Chair
57:58
Drawing a Cyclohexane Chair
57:59
Newman Projection of Cyclohexane
1:02:14
Cyclohexane Chair Flips
1:04:06
Axial and Equatorial Groups
1:04:10
Example: Chair Flip on Methylcyclohexane
1:06:44
Cyclohexane Conformations Example
1:09:01
Chair Conformations of cis-1-t-butyl-4-methylcyclohexane
1:09:02
Stereochemistry

1h 40m 54s

Intro
0:00
Stereochemistry
0:10
Isomers
0:11
Stereoisomer Examples
1:30
Alkenes
1:31
Cycloalkanes
2:35
Stereoisomer Examples
4:00
Tetrahedral Carbon: Superimposable (Identical)
4:01
Tetrahedral Carbon: Non-Superimposable (Stereoisomers)
5:18
Chirality
7:18
Stereoisomers
7:19
Chiral
8:05
Achiral
8:29
Example: Achiral and Chiral
8:45
Chirality
20:11
Superimposable, Non-Superimposable, Chiral, and Achiral
20:12
Nomenclature
23:00
Cahn-Ingold-Prelog Rules
23:01
Nomenclature
29:39
Example 1: Nomenclature
29:40
Example 2: Nomenclature
31:49
Example 3: Nomenclature
33:24
Example 4: Nomenclature
35:39
Drawing Stereoisomers
36:58
Drawing (S)-2-bromopentane
36:59
Drawing the Enantiomer of (S)-2-bromopentane: Method 1
38:47
Drawing the Enantiomer of (S)-2-bromopentane: Method 2
39:35
Fischer Projections
41:47
Definition of Fischer Projections
41:49
Drawing Fischer Projection
43:43
Use of Fisher Projection: Assigning Configuration
49:13
Molecules with Two Chiral Carbons
51:49
Example A
51:42
Drawing Enantiomer of Example A
53:26
Fischer Projection of A
54:25
Drawing Stereoisomers, cont.
59:40
Drawing Stereoisomers Examples
59:41
Diastereomers
1:01:48
Drawing Stereoisomers
1:06:37
Draw All Stereoisomers of 2,3-dichlorobutane
1:06:38
Molecules with Two Chiral Centers
1:10:22
Draw All Stereoisomers of 2,3-dichlorobutane, cont.
1:10:23
Optical Activity
1:14:10
Chiral Molecules
1:14:11
Angle of Rotation
1:14:51
Achiral Species
1:16:46
Physical Properties of Stereoisomers
1:17:11
Enantiomers
1:17:12
Diastereomers
1:18:01
Example
1:18:26
Physical Properties of Stereoisomers
1:23:05
When Do Enantiomers Behave Differently?
1:23:06
Racemic Mixtures
1:28:18
Racemic Mixtures
1:28:21
Resolution
1:29:52
Unequal Mixtures of Enantiomers
1:32:54
Enantiomeric Excess (ee)
1:32:55
Unequal Mixture of Enantiomers
1:34:43
Unequal Mixture of Enantiomers
1:34:44
Example: Finding ee
1:36:38
Example: Percent of Composition
1:39:46
Section 2: Understanding Organic Reactions
Nomenclature

1h 53m 47s

Intro
0:00
Cycloalkane Nomenclature
0:17
Cycloalkane Nomenclature and Examples
0:18
Alkene Nomenclature
6:28
Alkene Nomenclature and Examples
6:29
Alkene Nomenclature: Stereochemistry
15:07
Alkenes With Two Groups: Cis & Trans
15:08
Alkenes With Greater Than Two Groups: E & Z
18:26
Alkyne Nomenclature
24:46
Alkyne Nomenclature and Examples
24:47
Alkane Has a Higher Priority Than Alkyne
28:25
Alcohol Nomenclature
29:24
Alcohol Nomenclature and Examples
29:25
Alcohol FG Has Priority Over Alkene/yne
33:41
Ether Nomenclature
36:32
Ether Nomenclature and Examples
36:33
Amine Nomenclature
42:59
Amine Nomenclature and Examples
43:00
Amine Nomenclature
49:45
Primary, Secondary, Tertiary, Quaternary Salt
49:46
Aldehyde Nomenclature
51:37
Aldehyde Nomenclature and Examples
51:38
Ketone Nomenclature
58:43
Ketone Nomenclature and Examples
58:44
Aromatic Nomenclature
1:05:02
Aromatic Nomenclature and Examples
1:05:03
Aromatic Nomenclature, cont.
1:09:09
Ortho, Meta, and Para
1:09:10
Aromatic Nomenclature, cont.
1:13:27
Common Names for Simple Substituted Aromatic Compounds
1:13:28
Carboxylic Acid Nomenclature
1:16:35
Carboxylic Acid Nomenclature and Examples
1:16:36
Carboxylic Acid Derivatives
1:22:28
Carboxylic Acid Derivatives
1:22:42
General Structure
1:23:10
Acid Halide Nomenclature
1:24:48
Acid Halide Nomenclature and Examples
1:24:49
Anhydride Nomenclature
1:28:10
Anhydride Nomenclature and Examples
1:28:11
Ester Nomenclature
1:32:50
Ester Nomenclature
1:32:51
Carboxylate Salts
1:38:51
Amide Nomenclature
1:40:02
Amide Nomenclature and Examples
1:40:03
Nitrile Nomenclature
1:45:22
Nitrile Nomenclature and Examples
1:45:23
Chemical Reactions

51m 1s

Intro
0:00
Chemical Reactions
0:06
Reactants and Products
0:07
Thermodynamics
0:50
Equilibrium Constant
1:06
Equation
2:35
Organic Reaction
3:05
Energy vs. Progress of Rxn Diagrams
3:48
Exothermic Reaction
4:02
Endothermic Reaction
6:54
Estimating ΔH rxn
9:15
Bond Breaking
10:03
Bond Formation
10:25
Bond Strength
11:35
Homolytic Cleavage
11:59
Bond Dissociation Energy (BDE) Table
12:29
BDE for Multiple Bonds
14:32
Examples
17:35
Kinetics
20:35
Kinetics
20:36
Examples
21:49
Reaction Rate Variables
23:15
Reaction Rate Variables
23:16
Increasing Temperature, Increasing Rate
24:08
Increasing Concentration, Increasing Rate
25:39
Decreasing Energy of Activation, Increasing Rate
27:49
Two-Step Mechanisms
30:06
E vs. POR Diagram (2-step Mechanism)
30:07
Reactive Intermediates
33:03
Reactive Intermediates
33:04
Example: A Carbocation
35:20
Carbocation Stability
37:24
Relative Stability of Carbocation
37:25
Alkyl groups and Hyperconjugation
38:45
Carbocation Stability
41:57
Carbocation Stabilized by Resonance: Allylic
41:58
Carbocation Stabilized by Resonance: Benzylic
42:59
Overall Carbocation Stability
44:05
Free Radicals
45:05
Definition and Examples of Free Radicals
45:06
Radical Mechanisms
49:40
Example: Regular Arrow
49:41
Example: Fish-Hook Arrow
50:17
Free Radical Halogenation

26m 23s

Intro
0:00
Free Radical Halogenation
0:06
Free Radical Halogenation
0:07
Mechanism: Initiation
1:27
Mechanism: Propagation Steps
2:21
Free Radical Halogenation
5:33
Termination Steps
5:36
Example 1: Terminations Steps
6:00
Example 2: Terminations Steps
6:18
Example 3: Terminations Steps
7:43
Example 4: Terminations Steps
8:04
Regiochemistry of Free Radical Halogenation
9:32
Which Site/Region Reacts and Why?
9:34
Bromination and Rate of Reaction
14:03
Regiochemistry of Free Radical Halogenation
14:30
Chlorination
14:31
Why the Difference in Selectivity?
19:58
Allylic Halogenation
20:53
Examples of Allylic Halogenation
20:55
Substitution Reactions

1h 48m 5s

Intro
0:00
Substitution Reactions
0:06
Substitution Reactions Example
0:07
Nucleophile
0:39
Electrophile
1:20
Leaving Group
2:56
General Reaction
4:13
Substitution Reactions
4:43
General Reaction
4:46
Substitution Reaction Mechanisms: Simultaneous
5:08
Substitution Reaction Mechanisms: Stepwise
5:34
SN2 Substitution
6:21
Example of SN2 Mechanism
6:22
SN2 Kinetics
7:58
Rate of SN2
9:10
Sterics Affect Rate of SN2
9:12
Rate of SN2 (By Type of RX)
14:13
SN2: E vs. POR Diagram
17:26
E vs. POR Diagram
17:27
Transition State (TS)
18:24
SN2 Transition State, Kinetics
20:58
SN2 Transition State, Kinetics
20:59
Hybridization of TS Carbon
21:57
Example: Allylic LG
23:34
Stereochemistry of SN2
25:46
Backside Attack and Inversion of Stereochemistry
25:48
SN2 Summary
29:56
Summary of SN2
29:58
Predict Products (SN2)
31:42
Example 1: Predict Products
31:50
Example 2: Predict Products
33:38
Example 3: Predict Products
35:11
Example 4: Predict Products
36:11
Example 5: Predict Products
37:32
SN1 Substitution Mechanism
41:52
Is This Substitution? Could This Be an SN2 Mechanism?
41:54
SN1 Mechanism
43:50
Two Key Steps: 1. Loss of LG
43:53
Two Key Steps: 2. Addition of nu
45:11
SN1 Kinetics
47:17
Kinetics of SN1
47:18
Rate of SN1 (By RX type)
48:44
SN1 E vs. POR Diagram
49:49
E vs. POR Diagram
49:51
First Transition Stage (TS-1)
51:48
Second Transition Stage (TS-2)
52:56
Stereochemistry of SN1
53:44
Racemization of SN1 and Achiral Carbocation Intermediate
53:46
Example
54:29
SN1 Summary
58:25
Summary of SN1
58:26
SN1 or SN2 Mechanisms?
1:00:40
Example 1: SN1 or SN2 Mechanisms
1:00:42
Example 2: SN1 or SN2 Mechanisms
1:03:00
Example 3: SN1 or SN2 Mechanisms
1:04:06
Example 4: SN1 or SN2 Mechanisms
1:06:17
SN1 Mechanism
1:09:12
Three Steps of SN1 Mechanism
1:09:13
SN1 Carbocation Rearrangements
1:14:50
Carbocation Rearrangements Example
1:14:51
SN1 Carbocation Rearrangements
1:20:46
Alkyl Groups Can Also Shift
1:20:48
Leaving Groups
1:24:26
Leaving Groups
1:24:27
Forward or Reverse Reaction Favored?
1:26:00
Leaving Groups
1:29:59
Making poor LG Better: Method 1
1:30:00
Leaving Groups
1:34:18
Making poor LG Better: Tosylate (Method 2)
1:34:19
Synthesis Problem
1:38:15
Example: Provide the Necessary Reagents
1:38:16
Nucleophilicity
1:41:10
What Makes a Good Nucleophile?
1:41:11
Nucleophilicity
1:44:45
Periodic Trends: Across Row
1:44:47
Periodic Trends: Down a Family
1:46:46
Elimination Reactions

1h 11m 43s

Intro
0:00
Elimination Reactions: E2 Mechanism
0:06
E2 Mechanism
0:08
Example of E2 Mechanism
1:01
Stereochemistry of E2
4:48
Anti-Coplanar & Anti-Elimination
4:50
Example 1: Stereochemistry of E2
5:34
Example 2: Stereochemistry of E2
10:39
Regiochemistry of E2
13:04
Refiochemistry of E2 and Zaitsev's Rule
13:05
Alkene Stability
17:39
Alkene Stability
19:20
Alkene Stability Examples
19:22
Example 1: Draw Both E2 Products and Select Major
21:57
Example 2: Draw Both E2 Products and Select Major
25:02
SN2 Vs. E2 Mechanisms
29:06
SN2 Vs. E2 Mechanisms
29:07
When Do They Compete?
30:34
SN2 Vs. E2 Mechanisms
31:23
Compare Rates
31:24
SN2 Vs. E2 Mechanisms
36:34
t-BuBr: What If Vary Base?
36:35
Preference for E2 Over SN2 (By RX Type)
40:42
E1 Elimination Mechanism
41:51
E1 - Elimination Unimolecular
41:52
E1 Mechanism: Step 1
44:14
E1 Mechanism: Step 2
44:48
E1 Kinetics
46:58
Rate = k[RCI]
47:00
E1 Rate (By Type of Carbon Bearing LG)
48:31
E1 Stereochemistry
49:49
Example 1: E1 Stereochemistry
49:51
Example 2: E1 Stereochemistry
52:31
Carbocation Rearrangements
55:57
Carbocation Rearrangements
56:01
Product Mixtures
57:20
Predict the Product: SN2 vs. E2
59:58
Example 1: Predict the Product
1:00:00
Example 2: Predict the Product
1:02:10
Example 3: Predict the Product
1:04:07
Predict the Product: SN2 vs. E2
1:06:06
Example 4: Predict the Product
1:06:07
Example 5: Predict the Product
1:07:29
Example 6: Predict the Product
1:07:51
Example 7: Predict the Product
1:09:18
Section 3: Alkanes, Alkenes, & Alkynes
Alkenes

36m 39s

Intro
0:00
Alkenes
0:12
Definition and Structure of Alkenes
0:13
3D Sketch of Alkenes
1:53
Pi Bonds
3:48
Alkene Stability
4:57
Alkyl Groups Attached
4:58
Trans & Cis
6:20
Alkene Stability
8:42
Pi Bonds & Conjugation
8:43
Bridgehead Carbons & Bredt's Rule
10:22
Measuring Stability: Hydrogenation Reaction
11:40
Alkene Synthesis
12:01
Method 1: E2 on Alkyl Halides
12:02
Review: Stereochemistry
16:17
Review: Regiochemistry
16:50
Review: SN2 vs. E2
17:34
Alkene Synthesis
18:57
Method 2: Dehydration of Alcohols
18:58
Mechanism
20:08
Alkene Synthesis
23:26
Alcohol Dehydration
23:27
Example 1: Comparing Strong Acids
26:59
Example 2: Mechanism for Dehydration Reaction
29:00
Example 3: Transform
32:50
Reactions of Alkenes

2h 8m 44s

Intro
0:00
Reactions of Alkenes
0:05
Electrophilic Addition Reaction
0:06
Addition of HX
2:02
Example: Regioselectivity & 2 Steps Mechanism
2:03
Markovnikov Addition
5:30
Markovnikov Addition is Favored
5:31
Graph: E vs. POR
6:33
Example
8:29
Example: Predict and Consider the Stereochemistry
8:30
Hydration of Alkenes
12:31
Acid-catalyzed Addition of Water
12:32
Strong Acid
14:20
Hydration of Alkenes
15:20
Acid-catalyzed Addition of Water: Mechanism
15:21
Hydration vs. Dehydration
19:51
Hydration Mechanism is Exact Reverse of Dehydration
19:52
Example
21:28
Example: Hydration Reaction
21:29
Alternative 'Hydration' Methods
25:26
Oxymercuration-Demercuration
25:27
Oxymercuration Mechanism
28:55
Mechanism of Oxymercuration
28:56
Alternative 'Hydration' Methods
30:51
Hydroboration-Oxidation
30:52
Hydroboration Mechanism
33:22
1-step (concerted)
33:23
Regioselective
34:45
Stereoselective
35:30
Example
35:58
Example: Hydroboration-Oxidation
35:59
Example
40:42
Example: Predict the Major Product
40:43
Synthetic Utility of 'Alternate' Hydration Methods
44:36
Example: Synthetic Utility of 'Alternate' Hydration Methods
44:37
Flashcards
47:28
Tips On Using Flashcards
47:29
Bromination of Alkenes
49:51
Anti-Addition of Br₂
49:52
Bromination Mechanism
53:16
Mechanism of Bromination
53:17
Bromination Mechanism
55:42
Mechanism of Bromination
55:43
Bromination: Halohydrin Formation
58:54
Addition of other Nu: to Bromonium Ion
58:55
Mechanism
1:00:08
Halohydrin: Regiochemistry
1:03:55
Halohydrin: Regiochemistry
1:03:56
Bromonium Ion Intermediate
1:04:26
Example
1:09:28
Example: Predict Major Product
1:09:29
Example Cont.
1:10:59
Example: Predict Major Product Cont.
1:11:00
Catalytic Hydrogenation of Alkenes
1:13:19
Features of Catalytic Hydrogenation
1:13:20
Catalytic Hydrogenation of Alkenes
1:14:48
Metal Surface
1:14:49
Heterogeneous Catalysts
1:15:29
Homogeneous Catalysts
1:16:08
Catalytic Hydrogenation of Alkenes
1:17:44
Hydrogenation & Pi Bond Stability
1:17:45
Energy Diagram
1:19:22
Catalytic Hydrogenation of Dienes
1:20:40
Hydrogenation & Pi Bond Stability
1:20:41
Energy Diagram
1:23:31
Example
1:24:14
Example: Predict Product
1:24:15
Oxidation of Alkenes
1:27:21
Redox Review
1:27:22
Epoxide
1:30:26
Diol (Glycol)
1:30:54
Ketone/ Aldehyde
1:31:13
Epoxidation
1:32:08
Epoxidation
1:32:09
General Mechanism
1:36:32
Alternate Epoxide Synthesis
1:37:38
Alternate Epoxide Synthesis
1:37:39
Dihydroxylation
1:41:10
Dihydroxylation
1:41:12
General Mechanism (Concerted Via Cycle Intermediate)
1:42:38
Ozonolysis
1:44:22
Ozonolysis: Introduction
1:44:23
Ozonolysis: Is It Good or Bad?
1:45:05
Ozonolysis Reaction
1:48:54
Examples
1:51:10
Example 1: Ozonolysis
1:51:11
Example
1:53:25
Radical Addition to Alkenes
1:55:05
Recall: Free-Radical Halogenation
1:55:15
Radical Mechanism
1:55:45
Propagation Steps
1:58:01
Atom Abstraction
1:58:30
Addition to Alkene
1:59:11
Radical Addition to Alkenes
1:59:54
Markovnivok (Electrophilic Addition) & anti-Mark. (Radical Addition)
1:59:55
Mechanism
2:01:03
Alkene Polymerization
2:05:35
Example: Alkene Polymerization
2:05:36
Alkynes

1h 13m 19s

Intro
0:00
Structure of Alkynes
0:04
Structure of Alkynes
0:05
3D Sketch
2:30
Internal and Terminal
4:03
Reductions of Alkynes
4:36
Catalytic Hydrogenation
4:37
Lindlar Catalyst
5:25
Reductions of Alkynes
7:24
Dissolving Metal Reduction
7:25
Oxidation of Alkynes
9:24
Ozonolysis
9:25
Reactions of Alkynes
10:56
Addition Reactions: Bromination
10:57
Addition of HX
12:24
Addition of HX
12:25
Addition of HX
13:36
Addition of HX: Mechanism
13:37
Example
17:38
Example: Transform
17:39
Hydration of Alkynes
23:35
Hydration of Alkynes
23:36
Hydration of Alkynes
26:47
Hydration of Alkynes: Mechanism
26:49
'Hydration' via Hydroboration-Oxidation
32:57
'Hydration' via Hydroboration-Oxidation
32:58
Disiamylborane
33:28
Hydroboration-Oxidation Cont.
34:25
Alkyne Synthesis
36:17
Method 1: Alkyne Synthesis By Dehydrohalogenation
36:19
Alkyne Synthesis
39:06
Example: Transform
39:07
Alkyne Synthesis
41:21
Method 2 & Acidity of Alkynes
41:22
Conjugate Bases
43:06
Preparation of Acetylide Anions
49:55
Preparation of Acetylide Anions
49:57
Alkyne Synthesis
53:40
Synthesis Using Acetylide Anions
53:41
Example 1: Transform
57:04
Example 2: Transform
1:01:07
Example 3: Transform
1:06:22
Section 4: Alcohols
Alcohols, Part I

59m 52s

Intro
0:00
Alcohols
0:11
Attributes of Alcohols
0:12
Boiling Points
2:00
Water Solubility
5:00
Water Solubility (Like Dissolves Like)
5:01
Acidity of Alcohols
9:39
Comparison of Alcohols Acidity
9:41
Preparation of Alkoxides
13:03
Using Strong Base Like Sodium Hydride
13:04
Using Redox Reaction
15:36
Preparation of Alkoxides
17:41
Using K°
17:42
Phenols Are More Acidic Than Other Alcohols
19:51
Synthesis of Alcohols, ROH
21:43
Synthesis of Alcohols from Alkyl Halides, RX (SN2 or SN1)
21:44
Synthesis of Alcohols, ROH
25:08
Unlikely on 2° RX (E2 Favored)
25:09
Impossible on 3° RX (E2) and Phenyl/Vinyl RX (N/R)
25:47
Synthesis of Alcohols, ROH
26:26
SN1 with H₂O 'Solvolysis' or 'Hydrolysis'
26:27
Carbocation Can Rearrange
29:00
Synthesis of Alcohols, ROH
30:08
Synthesis of Alcohols From Alkenes: Hydration
30:09
Synthesis of Alcohols From Alkenes: Oxidation/Diol
32:20
Synthesis of Alcohols, ROH
33:14
Synthesis of Alcohols From Ketones and Aldehydes
33:15
Organometallic Reagents: Preparation
37:03
Grignard (RMgX)
37:04
Organolithium (Rli)
40:03
Organometallic Reagents: Reactions
41:45
Reactions of Organometallic Reagents
41:46
Organometallic Reagents: Reactions as Strong Nu:
46:40
Example 1: Reactions as Strong Nu:
46:41
Example 2: Reactions as Strong Nu:
48:57
Hydride Nu:
50:52
Hydride Nu:
50:53
Examples
53:34
Predict 1
53:35
Predict 2
54:45
Examples
56:43
Transform
56:44
Provide Starting Material
58:18
Alcohols, Part II

45m 35s

Intro
0:00
Oxidation Reactions
0:08
Oxidizing Agents: Jones, PCC, Swern
0:09
'Jones' Oxidation
0:43
Example 1: Predict Oxidation Reactions
2:29
Example 2: Predict Oxidation Reactions
3:00
Oxidation Reactions
4:11
Selective Oxidizing Agents (PCC and Swern)
4:12
PCC (Pyridiniym Chlorochromate)
5:10
Swern Oxidation
6:05
General [ox] Mechanism
8:32
General [ox] Mechanism
8:33
Oxidation of Alcohols
10:11
Example 1: Oxidation of Alcohols
10:12
Example 2: Oxidation of Alcohols
11:20
Example 3: Oxidation of Alcohols
11:46
Example
13:09
Predict: PCC Oxidation Reactions
13:10
Tosylation of Alcohols
15:22
Introduction to Tosylation of Alcohols
15:23
Example
21:08
Example: Tosylation of Alcohols
21:09
Reductions of Alcohols
23:39
Reductions of Alcohols via SN2 with Hydride
24:22
Reductions of Alcohols via Dehydration
27:12
Conversion of Alcohols to Alkyl Halides
30:12
Conversion of Alcohols to Alkyl Halides via Tosylate
30:13
Conversion of Alcohols to Alkyl Halides
31:17
Using HX
31:18
Mechanism
32:09
Conversion of Alcohols to Alkyl Halides
35:43
Reagents that Provide LG and Nu: in One 'Pot'
35:44
General Mechanisms
37:44
Example 1: General Mechanisms
37:45
Example 2: General Mechanisms
39:25
Example
41:04
Transformation of Alcohols
41:05
Section 5: Ethers, Thiols, Thioethers, & Ketones
Ethers

1h 34m 45s

Intro
0:00
Ethers
0:11
Overview of Ethers
0:12
Boiling Points
1:37
Ethers
4:34
Water Solubility (Grams per 100mL H₂O)
4:35
Synthesis of Ethers
7:53
Williamson Ether Synthesis
7:54
Example: Synthesis of Ethers
9:23
Synthesis of Ethers
10:27
Example: Synthesis of Ethers
10:28
Intramolecular SN2
13:04
Planning an Ether Synthesis
14:45
Example 1: Planning an Ether Synthesis
14:46
Planning an Ether Synthesis
16:16
Example 2: Planning an Ether Synthesis
16:17
Planning an Ether Synthesis
22:04
Example 3: Synthesize Dipropyl Ether
22:05
Planning an Ether Synthesis
26:01
Example 4: Transform
26:02
Synthesis of Epoxides
30:05
Synthesis of Epoxides Via Williamson Ether Synthesis
30:06
Synthesis of Epoxides Via Oxidation
32:42
Reaction of Ethers
33:35
Reaction of Ethers
33:36
Reactions of Ethers with HBr or HI
34:44
Reactions of Ethers with HBr or HI
34:45
Mechanism
35:25
Epoxide Ring-Opening Reaction
39:25
Epoxide Ring-Opening Reaction
39:26
Example: Epoxide Ring-Opening Reaction
42:42
Acid-Catalyzed Epoxide Ring Opening
44:16
Acid-Catalyzed Epoxide Ring Opening Mechanism
44:17
Acid-Catalyzed Epoxide Ring Opening
50:13
Acid-Catalyzed Epoxide Ring Opening Mechanism
50:14
Catalyst Needed for Ring Opening
53:34
Catalyst Needed for Ring Opening
53:35
Stereochemistry of Epoxide Ring Opening
55:56
Stereochemistry: SN2 Mechanism
55:57
Acid or Base Mechanism?
58:30
Example
1:01:03
Transformation
1:01:04
Regiochemistry of Epoxide Ring Openings
1:05:29
Regiochemistry of Epoxide Ring Openings in Base
1:05:30
Regiochemistry of Epoxide Ring Openings in Acid
1:07:34
Example
1:10:26
Example 1: Epoxide Ring Openings in Base
1:10:27
Example 2: Epoxide Ring Openings in Acid
1:12:50
Reactions of Epoxides with Grignard and Hydride
1:15:35
Reactions of Epoxides with Grignard and Hydride
1:15:36
Example
1:21:47
Example: Ethers
1:21:50
Example
1:27:01
Example: Synthesize
1:27:02
Thiols and Thioethers

16m 50s

Intro
0:00
Thiols and Thioethers
0:10
Physical Properties
0:11
Reactions Can Be Oxidized
2:16
Acidity of Thiols
3:11
Thiols Are More Acidic Than Alcohols
3:12
Synthesis of Thioethers
6:44
Synthesis of Thioethers
6:45
Example
8:43
Example: Synthesize the Following Target Molecule
8:44
Example
14:18
Example: Predict
14:19
Ketones

2h 18m 12s

Intro
0:00
Aldehydes & Ketones
0:11
The Carbonyl: Resonance & Inductive
0:12
Reactivity
0:50
The Carbonyl
2:35
The Carbonyl
2:36
Carbonyl FG's
4:10
Preparation/Synthesis of Aldehydes & Ketones
6:18
Oxidation of Alcohols
6:19
Ozonolysis of Alkenes
7:16
Hydration of Alkynes
8:01
Reaction with Hydride Nu:
9:00
Reaction with Hydride Nu:
9:01
Reaction with Carbon Nu:
11:29
Carbanions: Acetylide
11:30
Carbanions: Cyanide
14:23
Reaction with Carbon Nu:
15:32
Organometallic Reagents (RMgX, Rli)
15:33
Retrosynthesis of Alcohols
17:04
Retrosynthesis of Alcohols
17:05
Example
19:30
Example: Transform
19:31
Example
22:57
Example: Transform
22:58
Example
28:19
Example: Transform
28:20
Example
33:36
Example: Transform
33:37
Wittig Reaction
37:39
Wittig Reaction: A Resonance-Stabilized Carbanion (Nu:)
37:40
Wittig Reaction: Mechanism
39:51
Preparation of Wittig Reagent
41:58
Two Steps From RX
41:59
Example: Predict
45:02
Wittig Retrosynthesis
46:19
Wittig Retrosynthesis
46:20
Synthesis
48:09
Reaction with Oxygen Nu:
51:21
Addition of H₂O
51:22
Exception: Formaldehyde is 99% Hydrate in H₂O Solution
54:10
Exception: Hydrate is Favored if Partial Positive Near Carbonyl
55:26
Reaction with Oxygen Nu:
57:45
Addition of ROH
57:46
TsOH: Tosic Acid
58:28
Addition of ROH Cont.
59:09
Example
1:01:43
Predict
1:01:44
Mechanism
1:03:08
Mechanism for Acetal Formation
1:04:10
Mechanism for Acetal Formation
1:04:11
What is a CTI?
1:15:04
Tetrahedral Intermediate
1:15:05
Charged Tetrahedral Intermediate
1:15:45
CTI: Acid-cat
1:16:10
CTI: Base-cat
1:17:01
Acetals & Cyclic Acetals
1:17:49
Overall
1:17:50
Cyclic Acetals
1:18:46
Hydrolysis of Acetals: Regenerates Carbonyl
1:20:01
Hydrolysis of Acetals: Regenerates Carbonyl
1:20:02
Mechanism
1:22:08
Reaction with Nitrogen Nu:
1:30:11
Reaction with Nitrogen Nu:
1:30:12
Example
1:32:18
Mechanism of Imine Formation
1:33:24
Mechanism of Imine Formation
1:33:25
Oxidation of Aldehydes
1:38:12
Oxidation of Aldehydes 1
1:38:13
Oxidation of Aldehydes 2
1:39:52
Oxidation of Aldehydes 3
1:40:10
Reductions of Ketones and Aldehydes
1:40:54
Reductions of Ketones and Aldehydes
1:40:55
Hydride/ Workup
1:41:22
Raney Nickel
1:42:07
Reductions of Ketones and Aldehydes
1:43:24
Clemmensen Reduction & Wolff-Kishner Reduction
1:43:40
Acetals as Protective Groups
1:46:50
Acetals as Protective Groups
1:46:51
Example
1:50:39
Example: Consider the Following Synthesis
1:50:40
Protective Groups
1:54:47
Protective Groups
1:54:48
Example
1:59:02
Example: Transform
1:59:03
Example: Another Route
2:04:54
Example: Transform
2:08:49
Example
2:08:50
Transform
2:08:51
Example
2:11:05
Transform
2:11:06
Example
2:13:45
Transform
2:13:46
Example
2:15:43
Provide the Missing Starting Material
2:15:44
Section 6: Organic Transformation Practice
Transformation Practice Problems

38m 58s

Intro
0:00
Practice Problems
0:33
Practice Problem 1: Transform
0:34
Practice Problem 2: Transform
3:57
Practice Problems
7:49
Practice Problem 3: Transform
7:50
Practice Problems
15:32
Practice Problem 4: Transform
15:34
Practice Problem 5: Transform
20:15
Practice Problems
24:08
Practice Problem 6: Transform
24:09
Practice Problem 7: Transform
29:27
Practice Problems
33:08
Practice Problem 8: Transform
33:09
Practice Problem 9: Transform
35:23
Section 7: Carboxylic Acids
Carboxylic Acids

1h 17m 51s

Intro
0:00
Review Reactions of Ketone/Aldehyde
0:06
Carbonyl Reactivity
0:07
Nu: = Hydride (Reduction)
1:37
Nu: = Grignard
2:08
Review Reactions of Ketone/Aldehyde
2:53
Nu: = Alcohol
2:54
Nu: = Amine
3:46
Carboxylic Acids and Their Derivatives
4:37
Carboxylic Acids and Their Derivatives
4:38
Ketone vs. Ester Reactivity
6:33
Ketone Reactivity
6:34
Ester Reactivity
6:55
Carboxylic Acids and Their Derivatives
7:30
Acid Halide, Anhydride, Ester, Amide, and Nitrile
7:43
General Reactions of Acarboxylic Acid Derivatives
9:22
General Reactions of Acarboxylic Acid Derivatives
9:23
Physical Properties of Carboxylic Acids
12:16
Acetic Acid
12:17
Carboxylic Acids
15:46
Aciditiy of Carboxylic Acids, RCO₂H
17:45
Alcohol
17:46
Carboxylic Acid
19:21
Aciditiy of Carboxylic Acids, RCO₂H
21:31
Aciditiy of Carboxylic Acids, RCO₂H
21:32
Aciditiy of Carboxylic Acids, RCO₂H
24:48
Example: Which is the Stronger Acid?
24:49
Aciditiy of Carboxylic Acids, RCO₂H
30:06
Inductive Effects Decrease with Distance
30:07
Preparation of Carboxylic Acids, RCO₂H
31:55
A) By Oxidation
31:56
Preparation of Carboxylic Acids, RCO₂H
34:37
Oxidation of Alkenes/Alkynes - Ozonolysis
34:38
Preparation of Carboxylic Acids, RCO₂H
36:17
B) Preparation of RCO₂H from Organometallic Reagents
36:18
Preparation of Carboxylic Acids, RCO₂H
38:02
Example: Preparation of Carboxylic Acids
38:03
Preparation of Carboxylic Acids, RCO₂H
40:38
C) Preparation of RCO₂H by Hydrolysis of Carboxylic Acid Derivatives
40:39
Hydrolysis Mechanism
42:19
Hydrolysis Mechanism
42:20
Mechanism: Acyl Substitution (Addition/Elimination)
43:05
Hydrolysis Mechanism
47:27
Substitution Reaction
47:28
RO is Bad LG for SN1/SN2
47:39
RO is okay LG for Collapse of CTI
48:31
Hydrolysis Mechanism
50:07
Base-promoted Ester Hydrolysis (Saponification)
50:08
Applications of Carboxylic Acid Derivatives:
53:10
Saponification Reaction
53:11
Ester Hydrolysis
57:15
Acid-Catalyzed Mechanism
57:16
Ester Hydrolysis Requires Acide or Base
1:03:06
Ester Hydrolysis Requires Acide or Base
1:03:07
Nitrile Hydrolysis
1:05:22
Nitrile Hydrolysis
1:05:23
Nitrile Hydrolysis Mechanism
1:06:53
Nitrile Hydrolysis Mechanism
1:06:54
Use of Nitriles in Synthesis
1:12:39
Example: Nitirles in Synthesis
1:12:40
Carboxylic Acid Derivatives

1h 21m 4s

Intro
0:00
Carboxylic Acid Derivatives
0:05
Carboxylic Acid Derivatives
0:06
General Structure
1:00
Preparation of Carboxylic Acid Derivatives
1:19
Which Carbonyl is the Better E+?
1:20
Inductive Effects
1:54
Resonance
3:23
Preparation of Carboxylic Acid Derivatives
6:52
Which is Better E+, Ester or Acid Chloride?
6:53
Inductive Effects
7:02
Resonance
7:20
Preparation of Carboxylic Acid Derivatives
10:45
Which is Better E+, Carboxylic Acid or Anhydride?
10:46
Inductive Effects & Resonance
11:00
Overall: Order of Electrophilicity and Leaving Group
14:49
Order of Electrophilicity and Leaving Group
14:50
Example: Acid Chloride
16:26
Example: Carboxylate
19:17
Carboxylic Acid Derivative Interconversion
20:53
Carboxylic Acid Derivative Interconversion
20:54
Preparation of Acid Halides
24:31
Preparation of Acid Halides
24:32
Preparation of Anhydrides
25:45
A) Dehydration of Acids (For Symmetrical Anhydride)
25:46
Preparation of Anhydrides
27:29
Example: Dehydration of Acids
27:30
Preparation of Anhydrides
29:16
B) From an Acid Chloride (To Make Mixed Anhydride)
29:17
Mechanism
30:03
Preparation of Esters
31:53
A) From Acid Chloride or Anhydride
31:54
Preparation of Esters
33:48
B) From Carboxylic Acids (Fischer Esterification)
33:49
Mechanism
36:55
Preparations of Esters
41:38
Example: Predict the Product
41:39
Preparation of Esters
43:17
C) Transesterification
43:18
Mechanism
45:17
Preparation of Esters
47:58
D) SN2 with Carboxylate
47:59
Mechanism: Diazomethane
49:28
Preparation of Esters
51:01
Example: Transform
51:02
Preparation of Amides
52:27
A) From an Acid Cl or Anhydride
52:28
Preparations of Amides
54:47
B) Partial Hydrolysis of Nitriles
54:48
Preparation of Amides
56:11
Preparation of Amides: Find Alternate Path
56:12
Preparation of Amides
59:04
C) Can't be Easily Prepared from RCO₂H Directly
59:05
Reactions of Carboxylic Acid Derivatives with Nucleophiles
1:01:41
A) Hydride Nu: Review
1:01:42
A) Hydride Nu: Sodium Borohydride + Ester
1:02:43
Reactions of Carboxylic Acid Derivatives with Nucleophiles
1:03:57
Lithium Aluminum Hydride (LAH)
1:03:58
Mechanism
1:04:29
Summary of Hydride Reductions
1:07:09
Summary of Hydride Reductions 1
1:07:10
Summary of Hydride Reductions 2
1:07:36
Hydride Reduction of Amides
1:08:12
Hydride Reduction of Amides Mechanism
1:08:13
Reaction of Carboxylic Acid Derivatives with Organometallics
1:12:04
Review 1
1:12:05
Review 2
1:12:50
Reaction of Carboxylic Acid Derivatives with Organometallics
1:14:22
Example: Lactone
1:14:23
Special Hydride Nu: Reagents
1:16:34
Diisobutylaluminum Hydride
1:16:35
Example
1:17:25
Other Special Hydride
1:18:41
Addition of Organocuprates to Acid Chlorides
1:19:07
Addition of Organocuprates to Acid Chlorides
1:19:08
Section 8: Enols & Enolates
Enols and Enolates, Part 1

1h 26m 22s

Intro
0:00
Enols and Enolates
0:09
The Carbonyl
0:10
Keto-Enol Tautomerization
1:17
Keto-Enol Tautomerization Mechanism
2:28
Tautomerization Mechanism (2 Steps)
2:29
Keto-Enol Tautomerization Mechanism
5:15
Reverse Reaction
5:16
Mechanism
6:07
Formation of Enolates
7:27
Why is a Ketone's α H's Acidic?
7:28
Formation of Other Carbanions
10:05
Alkyne
10:06
Alkane and Alkene
10:53
Formation of an Enolate: Choice of Base
11:27
Example: Choice of Base
11:28
Formation of an Enolate: Choice of Base
13:56
Deprotonate, Stronger Base, and Lithium Diisopropyl Amide (LDA)
13:57
Formation of an Enolate: Choice of Base
15:48
Weaker Base & 'Active' Methylenes
15:49
Why Use NaOEt instead of NaOH?
19:01
Other Acidic 'α' Protons
20:30
Other Acidic 'α' Protons
20:31
Why is an Ester Less Acidic than a Ketone?
24:10
Other Acidic 'α' Protons
25:19
Other Acidic 'α' Protons Continue
25:20
How are Enolates Used
25:54
Enolates
25:55
Possible Electrophiles
26:21
Alkylation of Enolates
27:56
Alkylation of Enolates
27:57
Resonance Form
30:03
α-Halogenation
32:17
α-Halogenation
32:18
Iodoform Test for Methyl Ketones
33:47
α-Halogenation
35:55
Acid-Catalyzed
35:57
Mechanism: 1st Make Enol (2 Steps)
36:14
Whate Other Eloctrophiles ?
39:17
Aldol Condensation
39:38
Aldol Condensation
39:39
Aldol Mechanism
41:26
Aldol Mechanism: In Base, Deprotonate First
41:27
Aldol Mechanism
45:28
Mechanism for Loss of H₂O
45:29
Collapse of CTI and β-elimination Mechanism
47:51
Loss of H₂0 is not E2!
48:39
Aldol Summary
49:53
Aldol Summary
49:54
Base-Catalyzed Mechanism
52:34
Acid-Catalyzed Mechansim
53:01
Acid-Catalyzed Aldol Mechanism
54:01
First Step: Make Enol
54:02
Acid-Catalyzed Aldol Mechanism
56:54
Loss of H₂0 (β elimination)
56:55
Crossed/Mixed Aldol
1:00:55
Crossed/Mixed Aldol & Compound with α H's
1:00:56
Ketone vs. Aldehyde
1:02:30
Crossed/Mixed Aldol & Compound with α H's Continue
1:03:10
Crossed/Mixed Aldol
1:05:21
Mixed Aldol: control Using LDA
1:05:22
Crossed/Mixed Aldol Retrosynthesis
1:08:53
Example: Predic Aldol Starting Material (Aldol Retrosyntheiss)
1:08:54
Claisen Condensation
1:12:54
Claisen Condensation (Aldol on Esters)
1:12:55
Claisen Condensation
1:19:52
Example 1: Claisen Condensation
1:19:53
Claisen Condensation
1:22:48
Example 2: Claisen Condensation
1:22:49
Enols and Enolates, Part 2

50m 57s

Intro
0:00
Conjugate Additions
0:06
α, β-unsaturated Carbonyls
0:07
Conjugate Additions
1:50
'1,2-addition'
1:51
'1,-4-addition' or 'Conjugate Addition'
2:24
Conjugate Additions
4:53
Why can a Nu: Add to this Alkene?
4:54
Typical Alkene
5:09
α, β-unsaturated Alkene
5:39
Electrophilic Alkenes: Michael Acceptors
6:35
Other 'Electrophilic' Alkenes (Called 'Michael Acceptors)
6:36
1,4-Addition of Cuprates (R2CuLi)
8:29
1,4-Addition of Cuprates (R2CuLi)
8:30
1,4-Addition of Cuprates (R2CuLi)
11:23
Use Cuprates in Synthesis
11:24
Preparation of Cuprates
12:25
Prepare Organocuprate From Organolithium
12:26
Cuprates Also Do SN2 with RX E+ (Not True for RMgX, RLi)
13:06
1,4-Addition of Enolates: Michael Reaction
13:50
1,4-Addition of Enolates: Michael Reaction
13:51
Mechanism
15:57
1,4-Addition of Enolates: Michael Reaction
18:47
Example: 1,4-Addition of Enolates
18:48
1,4-Addition of Enolates: Michael Reaction
21:02
Michael Reaction, Followed by Intramolecular Aldol
21:03
Mechanism of the Robinson Annulation
24:26
Mechanism of the Robinson Annulation
24:27
Enols and Enolates: Advanced Synthesis Topics
31:10
Stablized Enolates and the Decarboxylation Reaction
31:11
Mechanism: A Pericyclic Reaction
32:08
Enols and Enolates: Advanced Synthesis Topics
33:32
Example: Advance Synthesis
33:33
Enols and Enolates: Advanced Synthesis Topics
36:10
Common Reagents: Diethyl Malonate
36:11
Common Reagents: Ethyl Acetoacetate
37:27
Enols and Enolates: Advanced Synthesis Topics
38:06
Example: Transform
38:07
Advanced Synthesis Topics: Enamines
41:52
Enamines
41:53
Advanced Synthesis Topics: Enamines
43:06
Reaction with Ketone/Aldehyde
43:07
Example
44:08
Advanced Synthesis Topics: Enamines
45:31
Example: Use Enamines as Nu: (Like Enolate)
45:32
Advanced Synthesis Topics: Enamines
47:56
Example
47:58
Section 9: Aromatic Compounds
Aromatic Compounds: Structure

1h 59s

Intro
0:00
Aromatic Compounds
0:05
Benzene
0:06
3D Sketch
1:33
Features of Benzene
4:41
Features of Benzene
4:42
Aromatic Stability
6:41
Resonance Stabilization of Benzene
6:42
Cyclohexatriene
7:24
Benzene (Actual, Experimental)
8:11
Aromatic Stability
9:03
Energy Graph
9:04
Aromaticity Requirements
9:55
1) Cyclic and Planar
9:56
2) Contiguous p Orbitals
10:49
3) Satisfy Huckel's Rule
11:20
Example: Benzene
12:32
Common Aromatic Compounds
13:28
Example: Pyridine
13:29
Common Aromatic Compounds
16:25
Example: Furan
16:26
Common Aromatic Compounds
19:42
Example: Thiophene
19:43
Example: Pyrrole
20:18
Common Aromatic Compounds
21:09
Cyclopentadienyl Anion
21:10
Cycloheptatrienyl Cation
23:48
Naphthalene
26:04
Determining Aromaticity
27:28
Example: Which of the Following are Aromatic?
27:29
Molecular Orbital (MO) Theory
32:26
What's So Special About '4n + 2' Electrons?
32:27
π bond & Overlapping p Orbitals
32:53
Molecular Orbital (MO) Diagrams
36:56
MO Diagram: Benzene
36:58
Drawing MO Diagrams
44:26
Example: 3-Membered Ring
44:27
Example: 4-Membered Ring
46:04
Drawing MO Diagrams
47:51
Example: 5-Membered Ring
47:52
Example: 8-Membered Ring
49:32
Aromaticity and Reactivity
51:03
Example: Which is More Acidic?
51:04
Aromaticity and Reactivity
56:03
Example: Which has More Basic Nitrogen, Pyrrole or Pyridine?
56:04
Aromatic Compounds: Reactions, Part 1

1h 24m 4s

Intro
0:00
Reactions of Benzene
0:07
N/R as Alkenes
0:08
Substitution Reactions
0:50
Electrophilic Aromatic Substitution
1:24
Electrophilic Aromatic Substitution
1:25
Mechanism Step 1: Addition of Electrophile
2:08
Mechanism Step 2: Loss of H+
4:14
Electrophilic Aromatic Substitution on Substituted Benzenes
5:21
Electron Donating Group
5:22
Electron Withdrawing Group
8:02
Halogen
9:23
Effects of Electron-Donating Groups (EDG)
10:23
Effects of Electron-Donating Groups (EDG)
10:24
What Effect Does EDG (OH) Have?
11:40
Reactivity
13:03
Regioselectivity
14:07
Regioselectivity: EDG is o/p Director
14:57
Prove It! Add E+ and Look at Possible Intermediates
14:58
Is OH Good or Bad?
17:38
Effects of Electron-Withdrawing Groups (EWG)
20:20
What Effect Does EWG Have?
20:21
Reactivity
21:28
Regioselectivity
22:24
Regioselectivity: EWG is a Meta Director
23:23
Prove It! Add E+ and Look at Competing Intermediates
23:24
Carbocation: Good or Bad?
26:01
Effects of Halogens on EAS
28:33
Inductive Withdrawal of e- Density vs. Resonance Donation
28:34
Summary of Substituent Effects on EAS
32:33
Electron Donating Group
32:34
Electron Withdrawing Group
33:37
Directing Power of Substituents
34:35
Directing Power of Substituents
34:36
Example
36:41
Electrophiles for Electrophilic Aromatic Substitution
38:43
Reaction: Halogenation
38:44
Electrophiles for Electrophilic Aromatic Substitution
40:27
Reaction: Nitration
40:28
Electrophiles for Electrophilic Aromatic Substitution
41:45
Reaction: Sulfonation
41:46
Electrophiles for Electrophilic Aromatic Substitution
43:19
Reaction: Friedel-Crafts Alkylation
43:20
Electrophiles for Electrophilic Aromatic Substitution
45:43
Reaction: Friedel-Crafts Acylation
45:44
Electrophilic Aromatic Substitution: Nitration
46:52
Electrophilic Aromatic Substitution: Nitration
46:53
Mechanism
48:56
Nitration of Aniline
52:40
Nitration of Aniline Part 1
52:41
Nitration of Aniline Part 2: Why?
54:12
Nitration of Aniline
56:10
Workaround: Protect Amino Group as an Amide
56:11
Electrophilic Aromatic Substitution: Sulfonation
58:16
Electrophilic Aromatic Substitution: Sulfonation
58:17
Example: Transform
59:25
Electrophilic Aromatic Substitution: Friedel-Crafts Alkylation
1:02:24
Electrophilic Aromatic Substitution: Friedel-Crafts Alkylation
1:02:25
Example & Mechanism
1:03:37
Friedel-Crafts Alkylation Drawbacks
1:05:48
A) Can Over-React (Dialkylation)
1:05:49
Friedel-Crafts Alkylation Drawbacks
1:08:21
B) Carbocation Can Rearrange
1:08:22
Mechanism
1:09:33
Friedel-Crafts Alkylation Drawbacks
1:13:35
Want n-Propyl? Use Friedel-Crafts Acylation
1:13:36
Reducing Agents
1:16:45
Synthesis with Electrophilic Aromatic Substitution
1:18:45
Example: Transform
1:18:46
Synthesis with Electrophilic Aromatic Substitution
1:20:59
Example: Transform
1:21:00
Aromatic Compounds: Reactions, Part 2

59m 10s

Intro
0:00
Reagents for Electrophilic Aromatic Substitution
0:07
Reagents for Electrophilic Aromatic Substitution
0:08
Preparation of Diazonium Salt
2:12
Preparation of Diazonium Salt
2:13
Reagents for Sandmeyer Reactions
4:14
Reagents for Sandmeyer Reactions
4:15
Apply Diazonium Salt in Synthesis
6:20
Example: Transform
6:21
Apply Diazonium Salt in Synthesis
9:14
Example: Synthesize Following Target Molecule from Benzene or Toluene
9:15
Apply Diazonium Salt in Synthesis
14:56
Example: Transform
14:57
Reactions of Aromatic Substituents
21:56
A) Reduction Reactions
21:57
Reactions of Aromatic Substituents
23:24
B) Oxidations of Arenes
23:25
Benzylic [ox] Even Breaks C-C Bonds!
25:05
Benzylic Carbon Can't Be Quaternary
25:55
Reactions of Aromatic Substituents
26:21
Example
26:22
Review of Benzoic Acid Synthesis
27:34
Via Hydrolysis
27:35
Via Grignard
28:20
Reactions of Aromatic Substituents
29:15
C) Benzylic Halogenation
29:16
Radical Stabilities
31:55
N-bromosuccinimide (NBS)
32:23
Reactions of Aromatic Substituents
33:08
D) Benzylic Substitutions
33:09
Reactions of Aromatic Side Chains
37:08
Example: Transform
37:09
Nucleophilic Aromatic Substitution
43:13
Nucleophilic Aromatic Substitution
43:14
Nucleophilic Aromatic Substitution
47:08
Example
47:09
Mechanism
48:00
Nucleophilic Aromatic Substitution
50:43
Example
50:44
Nucleophilic Substitution: Benzyne Mechanism
52:46
Nucleophilic Substitution: Benzyne Mechanism
52:47
Nucleophilic Substitution: Benzyne Mechanism
57:31
Example: Predict Product
57:32
Section 10: Dienes & Amines
Conjugated Dienes

1h 9m 12s

Intro
0:00
Conjugated Dienes
0:08
Conjugated π Bonds
0:09
Diene Stability
2:00
Diene Stability: Cumulated
2:01
Diene Stability: Isolated
2:37
Diene Stability: Conjugated
2:51
Heat of Hydrogenation
3:00
Allylic Carbocations and Radicals
5:15
Allylic Carbocations and Radicals
5:16
Electrophilic Additions to Dienes
7:00
Alkenes
7:01
Unsaturated Ketone
7:47
Electrophilic Additions to Dienes
8:28
Conjugated Dienes
8:29
Electrophilic Additions to Dienes
9:46
Mechanism (2-Steps): Alkene
9:47
Electrophilic Additions to Dienes
11:40
Mechanism (2-Steps): Diene
11:41
1,2 'Kinetic' Product
13:08
1,4 'Thermodynamic' Product
14:47
E vs. POR Diagram
15:50
E vs. POR Diagram
15:51
Kinetic vs. Thermodynamic Control
21:56
Kinetic vs. Thermodynamic Control
21:57
How? Reaction is Reversible!
23:51
1,2 (Less Stable product)
23:52
1,4 (More Stable Product)
25:16
Diels Alder Reaction
26:34
Diels Alder Reaction
26:35
Dienophiles (E+)
29:23
Dienophiles (E+)
29:24
Alkyne Diels-Alder Example
30:48
Example: Alkyne Diels-Alder
30:49
Diels-Alder Reaction: Dienes (Nu:)
32:22
Diels-Alder ReactionL Dienes (Nu:)
32:23
Diels-Alder Reaction: Dienes
33:51
Dienes Must Have 's-cis' Conformation
33:52
Example
35:25
Diels-Alder Reaction with Cyclic Dienes
36:08
Cyclic Dienes are Great for Diels-Alder Reaction
36:09
Cyclopentadiene
37:10
Diels-Alder Reaction: Bicyclic Products
40:50
Endo vs. Exo Terminology: Norbornane & Bicyclo Heptane
40:51
Example: Bicyclo Heptane
42:29
Diels-Alder Reaction with Cyclic Dienes
44:15
Example
44:16
Stereochemistry of the Diels-Alder Reaction
47:39
Stereochemistry of the Diels-Alder Reaction
47:40
Example
48:08
Stereochemistry of the Diels-Alder Reaction
50:21
Example
50:22
Regiochemistry of the Diels-Alder Reaction
52:42
Rule: 1,2-Product Preferred Over 1,3-Product
52:43
Regiochemistry of the Diels-Alder Reaction
54:18
Rule: 1,4-Product Preferred Over 1,3-Product
54:19
Regiochemistry of the Diels-Alder Reaction
55:02
Why 1,2-Product or 1,4-Product Favored?
55:03
Example
56:11
Diels-Alder Reaction
58:06
Example: Predict
58:07
Diels-Alder Reaction
1:01:27
Explain Why No Diels-Alder Reaction Takes Place in This Case
1:01:28
Diels-Alder Reaction
1:03:09
Example: Predict
1:03:10
Diels-Alder Reaction: Synthesis Problem
1:05:39
Diels-Alder Reaction: Synthesis Problem
1:05:40
Pericyclic Reactions and Molecular Orbital (MO) Theory

1h 21m 31s

Intro
0:00
Pericyclic Reactions
0:05
Pericyclic Reactions
0:06
Electrocyclic Reactions
1:19
Electrocyclic Reactions
1:20
Electrocyclic Reactions
3:13
Stereoselectivity
3:14
Electrocyclic Reactions
8:10
Example: Predict
8:11
Sigmatropic Rearrangements
12:29
Sigmatropic Rearrangements
12:30
Cope Rearrangement
14:44
Sigmatropic Rearrangements
16:44
Claisen Rearrangement 1
16:45
Claisen Rearrangement 2
17:46
Cycloaddition Reactions
19:22
Diels-Alder
19:23
1,3-Dipolar Cycloaddition
20:32
Cycloaddition Reactions: Stereochemistry
21:58
Cycloaddition Reactions: Stereochemistry
21:59
Cycloaddition Reactions: Heat or Light?
26:00
4+2 Cycloadditions
26:01
2+2 Cycloadditions
27:23
Molecular Orbital (MO) Theory of Chemical Reactions
29:26
Example 1: Molecular Orbital Theory of Bonding
29:27
Molecular Orbital (MO) Theory of Chemical Reactions
31:59
Example 2: Molecular Orbital Theory of Bonding
32:00
Molecular Orbital (MO) Theory of Chemical Reactions
33:33
MO Theory of Aromaticity, Huckel's Rule
33:34
Molecular Orbital (MO) Theory of Chemical Reactions
36:43
Review: Molecular Orbital Theory of Conjugated Systems
36:44
Molecular Orbital (MO) Theory of Chemical Reactions
44:56
Review: Molecular Orbital Theory of Conjugated Systems
44:57
Molecular Orbital (MO) Theory of Chemical Reactions
46:54
Review: Molecular Orbital Theory of Conjugated Systems
46:55
Molecular Orbital (MO) Theory of Chemical Reactions
48:36
Frontier Molecular Orbitals are Involved in Reactions
48:37
Examples
50:20
MO Theory of Pericyclic Reactions: The Woodward-Hoffmann Rules
51:51
Heat-promoted Pericyclic Reactions and Light-promoted Pericyclic Reactions
51:52
MO Theory of Pericyclic Reactions: The Woodward-Hoffmann Rules
53:42
Why is a [4+2] Cycloaddition Thermally Allowed While the [2+2] is Not?
53:43
MO Theory of Pericyclic Reactions: The Woodward-Hoffmann Rules
56:51
Why is a [2+2] Cycloaddition Photochemically Allowed?
56:52
Pericyclic Reaction Example I
59:16
Pericyclic Reaction Example I
59:17
Pericyclic Reaction Example II
1:07:40
Pericyclic Reaction Example II
1:07:41
Pericyclic Reaction Example III: Vitamin D - The Sunshine Vitamin
1:14:22
Pericyclic Reaction Example III: Vitamin D - The Sunshine Vitamin
1:14:23
Amines

34m 58s

Intro
0:00
Amines: Properties and Reactivity
0:04
Compare Amines to Alcohols
0:05
Amines: Lower Boiling Point than ROH
0:55
1) RNH₂ Has Lower Boiling Point than ROH
0:56
Amines: Better Nu: Than ROH
2:22
2) RNH₂ is a Better Nucleophile than ROH Example 1
2:23
RNH₂ is a Better Nucleophile than ROH Example 2
3:08
Amines: Better Nu: than ROH
3:47
Example
3:48
Amines are Good Bases
5:41
3) RNH₂ is a Good Base
5:42
Amines are Good Bases
7:06
Example 1
7:07
Example 2: Amino Acid
8:27
Alkyl vs. Aryl Amines
9:56
Example: Which is Strongest Base?
9:57
Alkyl vs. Aryl Amines
14:55
Verify by Comparing Conjugate Acids
14:56
Reaction of Amines
17:42
Reaction with Ketone/Aldehyde: 1° Amine (RNH₂)
17:43
Reaction of Amines
18:48
Reaction with Ketone/Aldehyde: 2° Amine (R2NH)
18:49
Use of Enamine: Synthetic Equivalent of Enolate
20:08
Use of Enamine: Synthetic Equivalent of Enolate
20:09
Reaction of Amines
24:10
Hofmann Elimination
24:11
Hofmann Elimination
26:16
Kinetic Product
26:17
Structure Analysis Using Hofmann Elimination
28:22
Structure Analysis Using Hofmann Elimination
28:23
Biological Activity of Amines
30:30
Adrenaline
31:07
Mescaline (Peyote Alkaloid)
31:22
Amino Acids, Amide, and Protein
32:14
Biological Activity of Amines
32:50
Morphine (Opium Alkaloid)
32:51
Epibatidine (Poison Dart Frog)
33:28
Nicotine
33:48
Choline (Nerve Impulse)
34:03
Section 11: Biomolecules & Polymers
Biomolecules

1h 53m 20s

Intro
0:00
Carbohydrates
1:11
D-glucose Overview
1:12
D-glucose: Cyclic Form (6-membered ring)
4:31
Cyclic Forms of Glucose: 6-membered Ring
8:24
α-D-glucopyranose & β-D-glucopyranose
8:25
Formation of a 5-Membered Ring
11:05
D-glucose: Formation of a 5-Membered Ring
11:06
Cyclic Forms of Glucose: 5-membered Ring
12:37
α-D-glucofuranose & β-D-glucofuranose
12:38
Carbohydrate Mechanism
14:03
Carbohydrate Mechanism
14:04
Reactions of Glucose: Acetal Formation
21:35
Acetal Formation: Methyl-α-D-glucoside
21:36
Hemiacetal to Acetal: Overview
24:58
Mechanism for Formation of Glycosidic Bond
25:51
Hemiacetal to Acetal: Mechanism
25:52
Formation of Disaccharides
29:34
Formation of Disaccharides
29:35
Some Polysaccharides: Starch
31:33
Amylose & Amylopectin
31:34
Starch: α-1,4-glycosidic Bonds
32:22
Properties of Starch Molecule
33:21
Some Polysaccharides: Cellulose
33:59
Cellulose: β-1,4-glycosidic bonds
34:00
Properties of Cellulose
34:59
Other Sugar-Containing Biomolecules
35:50
Ribonucleoside (RNA)
35:51
Deoxyribonucleoside (DMA)
36:59
Amino Acids & Proteins
37:32
α-amino Acids: Structure & Stereochemistry
37:33
Making a Protein (Condensation)
42:46
Making a Protein (Condensation)
42:47
Peptide Bond is Planar (Amide Resonance)
44:55
Peptide Bond is Planar (Amide Resonance)
44:56
Protein Functions
47:49
Muscle, Skin, Bones, Hair Nails
47:50
Enzymes
49:10
Antibodies
49:44
Hormones, Hemoglobin
49:58
Gene Regulation
50:20
Various Amino Acid Side Chains
50:51
Nonpolar
50:52
Polar
51:15
Acidic
51:24
Basic
51:55
Amino Acid Table
52:22
Amino Acid Table
52:23
Isoelectric Point (pI)
53:43
Isoelectric Point (pI) of Glycine
53:44
Isoelectric Point (pI) of Glycine: pH 11
56:42
Isoelectric Point (pI) of Glycine: pH 1
57:20
Isoelectric Point (pI), cont.
58:05
Asparatic Acid
58:06
Histidine
1:00:28
Isoelectric Point (pI), cont.
1:02:54
Example: What is the Net Charge of This Tetrapeptide at pH 6.0?
1:02:55
Nucleic Acids: Ribonucleosides
1:10:32
Nucleic Acids: Ribonucleosides
1:10:33
Nucleic Acids: Ribonucleotides
1:11:48
Ribonucleotides: 5' Phosphorylated Ribonucleosides
1:11:49
Ribonucleic Acid (RNA) Structure
1:12:35
Ribonucleic Acid (RNA) Structure
1:12:36
Nucleic Acids: Deoxyribonucleosides
1:14:08
Nucleic Acids: Deoxyribonucleosides
1:14:09
Deoxythymidine (T)
1:14:36
Nucleic Acids: Base-Pairing
1:15:17
Nucleic Acids: Base-Pairing
1:15:18
Double-Stranded Structure of DNA
1:18:16
Double-Stranded Structure of DNA
1:18:17
Model of DNA
1:19:40
Model of DNA
1:19:41
Space-Filling Model of DNA
1:20:46
Space-Filling Model of DNA
1:20:47
Function of RNA and DNA
1:23:06
DNA & Transcription
1:23:07
RNA & Translation
1:24:22
Genetic Code
1:25:09
Genetic Code
1:25:10
Lipids/Fats/Triglycerides
1:27:10
Structure of Glycerol
1:27:43
Saturated & Unsaturated Fatty Acids
1:27:51
Triglyceride
1:28:43
Unsaturated Fats: Lower Melting Points (Liquids/Oils)
1:29:15
Saturated Fat
1:29:16
Unsaturated Fat
1:30:10
Partial Hydrogenation
1:32:05
Saponification of Fats
1:35:11
Saponification of Fats
1:35:12
History of Soap
1:36:50
Carboxylate Salts form Micelles in Water
1:41:02
Carboxylate Salts form Micelles in Water
1:41:03
Cleaning Power of Micelles
1:42:21
Cleaning Power of Micelles
1:42:22
3-D Image of a Micelle
1:42:58
3-D Image of a Micelle
1:42:59
Synthesis of Biodiesel
1:44:04
Synthesis of Biodiesel
1:44:05
Phosphoglycerides
1:47:54
Phosphoglycerides
1:47:55
Cell Membranes Contain Lipid Bilayers
1:48:41
Cell Membranes Contain Lipid Bilayers
1:48:42
Bilayer Acts as Barrier to Movement In/Out of Cell
1:50:24
Bilayer Acts as Barrier to Movement In/Out of Cell
1:50:25
Organic Chemistry Meets Biology… Biochemistry!
1:51:12
Organic Chemistry Meets Biology… Biochemistry!
1:51:13
Polymers

45m 47s

Intro
0:00
Polymers
0:05
Monomer to Polymer: Vinyl Chloride to Polyvinyl Chloride
0:06
Polymer Properties
1:32
Polymer Properties
1:33
Natural Polymers: Rubber
2:30
Vulcanization
2:31
Natural Polymers: Polysaccharides
4:55
Example: Starch
4:56
Example: Cellulose
5:45
Natural Polymers: Proteins
6:07
Example: Keratin
6:08
DNA Strands
7:15
DNA Strands
7:16
Synthetic Polymers
8:30
Ethylene & Polyethylene: Lightweight Insulator & Airtight Plastic
8:31
Synthetic Organic Polymers
12:22
Polyethylene
12:28
Polyvinyl Chloride (PVC)
12:54
Polystyrene
13:28
Polyamide
14:34
Polymethyl Methacrylate
14:57
Kevlar
15:25
Synthetic Material Examples
16:30
How are Polymers Made?
21:00
Chain-growth Polymers Additions to Alkenes can be Radical, Cationic or Anionic
21:01
Chain Branching
22:34
Chain Branching
22:35
Special Reaction Conditions Prevent Branching
24:28
Ziegler-Natta Catalyst
24:29
Chain-Growth by Cationic Polymerization
27:35
Chain-Growth by Cationic Polymerization
27:36
Chain-Growth by Anionic Polymerization
29:35
Chain-Growth by Anionic Polymerization
29:36
Step-Growth Polymerization: Polyamides
32:16
Step-Growth Polymerization: Polyamides
32:17
Step-Growth Polymerization: Polyesters
34:23
Step-Growth Polymerization: Polyesters
34:24
Step-Growth Polymerization: Polycarbonates
35:56
Step-Growth Polymerization: Polycarbonates
35:57
Step-Growth Polymerization: Polyurethanes
37:18
Step-Growth Polymerization: Polyurethanes
37:19
Modifying Polymer Properties
39:35
Glass Transition Temperature
40:04
Crosslinking
40:42
Copolymers
40:58
Additives: Stabilizers
42:08
Additives: Flame Retardants
43:03
Additives: Plasticizers
43:41
Additives: Colorants
44:54
Section 12: Organic Synthesis
Organic Synthesis Strategies

2h 20m 24s

Intro
0:00
Organic Synthesis Strategies
0:15
Goal
0:16
Strategy
0:29
Example of a RetroSynthesis
1:30
Finding Starting Materials for Target Molecule
1:31
Synthesis Using Starting Materials
4:56
Synthesis of Alcohols by Functional Group Interconversion (FGI)
6:00
Synthesis of Alcohols by Functional Group Interconversion Overview
6:01
Alcohols by Reduction
7:43
Ketone to Alcohols
7:45
Aldehyde to Alcohols
8:26
Carboxylic Acid Derivative to Alcohols
8:36
Alcohols by Hydration of Alkenes
9:28
Hydration of Alkenes Using H₃O⁺
9:29
Oxymercuration-Demercuration
10:35
Hydroboration Oxidation
11:02
Alcohols by Substitution
11:42
Primary Alkyl Halide to Alcohols Using NaOH
11:43
Secondary Alkyl Halide to Alcohols Using Sodium Acetate
13:07
Tertiary Alkyl Halide to Alcohols Using H₂O
15:08
Synthesis of Alcohols by Forming a New C-C Bond
15:47
Recall: Alcohol & RMgBr
15:48
Retrosynthesis
17:28
Other Alcohol Disconnections
19:46
19:47
Synthesis Using PhMGgBr: Example 2
23:05
Synthesis of Alkyl Halides
26:06
Synthesis of Alkyl Halides Overview
26:07
Synthesis of Alkyl Halides by Free Radical Halogenation
27:04
Synthesis of Alkyl Halides by Free Radical Halogenation
27:05
Synthesis of Alkyl Halides by Substitution
29:06
Alcohol to Alkyl Halides Using HBr or HCl
29:07
Alcohol to Alkyl Halides Using SOCl₂
30:57
Alcohol to Alkyl Halides Using PBr₃ and Using P, I₂
31:03
Synthesis of Alkyl Halides by Addition
32:02
Alkene to Alkyl Halides Using HBr
32:03
Alkene to Alkyl Halides Using HBr & ROOR (Peroxides)
32:35
Example: Synthesis of Alkyl Halide
34:18
Example: Synthesis of Alkyl Halide
34:19
Synthesis of Ethers
39:25
Synthesis of Ethers
39:26
Example: Synthesis of an Ether
41:12
Synthesize TBME (t-butyl methyl ether) from Alcohol Starting Materials
41:13
Synthesis of Amines
46:05
Synthesis of Amines
46:06
Gabriel Synthesis of Amines
47:57
Gabriel Synthesis of Amines
47:58
Amines by SN2 with Azide Nu:
49:50
Amines by SN2 with Azide Nu:
49:51
Amines by SN2 with Cyanide Nu:
50:31
Amines by SN2 with Cyanide Nu:
50:32
Amines by Reduction of Amides
51:30
Amines by Reduction of Amides
51:31
Reductive Amination of Ketones/Aldehydes
52:42
Reductive Amination of Ketones/Aldehydes
52:43
Example : Synthesis of an Amine
53:47
Example 1: Synthesis of an Amine
53:48
Example 2: Synthesis of an Amine
56:16
Synthesis of Alkenes
58:20
Synthesis of Alkenes Overview
58:21
Synthesis of Alkenes by Elimination
59:04
Synthesis of Alkenes by Elimination Using NaOH & Heat
59:05
Synthesis of Alkenes by Elimination Using H₂SO₄ & Heat
59:57
Synthesis of Alkenes by Reduction
1:02:05
Alkyne to Cis Alkene
1:02:06
Alkyne to Trans Alkene
1:02:56
Synthesis of Alkenes by Wittig Reaction
1:03:46
Synthesis of Alkenes by Wittig Reaction
1:03:47
Retrosynthesis of an Alkene
1:05:35
Example: Synthesis of an Alkene
1:06:57
Example: Synthesis of an Alkene
1:06:58
Making a Wittig Reagent
1:10:31
Synthesis of Alkynes
1:13:09
Synthesis of Alkynes
1:13:10
Synthesis of Alkynes by Elimination (FGI)
1:13:42
First Step: Bromination of Alkene
1:13:43
Second Step: KOH Heat
1:14:22
Synthesis of Alkynes by Alkylation
1:15:02
Synthesis of Alkynes by Alkylation
1:15:03
Retrosynthesis of an Alkyne
1:16:18
Example: Synthesis of an Alkyne
1:17:40
Example: Synthesis of an Alkyne
1:17:41
Synthesis of Alkanes
1:20:52
Synthesis of Alkanes
1:20:53
Synthesis of Aldehydes & Ketones
1:21:38
Oxidation of Alcohol Using PCC or Swern
1:21:39
Oxidation of Alkene Using 1) O₃, 2)Zn
1:22:42
Reduction of Acid Chloride & Nitrile Using DiBAL-H
1:23:25
Hydration of Alkynes
1:24:55
Synthesis of Ketones by Acyl Substitution
1:26:12
Reaction with R'₂CuLi
1:26:13
Reaction with R'MgBr
1:27:13
Synthesis of Aldehydes & Ketones by α-Alkylation
1:28:00
Synthesis of Aldehydes & Ketones by α-Alkylation
1:28:01
Retrosynthesis of a Ketone
1:30:10
Acetoacetate Ester Synthesis of Ketones
1:31:05
Acetoacetate Ester Synthesis of Ketones: Step 1
1:31:06
Acetoacetate Ester Synthesis of Ketones: Step 2
1:32:13
Acetoacetate Ester Synthesis of Ketones: Step 3
1:32:50
Example: Synthesis of a Ketone
1:34:11
Example: Synthesis of a Ketone
1:34:12
Synthesis of Carboxylic Acids
1:37:15
Synthesis of Carboxylic Acids
1:37:16
Example: Synthesis of a Carboxylic Acid
1:37:59
Example: Synthesis of a Carboxylic Acid (Option 1)
1:38:00
Example: Synthesis of a Carboxylic Acid (Option 2)
1:40:51
Malonic Ester Synthesis of Carboxylic Acid
1:42:34
Malonic Ester Synthesis of Carboxylic Acid: Step 1
1:42:35
Malonic Ester Synthesis of Carboxylic Acid: Step 2
1:43:36
Malonic Ester Synthesis of Carboxylic Acid: Step 3
1:44:01
Example: Synthesis of a Carboxylic Acid
1:44:53
Example: Synthesis of a Carboxylic Acid
1:44:54
Synthesis of Carboxylic Acid Derivatives
1:48:05
Synthesis of Carboxylic Acid Derivatives
1:48:06
Alternate Ester Synthesis
1:48:58
Using Fischer Esterification
1:48:59
Using SN2 Reaction
1:50:18
Using Diazomethane
1:50:56
Using 1) LDA, 2) R'-X
1:52:15
Practice: Synthesis of an Alkyl Chloride
1:53:11
Practice: Synthesis of an Alkyl Chloride
1:53:12
Patterns of Functional Groups in Target Molecules
1:59:53
Recall: Aldol Reaction
1:59:54
β-hydroxy Ketone Target Molecule
2:01:12
α,β-unsaturated Ketone Target Molecule
2:02:20
Patterns of Functional Groups in Target Molecules
2:03:15
Recall: Michael Reaction
2:03:16
Retrosynthesis: 1,5-dicarbonyl Target Molecule
2:04:07
Patterns of Functional Groups in Target Molecules
2:06:38
Recall: Claisen Condensation
2:06:39
Retrosynthesis: β-ketoester Target Molecule
2:07:30
2-Group Target Molecule Summary
2:09:03
2-Group Target Molecule Summary
2:09:04
Example: Synthesis of Epoxy Ketone
2:11:19
Synthesize the Following Target Molecule from Cyclohexanone: Part 1 - Retrosynthesis
2:11:20
Synthesize the Following Target Molecule from Cyclohexanone: Part 2 - Synthesis
2:14:10
Example: Synthesis of a Diketone
2:16:57
Synthesis of a Diketone: Step 1 - Retrosynthesis
2:16:58
Synthesis of a Diketone: Step 2 - Synthesis
2:18:51
Section 12: Organic Synthesis & Organic Analysis
Organic Analysis: Classical & Modern Methods

46m 46s

Intro
0:00
Organic Analysis: Classical Methods
0:17
Classical Methods for Identifying Chemicals
0:18
Organic Analysis: Classical Methods
2:21
When is Structure Identification Needed?
2:22
Organic Analysis: Classical Methods
6:17
Classical Methods of Structure Identification: Physical Appearance
6:18
Classical Methods of Structure Identification: Physical Constants
6:42
Organic Analysis: Classical Methods
7:37
Classical Methods of Structure Identification: Solubility Tests - Water
7:38
Organic Analysis: Classical Methods
10:51
Classical Methods of Structure Identification: Solubility Tests - 5% aq. HCl Basic FG (Amines)
10:52
Organic Analysis: Classical Methods
11:50
Classical Methods of Structure Identification: Solubility Tests - 5% aq. NaOH Acidic FG (Carboxylic Acids, Phenols)
11:51
Organic Analysis: Classical Methods
13:28
Classical Methods of Structure Identification: Solubility Tests - 5% aq. NaHCO3 Strongly Acidic FG (Carboxylic Acids)
13:29
Organic Analysis: Classical Methods
15:35
Classical Methods of Structure Identification: Solubility Tests - Insoluble in All of the Above
15:36
Organic Analysis: Classical Methods
16:49
Classical Methods of Structure Identification: Idoform Test for Methyl Ketones
16:50
Organic Analysis: Classical Methods
22:02
Classical Methods of Structure Identification: Tollens' Test or Fehling's Solution for Aldehydes
22:03
Organic Analysis: Classical Methods
25:01
Useful Application of Classical Methods: Glucose Oxidase on Glucose Test Strips
25:02
Organic Analysis: Classical Methods
26:26
Classical Methods of Structure Identification: Starch-iodide Test
26:27
Organic Analysis: Classical Methods
28:22
Classical Methods of Structure Identification: Lucas Reagent to Determine Primary/Secondary/Tertiary Alcohol
28:23
Organic Analysis: Classical Methods
31:35
Classical Methods of Structure Identification: Silver Nitrate Test for Alkyl Halides
31:36
Organic Analysis: Classical Methods
33:23
Preparation of Derivatives
33:24
Organic Analysis: Modern Methods
36:55
Modern Methods of Chemical Characterization
36:56
Organic Analysis: Modern Methods
40:36
Checklist for Manuscripts Submitted to the ACS Journal Organic Letters
40:37
Organic Analysis: Modern Methods
42:39
Checklist for Manuscripts Submitted to the ACS Journal Organic Letters
42:40
Analysis of Stereochemistry

1h 2m 52s

Intro
0:00
Chirality & Optical Activity
0:32
Levorotatory & Dextrorotatory
0:33
Example: Optically Active?
2:22
Example: Optically Active?
2:23
Measurement of Specific Rotation, [α]
5:09
Measurement of Specific Rotation, [α]
5:10
Example: Calculation of Specific Rotation
8:56
Example: Calculation of Specific Rotation
8:57
Variability of Specific Rotation, [α]
12:52
Variability of Specific Rotation, [α]
12:53
Other Measures of Optical Activity: ORD and CD
15:04
Optical Rotary Dispersion (ORD)
15:05
Circular Dischroism (CD)
18:32
Circular Dischroism (CD)
18:33
Mixtures of Enantiomers
20:16
Racemic Mixtures
20:17
Unequal Mixtures of Enantiomers
21:36
100% ee
22:48
0% ee
23:34
Example: Definition of ee?
24:00
Example: Definition of ee?
24:01
Analysis of Optical Purity: [α]
27:47
[α] Measurement Can Be Used for Known Compounds
27:48
Analysis of Optical Purity: [α]
34:30
NMR Methods Using a Chiral Derivatizing Agent (CDA): Mosher's Reagent
34:31
Analysis of Optical Purity: [α]
40:01
NMR Methods Using a Chiral Derivatizing Agent (CDA): CDA Salt Formation
40:02
Analysis of Optical Purity: Chromatography
42:46
Chiral Chromatography
42:47
Stereochemistry Analysis by NMR: J Values (Coupling Constant)
51:28
NMR Methods for Structure Determination
51:29
Stereochemistry Analysis by NRM: NOE
57:00
NOE - Nuclear Overhauser Effect ( 2D Versions: NOESY or ROESY)
57:01
Section 13: Spectroscopy
Infrared Spectroscopy, Part I

1h 4m

Intro
0:00
Infrared (IR) Spectroscopy
0:09
Introduction to Infrared (IR) Spectroscopy
0:10
Intensity of Absorption Is Proportional to Change in Dipole
3:08
IR Spectrum of an Alkane
6:08
Pentane
6:09
IR Spectrum of an Alkene
13:12
1-Pentene
13:13
IR Spectrum of an Alkyne
15:49
1-Pentyne
15:50
IR Spectrum of an Aromatic Compound
18:02
Methylbenzene
18:24
IR of Substituted Aromatic Compounds
24:04
IR of Substituted Aromatic Compounds
24:05
IR Spectrum of 1,2-Disubstituted Aromatic
25:30
1,2-dimethylbenzene
25:31
IR Spectrum of 1,3-Disubstituted Aromatic
27:15
1,3-dimethylbenzene
27:16
IR Spectrum of 1,4-Disubstituted Aromatic
28:41
1,4-dimethylbenzene
28:42
IR Spectrum of an Alcohol
29:34
1-pentanol
29:35
IR Spectrum of an Amine
32:39
1-butanamine
32:40
IR Spectrum of a 2° Amine
34:50
Diethylamine
34:51
IR Spectrum of a 3° Amine
35:47
Triethylamine
35:48
IR Spectrum of a Ketone
36:41
2-butanone
36:42
IR Spectrum of an Aldehyde
40:10
Pentanal
40:11
IR Spectrum of an Ester
42:38
Butyl Propanoate
42:39
IR Spectrum of a Carboxylic Acid
44:26
Butanoic Acid
44:27
Sample IR Correlation Chart
47:36
Sample IR Correlation Chart: Wavenumber and Functional Group
47:37
Predicting IR Spectra: Sample Structures
52:06
Example 1
52:07
Example 2
53:29
Example 3
54:40
Example 4
57:08
Example 5
58:31
Example 6
59:07
Example 7
1:00:52
Example 8
1:02:20
Infrared Spectroscopy, Part II

48m 34s

Intro
0:00
Interpretation of IR Spectra: a Basic Approach
0:05
Interpretation of IR Spectra: a Basic Approach
0:06
Other Peaks to Look for
3:39
Examples
5:17
Example 1
5:18
Example 2
9:09
Example 3
11:52
Example 4
14:03
Example 5
16:31
Example 6
19:31
Example 7
22:32
Example 8
24:39
IR Problems Part 1
28:11
IR Problem 1
28:12
IR Problem 2
31:14
IR Problem 3
32:59
IR Problem 4
34:23
IR Problem 5
35:49
IR Problem 6
38:20
IR Problems Part 2
42:36
IR Problem 7
42:37
IR Problem 8
44:02
IR Problem 9
45:07
IR Problems10
46:10
Nuclear Magnetic Resonance (NMR) Spectroscopy, Part I

1h 32m 14s

Intro
0:00
Purpose of NMR
0:14
Purpose of NMR
0:15
How NMR Works
2:17
How NMR Works
2:18
Information Obtained From a ¹H NMR Spectrum
5:51
No. of Signals, Integration, Chemical Shifts, and Splitting Patterns
5:52
Number of Signals in NMR (Chemical Equivalence)
7:52
Example 1: How Many Signals in ¹H NMR?
7:53
Example 2: How Many Signals in ¹H NMR?
9:36
Example 3: How Many Signals in ¹H NMR?
12:15
Example 4: How Many Signals in ¹H NMR?
13:47
Example 5: How Many Signals in ¹H NMR?
16:12
Size of Signals in NMR (Peak Area or Integration)
21:23
Size of Signals in NMR (Peak Area or Integration)
21:24
Using Integral Trails
25:15
Example 1: C₈H₁₈O
25:16
Example 2: C₃H₈O
27:17
Example 3: C₇H₈
28:21
Location of NMR Signal (Chemical Shift)
29:05
Location of NMR Signal (Chemical Shift)
29:06
¹H NMR Chemical Shifts
33:20
¹H NMR Chemical Shifts
33:21
¹H NMR Chemical Shifts (Protons on Carbon)
37:03
¹H NMR Chemical Shifts (Protons on Carbon)
37:04
Chemical Shifts of H's on N or O
39:01
Chemical Shifts of H's on N or O
39:02
Estimating Chemical Shifts
41:13
Example 1: Estimating Chemical Shifts
41:14
Example 2: Estimating Chemical Shifts
43:22
Functional Group Effects are Additive
45:28
Calculating Chemical Shifts
47:38
Methylene Calculation
47:39
Methine Calculation
48:20
Protons on sp³ Carbons: Chemical Shift Calculation Table
48:50
Example: Estimate the Chemical Shift of the Selected H
50:29
Effects of Resonance on Chemical Shifts
53:11
Example 1: Effects of Resonance on Chemical Shifts
53:12
Example 2: Effects of Resonance on Chemical Shifts
55:09
Example 3: Effects of Resonance on Chemical Shifts
57:08
Shape of NMR Signal (Splitting Patterns)
59:17
Shape of NMR Signal (Splitting Patterns)
59:18
Understanding Splitting Patterns: The 'n+1 Rule'
1:01:24
Understanding Splitting Patterns: The 'n+1 Rule'
1:01:25
Explanation of n+1 Rule
1:02:42
Explanation of n+1 Rule: One Neighbor
1:02:43
Explanation of n+1 Rule: Two Neighbors
1:06:23
Summary of Splitting Patterns
1:06:24
Summary of Splitting Patterns
1:10:45
Predicting ¹H NMR Spectra
1:10:46
Example 1: Predicting ¹H NMR Spectra
1:13:30
Example 2: Predicting ¹H NMR Spectra
1:19:07
Example 3: Predicting ¹H NMR Spectra
1:23:50
Example 4: Predicting ¹H NMR Spectra
1:29:27
Nuclear Magnetic Resonance (NMR) Spectroscopy, Part II

2h 3m 48s

Intro
0:00
¹H NMR Problem-Solving Strategies
0:18
Step 1: Analyze IR Spectrum (If Provided)
0:19
Step 2: Analyze Molecular Formula (If Provided)
2:06
Step 3: Draw Pieces of Molecule
3:49
Step 4: Confirm Pieces
6:30
Step 5: Put the Pieces Together!
7:23
Step 6: Check Your Answer!
8:21
Examples
9:17
Example 1: Determine the Structure of a C₉H₁₀O₂ Compound with the Following ¹H NMR Data
9:18
Example 2: Determine the Structure of a C₉H₁₀O₂ Compound with the Following ¹H NMR Data
17:27
¹H NMR Practice
20:57
¹H NMR Practice 1: C₁₀H₁₄
20:58
¹H NMR Practice 2: C₄H₈O₂
29:50
¹H NMR Practice 3: C₆H₁₂O₃
39:19
¹H NMR Practice 4: C₈H₁₈
50:19
More About Coupling Constants (J Values)
57:11
Vicinal (3-bond) and Geminal (2-bond)
57:12
Cyclohexane (ax-ax) and Cyclohexane (ax-eq) or (eq-eq)
59:50
Geminal (Alkene), Cis (Alkene), and Trans (Alkene)
1:02:40
Allylic (4-bond) and W-coupling (4-bond) (Rigid Structures Only)
1:04:05
¹H NMR Advanced Splitting Patterns
1:05:39
Example 1: ¹H NMR Advanced Splitting Patterns
1:05:40
Example 2: ¹H NMR Advanced Splitting Patterns
1:10:01
Example 3: ¹H NMR Advanced Splitting Patterns
1:13:45
¹H NMR Practice
1:22:53
¹H NMR Practice 5: C₁₁H₁₇N
1:22:54
¹H NMR Practice 6: C₉H₁₀O
1:34:04
¹³C NMR Spectroscopy
1:44:49
¹³C NMR Spectroscopy
1:44:50
¹³C NMR Chemical Shifts
1:47:24
¹³C NMR Chemical Shifts Part 1
1:47:25
¹³C NMR Chemical Shifts Part 2
1:48:59
¹³C NMR Practice
1:50:16
¹³C NMR Practice 1
1:50:17
¹³C NMR Practice 2
1:58:30
C-13 DEPT NMR Experiments

23m 10s

Intro
0:00
C-13 DEPT NMR Spectoscopy
0:13
Overview
0:14
C-13 DEPT NMR Spectoscopy, Cont.
3:31
Match C-13 Peaks to Carbons on Structure
3:32
C-13 DEPT NMR Spectoscopy, Cont.
8:46
Predict the DEPT-90 and DEPT-135 Spectra for the Given Compound
8:47
C-13 DEPT NMR Spectoscopy, Cont.
12:30
Predict the DEPT-90 and DEPT-135 Spectra for the Given Compound
12:31
C-13 DEPT NMR Spectoscopy, Cont.
17:19
Determine the Structure of an Unknown Compound using IR Spectrum and C-13 DEPT NMR
17:20
Two-Dimensional NMR Techniques: COSY

33m 39s

Intro
0:00
Two-Dimensional NMR Techniques: COSY
0:14
How Do We Determine Which Protons are Related in the NMR?
0:15
Two-Dimensional NMR Techniques: COSY
1:48
COSY Spectra
1:49
Two-Dimensional NMR Techniques: COSY
7:00
COSY Correlation
7:01
Two-Dimensional NMR Techniques: COSY
8:55
Complete the COSY NMR Spectrum for the Given Compoun
8:56
NMR Practice Problem
15:40
Provide a Structure for the Unknown Compound with the H NMR and COSY Spectra Shown
15:41
Two-Dimensional NMR Techniques: HETCOR & HMBC

15m 5s

Intro
0:00
HETCOR
0:15
Heteronuclear Correlation Spectroscopy
0:16
HETCOR
2:04
HETCOR Example
2:05
HMBC
11:07
Heteronuclear Multiple Bond Correlation
11:08
HMBC
13:14
HMB Example
13:15
Mass Spectrometry

1h 28m 35s

Intro
0:00
Introduction to Mass Spectrometry
0:37
Uses of Mass Spectrometry: Molecular Mass
0:38
Uses of Mass Spectrometry: Molecular Formula
1:04
Uses of Mass Spectrometry: Structural Information
1:21
Uses of Mass Spectrometry: In Conjunction with Gas Chromatography
2:03
Obtaining a Mass Spectrum
2:59
Obtaining a Mass Spectrum
3:00
The Components of a Mass Spectrum
6:44
The Components of a Mass Spectrum
6:45
What is the Mass of a Single Molecule
12:13
Example: CH₄
12:14
Example: ¹³CH₄
12:51
What Ratio is Expected for the Molecular Ion Peaks of C₂H₆?
14:20
Other Isotopes of High Abundance
16:30
Example: Cl Atoms
16:31
Example: Br Atoms
18:33
Mass Spectrometry of Chloroethane
19:22
Mass Spectrometry of Bromobutane
21:23
Isotopic Abundance can be Calculated
22:48
What Ratios are Expected for the Molecular Ion Peaks of CH₂Br₂?
22:49
Determining Molecular Formula from High-resolution Mass Spectrometry
26:53
Exact Masses of Various Elements
26:54
Fragmentation of various Functional Groups
28:42
What is More Stable, a Carbocation C⁺ or a Radical R?
28:43
Fragmentation is More Likely If It Gives Relatively Stable Carbocations and Radicals
31:37
Mass Spectra of Alkanes
33:15
Example: Hexane
33:16
Fragmentation Method 1
34:19
Fragmentation Method 2
35:46
Fragmentation Method 3
36:15
Mass of Common Fragments
37:07
Mass of Common Fragments
37:08
Mass Spectra of Alkanes
39:28
Mass Spectra of Alkanes
39:29
What are the Peaks at m/z 15 and 71 So Small?
41:01
Branched Alkanes
43:12
Explain Why the Base Peak of 2-methylhexane is at m/z 43 (M-57)
43:13
Mass Spectra of Alkenes
45:42
Mass Spectra of Alkenes: Remove 1 e⁻
45:43
Mass Spectra of Alkenes: Fragment
46:14
High-Energy Pi Electron is Most Likely Removed
47:59
Mass Spectra of Aromatic Compounds
49:01
Mass Spectra of Aromatic Compounds
49:02
Mass Spectra of Alcohols
51:32
Mass Spectra of Alcohols
51:33
Mass Spectra of Ethers
54:53
Mass Spectra of Ethers
54:54
Mass Spectra of Amines
56:49
Mass Spectra of Amines
56:50
Mass Spectra of Aldehydes & Ketones
59:23
Mass Spectra of Aldehydes & Ketones
59:24
McLafferty Rearrangement
1:01:29
McLafferty Rearrangement
1:01:30
Mass Spectra of Esters
1:04:15
Mass Spectra of Esters
1:01:16
Mass Spectrometry Discussion I
1:05:01
For the Given Molecule (M=58), Do You Expect the More Abundant Peak to Be m/z 15 or m/z 43?
1:05:02
Mass Spectrometry Discussion II
1:08:13
For the Given Molecule (M=74), Do You Expect the More Abundant Peak to Be m/z 31, m/z 45, or m/z 59?
1:08:14
Mass Spectrometry Discussion III
1:11:42
Explain Why the Mass Spectra of Methyl Ketones Typically have a Peak at m/z 43
1:11:43
Mass Spectrometry Discussion IV
1:14:46
In the Mass Spectrum of the Given Molecule (M=88), Account for the Peaks at m/z 45 and m/z 57
1:14:47
Mass Spectrometry Discussion V
1:18:25
How Could You Use Mass Spectrometry to Distinguish Between the Following Two Compounds (M=73)?
1:18:26
Mass Spectrometry Discussion VI
1:22:45
What Would be the m/z Ratio for the Fragment for the Fragment Resulting from a McLafferty Rearrangement for the Following Molecule (M=114)?
1:22:46
Section 14: Organic Chemistry Lab
Completing the Reagent Table for Prelab

21m 9s

Intro
0:00
Sample Reagent Table
0:11
Reagent Table Overview
0:12
Calculate Moles of 2-bromoaniline
6:44
Calculate Molar Amounts of Each Reagent
9:20
Calculate Mole of NaNO₂
9:21
Calculate Moles of KI
10:33
Identify the Limiting Reagent
11:17
Which Reagent is the Limiting Reagent?
11:18
Calculate Molar Equivalents
13:37
Molar Equivalents
13:38
Calculate Theoretical Yield
16:40
Theoretical Yield
16:41
Calculate Actual Yield (%Yield)
18:30
Actual Yield (%Yield)
18:31
Introduction to Melting Points

16m 10s

Intro
0:00
Definition of a Melting Point (mp)
0:04
Definition of a Melting Point (mp)
0:05
Solid Samples Melt Gradually
1:49
Recording Range of Melting Temperature
2:04
Melting Point Theory
3:14
Melting Point Theory
3:15
Effects of Impurities on a Melting Point
3:57
Effects of Impurities on a Melting Point
3:58
Special Exception: Eutectic Mixtures
5:09
Freezing Point Depression by Solutes
5:39
Melting Point Uses
6:19
Solid Compound
6:20
Determine Purity of a Sample
6:42
Identify an Unknown Solid
7:06
Recording a Melting Point
9:03
Pack 1-3 mm of Dry Powder in MP Tube
9:04
Slowly Heat Sample
9:55
Record Temperature at First Sign of Melting
10:33
Record Temperature When Last Crystal Disappears
11:26
Discard MP Tube in Glass Waste
11:32
Determine Approximate MP
11:42
Tips, Tricks and Warnings
12:28
Use Small, Tightly Packed Sample
12:29
Be Sure MP Apparatus is Cool
12:45
Never Reuse a MP Tube
13:16
Sample May Decompose
13:30
If Pure Melting Point (MP) Doesn't Match Literature
14:20
Melting Point Lab

8m 17s

Intro
0:00
Melting Point Tubes
0:40
Melting Point Apparatus
3:42
Recording a melting Point
5:50
Introduction to Recrystallization

22m

Intro
0:00
Crystallization to Purify a Solid
0:10
Crude Solid
0:11
Hot Solution
0:20
Crystals
1:09
Supernatant Liquid
1:20
Theory of Crystallization
2:34
Theory of Crystallization
2:35
Analysis and Obtaining a Second Crop
3:40
Crystals → Melting Point, TLC
3:41
Supernatant Liquid → Crude Solid → Pure Solid
4:18
Crystallize Again → Pure Solid (2nd Crop)
4:32
Choosing a Solvent
5:19
1. Product is Very Soluble at High Temperatures
5:20
2. Product has Low Solubility at Low Temperatures
6:00
3. Impurities are Soluble at All Temperatures
6:16
Check Handbooks for Suitable Solvents
7:33
Why Isn't This Dissolving?!
8:46
If Solid Remains When Solution is Hot
8:47
Still Not Dissolved in Hot Solvent?
10:18
Where Are My Crystals?!
12:23
If No Crystals Form When Solution is Cooled
12:24
Still No Crystals?
14:59
Tips, Tricks and Warnings
16:26
Always Use a Boiling Chip or Stick!
16:27
Use Charcoal to Remove Colored Impurities
16:52
Solvent Pairs May Be Used
18:23
Product May 'Oil Out'
20:11
Recrystallization Lab

19m 7s

Intro
0:00
Step 1: Dissolving the Solute in the Solvent
0:12
Hot Filtration
6:33
Step 2: Cooling the Solution
8:01
Step 3: Filtering the Crystals
12:08
Step 4: Removing & Drying the Crystals
16:10
Introduction to Distillation

25m 54s

Intro
0:00
Distillation: Purify a Liquid
0:04
Simple Distillation
0:05
Fractional Distillation
0:55
Theory of Distillation
1:04
Theory of Distillation
1:05
Vapor Pressure and Volatility
1:52
Vapor Pressure
1:53
Volatile Liquid
2:28
Less Volatile Liquid
3:09
Vapor Pressure vs. Boiling Point
4:03
Vapor Pressure vs. Boiling Point
4:04
Increasing Vapor Pressure
4:38
The Purpose of Boiling Chips
6:46
The Purpose of Boiling Chips
6:47
Homogeneous Mixtures of Liquids
9:24
Dalton's Law
9:25
Raoult's Law
10:27
Distilling a Mixture of Two Liquids
11:41
Distilling a Mixture of Two Liquids
11:42
Simple Distillation: Changing Vapor Composition
12:06
Vapor & Liquid
12:07
Simple Distillation: Changing Vapor Composition
14:47
Azeotrope
18:41
Fractional Distillation: Constant Vapor Composition
19:42
Fractional Distillation: Constant Vapor Composition
19:43
Distillation Lab

24m 13s

Intro
0:00
Glassware Overview
0:04
Heating a Sample
3:09
Bunsen Burner
3:10
Heating Mantle 1
4:45
Heating Mantle 2
6:18
Hot Plate
7:10
Simple Distillation Lab
8:37
Fractional Distillation Lab
17:13
Removing the Distillation Set-Up
22:41
Introduction to TLC (Thin-Layer Chromatography)

28m 51s

Intro
0:00
Chromatography
0:06
Purification & Analysis
0:07
Types of Chromatography: Thin-layer, Column, Gas, & High Performance Liquid
0:24
Theory of Chromatography
0:44
Theory of Chromatography
0:45
Performing a Thin-layer Chromatography (TLC) Analysis
2:30
Overview: Thin-layer Chromatography (TLC) Analysis
2:31
Step 1: 'Spot' the TLC Plate
4:11
Step 2: Prepare the Developing Chamber
5:54
Step 3: Develop the TLC Plate
7:30
Step 4: Visualize the Spots
9:02
Step 5: Calculate the Rf for Each Spot
12:00
Compound Polarity: Effect on Rf
16:50
Compound Polarity: Effect on Rf
16:51
Solvent Polarity: Effect on Rf
18:47
Solvent Polarity: Effect on Rf
18:48
Example: EtOAc & Hexane
19:35
Other Types of Chromatography
22:27
Thin-layer Chromatography (TLC)
22:28
Column Chromatography
22:56
High Performance Liquid (HPLC)
23:59
Gas Chromatography (GC)
24:38
Preparative 'prep' Scale Possible
28:05
TLC Analysis Lab

20m 50s

Intro
0:00
Step 1: 'Spot' the TLC Plate
0:06
Step 2: Prepare the Developing Chamber
4:06
Step 3: Develop the TLC Plate
6:26
Step 4: Visualize the Spots
7:45
Step 5: Calculate the Rf for Each Spot
11:48
How to Make Spotters
12:58
TLC Plate
16:04
Flash Column Chromatography
17:11
Introduction to Extractions

34m 25s

Intro
0:00
Extraction Purify, Separate Mixtures
0:07
Adding a Second Solvent
0:28
Mixing Two Layers
0:38
Layers Settle
0:54
Separate Layers
1:05
Extraction Uses
1:20
To Separate Based on Difference in Solubility/Polarity
1:21
To Separate Based on Differences in Reactivity
2:11
Separate & Isolate
2:20
Theory of Extraction
3:03
Aqueous & Organic Phases
3:04
Solubility: 'Like Dissolves Like'
3:25
Separation of Layers
4:06
Partitioning
4:14
Distribution Coefficient, K
5:03
Solutes Partition Between Phases
5:04
Distribution Coefficient, K at Equilibrium
6:27
Acid-Base Extractions
8:09
Organic Layer
8:10
Adding Aqueous HCl & Mixing Two Layers
8:46
Neutralize (Adding Aqueous NaOH)
10:05
Adding Organic Solvent Mix Two Layers 'Back Extract'
10:24
Final Results
10:43
Planning an Acid-Base Extraction, Part 1
11:01
Solute Type: Neutral
11:02
Aqueous Solution: Water
13:40
Solute Type: Basic
14:43
Solute Type: Weakly Acidic
15:23
Solute Type: Acidic
16:12
Planning an Acid-Base Extraction, Part 2
17:34
Planning an Acid-Base Extraction
17:35
Performing an Extraction
19:34
Pour Solution into Sep Funnel
19:35
Add Second Liquid
20:07
Add Stopper, Cover with Hand, Remove from Ring
20:48
Tip Upside Down, Open Stopcock to Vent Pressure
21:00
Shake to Mix Two Layers
21:30
Remove Stopper & Drain Bottom Layer
21:40
Reaction Work-up: Purify, Isolate Product
22:03
Typical Reaction is Run in Organic Solvent
22:04
Starting a Reaction Work-up
22:33
Extracting the Product with Organic Solvent
23:17
Combined Extracts are Washed
23:40
Organic Layer is 'Dried'
24:23
Finding the Product
26:38
Which Layer is Which?
26:39
Where is My Product?
28:00
Tips, Tricks and Warnings
29:29
Leaking Sep Funnel
29:30
Caution When Mixing Layers & Using Ether
30:17
If an Emulsion Forms
31:51
Extraction Lab

14m 49s

Intro
0:00
Step 1: Preparing the Separatory Funnel
0:03
Step 2: Adding Sample
1:18
Step 3: Mixing the Two Layers
2:59
Step 4: Draining the Bottom Layers
4:59
Step 5: Performing a Second Extraction
5:50
Step 6: Drying the Organic Layer
7:21
Step 7: Gravity Filtration
9:35
Possible Extraction Challenges
12:55
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Lecture Comments (29)

1 answer

Last reply by: Professor Starkey
Mon Jun 15, 2020 3:30 PM

Post by Maryam Fayyazi on February 6, 2020

Hi, is there a way to distinguish between an alkane and tertiary amine IR?

1 answer

Last reply by: Professor Starkey
Fri Jun 5, 2015 1:18 AM

Post by Lyngage Tan on June 4, 2015

hi dr starkey at 28:37  are peaks 1932 and 1853  Ar ripples?

1 answer

Last reply by: Professor Starkey
Sat Feb 28, 2015 12:53 AM

Post by Sammy Hajomar on February 26, 2015

Why can't I fast forward to a section I want to in the video?

1 answer

Last reply by: Professor Starkey
Sat Nov 1, 2014 11:29 PM

Post by Brijae Chavarria on November 1, 2014

Hello, I'm not sure if it's just my computer, but sometimes when I download the lectures, certain slides are missing. In this lecture specifically, the IR Spectrum of alkenes is missing. Any input? Thanks.

1 answer

Last reply by: Professor Starkey
Sun Oct 26, 2014 12:51 AM

Post by Suceti Martinez on October 23, 2014

I can't see the video. it says network error

2 answers

Last reply by: Professor Starkey
Sun Sep 21, 2014 6:55 PM

Post by Kara Harris on September 21, 2014

Are there print-outs for your all of your lectures? It would be so much easier to follow along if I had the spectrums in front of me. Thank you.

1 answer

Last reply by: Professor Starkey
Wed Feb 19, 2014 12:12 PM

Post by xyla williams on February 18, 2014

FYI - in the IR section (part 1), the lecture slide labeled 1-pentene, pulls up the pentane spectrum

1 answer

Last reply by: Professor Starkey
Tue Feb 4, 2014 8:55 PM

Post by Caroline Hubbard on February 2, 2014

In example 7, would you also include the C single bonded to the O of the OH group at 1250-1350?

1 answer

Last reply by: Professor Starkey
Mon Sep 30, 2013 10:58 AM

Post by Kristine Penalosa on September 25, 2013

Is anyone having trouble opening the exercise files?

1 answer

Last reply by: Professor Starkey
Wed Feb 20, 2013 9:55 PM

Post by Ryan Rod on February 18, 2013

how about ethers and amide? or in general other compounds with carbonyls??

1 answer

Last reply by: Professor Starkey
Sun Feb 17, 2013 5:27 PM

Post by Matthew Wonchala on February 16, 2013

During the IR example of 2-butanone, did you mislabel a ketone and carbonyl? I was under the understanding that a ketone was simply a C double bonded to an O, and that a carbonyl was when another C bond was present. I sounded like you explained that backwards though.

0 answers

Post by Marina Bossi on December 12, 2012

(that is, if it fits into both of those areas)

2 answers

Last reply by: Vineet Kumar
Mon Sep 23, 2013 7:27 PM

Post by christopher coppins on December 7, 2011

hello professor Starkey, your by far one of the best techers ive seen that teaches a chemistry lecture hands down. You are getting me through organic 1 an organic 2,so i just wanted to thankyou for that. My question to is, im a pre med bio/chemistry major an i have to take analytical chemistry as well as physical chemistry soon an i need lectures that cover those topics, so i wanted to know do you or do you know where i can find lectures like your's are but in the topics i need? thanks in advance...

1 answer

Last reply by: Professor Starkey
Thu Nov 10, 2011 11:10 AM

Post by Clint Khemkhajon on November 6, 2011

You saved me!

Infrared Spectroscopy, Part I

Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.

  • Intro 0:00
  • Infrared (IR) Spectroscopy 0:09
    • Introduction to Infrared (IR) Spectroscopy
    • Intensity of Absorption Is Proportional to Change in Dipole
  • IR Spectrum of an Alkane 6:08
    • Pentane
  • IR Spectrum of an Alkene 13:12
    • 1-Pentene
  • IR Spectrum of an Alkyne 15:49
    • 1-Pentyne
  • IR Spectrum of an Aromatic Compound 18:02
    • Methylbenzene
  • IR of Substituted Aromatic Compounds 24:04
    • IR of Substituted Aromatic Compounds
  • IR Spectrum of 1,2-Disubstituted Aromatic 25:30
    • 1,2-dimethylbenzene
  • IR Spectrum of 1,3-Disubstituted Aromatic 27:15
    • 1,3-dimethylbenzene
  • IR Spectrum of 1,4-Disubstituted Aromatic 28:41
    • 1,4-dimethylbenzene
  • IR Spectrum of an Alcohol 29:34
    • 1-pentanol
  • IR Spectrum of an Amine 32:39
    • 1-butanamine
  • IR Spectrum of a 2° Amine 34:50
    • Diethylamine
  • IR Spectrum of a 3° Amine 35:47
    • Triethylamine
  • IR Spectrum of a Ketone 36:41
    • 2-butanone
  • IR Spectrum of an Aldehyde 40:10
    • Pentanal
  • IR Spectrum of an Ester 42:38
    • Butyl Propanoate
  • IR Spectrum of a Carboxylic Acid 44:26
    • Butanoic Acid
  • Sample IR Correlation Chart 47:36
    • Sample IR Correlation Chart: Wavenumber and Functional Group
  • Predicting IR Spectra: Sample Structures 52:06
    • Example 1
    • Example 2
    • Example 3
    • Example 4
    • Example 5
    • Example 6
    • Example 7
    • Example 8

Transcription: Infrared Spectroscopy, Part I

Hi; welcome back to Educator.0000

We are going to talk about infrared spectroscopy today--which is a really important tool for analyzing the structure of organic molecules.0002

Now, all spectroscopies work generally the same way: we are going to take our sample; we are going to irradiate it with some kind of energy (in our case, we are going to be using infrared light--that is why we call it IR spectroscopy).0010

And we are going to take a molecule (let's say we have a molecule like this, a molecule of HCl); we are going to hit it with a photon of light.0022

Now, that photon is going to be described in terms of its energy: its energy can be put in terms of its wavelength.0028

And so, we have this constant in the speed of light; and so we see that, if the wavelength gets smaller, the energy increases; so light of a smaller wavelength, a shorter wavelength, is higher in energy.0038

And we are going to be using a different...so this is wavelength, this λ here...and we are going to be using this: this v with a line over it is short for wavenumber.0052

These are in units called reciprocal centimeters; so it's centimeters to the -1.0067

And you can see they have an inverse relationship (so that is where the -1 comes from), and we will find that energy has a direct relationship with these wave numbers.0073

We are going to be using these numbers, reciprocal centimeters, to describe the photons of light that we are using; and what we need to remember is that, as you increase your wavenumber--increase the number--you are increasing in energy.0084

OK, well, what is going to happen is: when this sample is irradiated, when it's hit with just the right energy of light, that energy can be absorbed.0097

And what happens when infrared light is absorbed by a molecule is: it undergoes vibrations; we say that the molecule becomes vibrationally excited.0109

Now, what does that mean?--well, here we have a hydrogen-chlorine bond, so the only motion that can happen is: this chlorine can move closer and away from the hydrogen.0119

We call that stretching of the bond: it stretches and compresses.0128

That molecular vibration is the result of absorption of IR light.0135

Now, how can this help us analytically--how can this help us analyze a sample and learn something about its structure?0141

Well, here is what we are going to do: we are going to irradiate the sample with IR light, and we are going to record the frequencies that are absorbed; so we are going to pay attention to which frequencies are absorbed by the molecules and which ones are not--which ones are just transmitted.0149

OK, because it turns out that certain functional groups have characteristic absorption: so if you have, for example, an OH group in your molecule, OH groups absorb a certain wavelength of infrared light.0163

And so, if we see an absorption at that wavelength, that tells us that our molecule has an OH group on it; so it's going to be...IR analysis is a way for analyzing for functional groups.0177

Now, it turns out that the intensity of the absorption--how strongly the molecule absorbs that light--is proportional to the change in dipole.0188

So, if we have something that is not polar--a bond that is not polar--then it is not going to be something that will absorb IR light.0197

So, for example, let's take a look at a molecule, a more complicated molecule, like carbon dioxide.0207

If we take CO2, and we irradiate it with infrared light, what can happen--how can this molecule become vibrationally excited?0213

Well, one thing it can do is: the CO bonds can bend; the oxygens can bend toward one another; so we can maybe draw that motion like this.0223

And we would describe that motion as bending, and that would be...a certain wavelength of light can be absorbed that will correspond to that motion.0234

Now, another thing that carbon dioxide can do is: we can have stretching of bonds, like we saw here; and so, we can have both of these oxygens stretching and getting longer and shorter, and longer and shorter.0249

Because they are going in sync, we call this a symmetric stretch, symmetric stretching motion; or we can have a motion where, as one carbon-oxygen bond gets longer, the other one gets shorter: we call that an asymmetric stretch or an antisymmetric stretch.0263

Now, it turns out that, because carbon dioxide is a nonpolar molecule, not each of these motions would result in a change in the dipole of the molecule.0289

Now, if you bend the oxygens in one direction, that is going to now make the molecule a polar molecule; so that definitely changes the dipole, and that would have a signal in the IR.0301

OK, but if I were to pull these two oxygens in opposite directions with the same force, that would keep the molecule nonpolar; there would be no change in dipole.0312

And therefore, there would be no absorption--meaning there is no signal.0327

There is no signal in the IR for that motion; but if we were to stretch the molecule like this, where both oxygens move in the same direction, then it is going to have a change in dipole, and we get a signal here.0337

OK, so this is just one little note of all of the peaks that we are going to be observing in the IR spectra: we should recognize that all of the motions we are describing do result in a change of dipole.0350

Otherwise, they wouldn't appear in the spectrum, and we wouldn't even be able to observe them.0363

OK, so let's take a look at various functional groups and see what their IR spectra look like.0371

The simplest compound we can have is an alkane: an alkane like pentane has just carbon-carbon bonds, carbon-hydrogen bonds--there is nothing else there; there is no other really significant functional group--no other atoms besides carbon and hydrogen.0376

And let's see what that spectrum looks like: OK, first of all, though, let's take a look at what an IR spectrum...how they are presented.0390

OK, we can see here that our numbers are shown as wavenumbers, as promised; so the unit here is reciprocal centimeters, or inverse centimeters.0399

And our range is about 4,000 to about 400 (or, in this case, 600).0411

So, that is the typical range of IR that we are interested in, that is going to give these characteristic absorptions that are going to be useful to us to analyze.0417

OK, and what we are showing over here is: we are showing percent transmittance.0428

So, what we are asking is: as this sample is being irradiated with light, how much of that IR light is just being transmitted directly through the sample and not absorbed?0432

And so, up here, we have 100% transmittance, meaning we had 0...so there is always a little bit of absorption here, but a straight line going all the way across here means that our IR light comes straight through, and nothing gets absorbed.0442

Every time we have a dip down from that top line, it means we record that as an absorption; so it's those dips--it is these long peaks, as we call them, that we are going to interpret and try to make some sense of.0458

OK, and down here is 0, meaning no light was transmitted; all of the light of that frequency was absorbed.0473

So, a very, very strong absorption would be one where nearly all of the light is absorbed, and almost none of it is transmitted.0480

OK, so let's see what we are going to expect for an alkane.0490

Well, what kind of bonds do we have that could potentially stretch or bend?0493

OK, well, we have a carbon-carbon bond here; and then we have these carbon-hydrogen bonds, and those are the bond that can do some stretching or do some bending.0499

Of course, with pentane, we have a pretty complicated molecule; so can you imagine the motions this can have when it's vibrating?--it can be wiggling all over the place.0510

It seems like there would be an infinite number of vibrations that it can have.0518

But really, there are just some basic, fundamental ones that we are going to be seeing.0522

OK, the way we characterize this carbon of an alkane: it's a tetrahedral carbon, so it's just a plain old sp3 hybridized carbon.0526

And hydrogens that are attached to sp3 hybridized carbons have this characteristic set of peaks, right here, just below 3,000.0538

So, just below 3,000 reciprocal centimeters, we see all of these peaks; and every time we see that, it is going to tell us that our molecule contains sp3 carbons with hydrogens attached--in other words, plain old alkyl hydrogens or alkane groups.0551

Now, why are there so many peaks?--well, we have groups that are like this one (a CH3); we have groups like this one (that are CH2s); and for each of these, we can have symmetric stretching (where they are going in the same direction); we can have asymmetric stretching (where they are going in opposite directions).0570

And so, this is something that results in several little peaks, but we don't have to break them all down; we could just say this whole region that is just to the right of 3,000 tells us that we have sp3 CH's.0587

Now, these peaks here represent CH bending, and that is where, rather than stretching, the molecule is just kind of tipping and rocking and that sort of motion; we are bending one bond with respect to another.0604

OK, and we are not going to see an awful lot of these peaks; we are not going to be able to pick out a lot of these peaks, because bending is a very easy motion--very low-energy motion for a molecule to have--it is very easy for a molecule to bend.0624

Imagine taking a rubber band; and if we are trying to bend a rubber band versus stretch a rubber band, which is the harder process to do?0637

It is more difficult to stretch the band, which means that is going to take more energy to put in there; and so that is why we see that to stretch a bond takes about 3,000 reciprocal centimeters, where to bend it, it just takes something like 1,400.0644

Remember, as you decrease your wavenumbers, you decrease your energy.0658

So, because this is such an easy motion to have happen, what we end up with is a very complicated region down here; and this whole region is so complicated, we will often see lots and lots of peaks--see all these little wiggles?0662

This is called the fingerprint region, and it is called the fingerprint region because it is so complex that it ends up being unique for a given molecule.0679

Just like your fingerprint is unique for each individual, the fingerprint region is unique for a molecule; so this is very handy in analysis; let's say we are analyzing a drug sample or something isolated, and we want to see if it's an illicit drug or something.0697

What we could do is: we could take an IR of that sample, and then we could screen it against a library of known compounds; and if we find a match in that fingerprint region with a known compound that we have in our spectra library--in our database--then we would have proof of the identity of the molecule.0714

OK, so in general, IR spectra don't give us a lot of information--they just tell us what kind of functional groups we have in here.0733

However, if we had computer tools to be able to analyze the fingerprint region--we couldn't do this just by looking at it, but it is possible to get absolute identifications of molecules, based on their fingerprint region.0743

OK, but when we look at this overall spectrum, the only thing that is really of interest that we are going to be picking out is this peak down here, below 3,000; and it just tells us that we have alkyl CH bonds in our molecule.0757

It is a pretty boring spectrum; there is not much to it; and if this is a spectrum of pentane, what if we looked at the spectrum of hexane or heptane or decane?0770

It is actually going to look very, very similar to this; so it is not going to tell us exactly which alkane we have--it is just going to tell us that we have an alkane, and we have no other significant functional groups in there.0781

OK, what happens when we have an alkene?--an alkene means we have a carbon-carbon double bond, and so how is this going to affect our spectrum?0795

Well, first of all, we can see that we still have our CH's that are attached to an sp3 hybridized carbon; so where did we find those in our spectrum?--we found those just below 3,000, and it looks like we still have those peaks here.0807

So, we can go ahead and label these as sp3 CH bonds; we don't have to call it a stretch--it is actually the bonds stretching--but we can just indicate that the functional group of interest here is an sp3 CH.0828

Well, what we have new that is in our structure: this is a new peak, right here, just above 3,000; and this comes from having these bonds.0844

We have hydrogens that are not on sp3 hybridized carbons; we have hydrogens that are on sp2 hybridized carbons; this is a trigonal planar carbon; this is sp2 hybridized; and so, when you have hydrogens attached to those kinds of carbons in your molecule, the IR spectrum is going to show it by having a peak just above 3,000.0854

So, we will label this peak as an sp2 CH; so when I look at this spectrum, I know that my molecule must have both hydrogens attached to alkene-type carbons or hydrogens attached to alkane-type carbons.0875

What else is there in this spectrum?--well, again, kind of a noisy fingerprint region: we are not going to try and pick out all of those peaks.0890

The other interesting peak is right here, around 1,600; it is where we find carbon-carbon double bonds that are stretching; so this carbon-carbon double bond--when we hit it with infrared light of 1,640 wavenumbers, that is exactly the energy that is needed to cause that carbon-carbon double bond to stretch.0897

And so, we see a peak there.0922

OK, you notice, though, that this is a very weak signal; and so, we are not always going to be able to find that; that is also not a very polar bond, is it?0925

So, there is not a big change in dipole; and so, a lot of times, it is difficult to find carbon-carbon double bond peaks, and sometimes they disappear altogether; if this is symmetrical, we won't even have that peak.0932

Now, an alkyne is what we call it when we have a carbon-carbon triple bond; let's analyze this structure.0951

We see that we still have this region of the molecule that kind of looks like an alkane; it has sp3 carbons with hydrogens on it.0956

And so, we expect to find that on our spectrum; where is it?0966

We are going to always look at this 3,000 mark; we are going to go to the right of 3,000, and sure enough, we are going to see a variety of peaks there, typically.0970

I'll label that sp3 CH; now I'm labeling this, and it's a good idea to have these spectra printed out, so you can label them, too, and get some practice in that, because that is one of the goals of learning about IR spectroscopy: not only to understand the theory of it, but to be able to interpret a spectrum.0979

And you are expected to mark it up and label peaks and use that to fully interpret or explain what you see in an IR spectrum.0996

OK, so what else is in this spectrum--what other kinds of hydrogens do we have in the structure?1007

The hydrogens are always going to be really important in our spectra; so, we have some hydrogens that are attached to sp3 hybridized carbon, but we also have a hydrogen at the end of the molecule here that is attached to an sp hybridized carbon.1012

And so, that is going be a significant peak in the IR, and that is going to show up right here, even further to the left of 3,000--right here at 3,300, this peak comes from the sp carbon with the hydrogen on it.1027

That bond is stretching, and that is going to show up around 3,300.1042

OK, so we can see a trend here: the sp3 is just below 3,000; sp2 is a little higher; and sp is a little higher still.1046

We have sp and then sp2 and sp3; we don't have any peaks here for sp2, because this molecule has no sp2 hybridized carbons--so it can't have any hydrogens on those.1055

OK, the other interesting thing that is in this structure is right here--this peak at 2,200.1064

It comes from the carbon-carbon triple bond: when you have a carbon-carbon triple bond, and we cause that triple bond to stretch--those carbons to get further away from each other and closer together--that signal shows up around 2,100, 2,200, somewhere around there.1070

Even though this is a very small peak, normally this is a pretty empty part of the spectrum, and so it should be easy to pick out when you do have a triple bond.1086

A carbon-carbon triple bond looks like this; a carbon-nitrogen triple bond comes at about the same region.1094

That is what an alkyne looks like, like pentyne.1100

How about if we had an aromatic compound?--now, we use the word "aromatic" a lot when we are talking about IR spectroscopy, and when we use the word "aromatic," we are talking about something like benzene.1106

Benzene is the molecule when we have a 6-membered ring with three π bonds in that--alternating π bonds.1119

That is a very special molecule; it's called benzene; and so, when we have derivatives of benzene (meaning we have groups attached to any of those carbons), we describe those as aromatic compounds, because benzene is an aromatic compound.1127

There are other things besides benzene and benzene derivatives that are aromatic, but for now, in the introductory stages, when we are first learning about IR, we will kind of use these two synonymously.1141

Any time we are talking about "aromatic," we mean benzene or phenyl (we call it a phenyl group when you have a benzene as a substituent--something attached to a benzene--we call it a phenyl ring).1154

So, benzene itself means that you have this compound with 6 carbons and 6 hydrogens; we can have substituted benzene or benzene derivatives, or we could have a benzene phenyl ring attached--we call it the phenyl group.1166

OK, so any time you see the word "aromatic" (sometimes this is abbreviated Ar for aromatic), you need to picture the benzene ring.1184

Here is an example of an aromatic ring: this is called methylbenzene, because it has a CH3 attached to the benzene.1194

What do we expect to find in its IR spectrum?--well, we saw that C-H bonds are always very important: what kinds of C-H bonds do we have?1200

We have this carbon; it's an sp3 hybridized carbon, so we expect to see these hydrogens stretching symmetrically, asymmetrically.1209

And where do we expect to find those?1220

OK, if we kind of highlight that 3,000 line, just below 3,000 is where we find our sp3 hybridized CH's; so these peaks.1223

And what other kinds of hydrogens do we have?--well, there is a hydrogen at each one of these positions, and so on; and the hybridization of an aromatic ring (like benzene) is sp2 hybridized.1235

Where do we expect to find that?--that is going to appear just above 3,000; this is where we find the sp2 CH's, and sure enough, we see some peaks here.1248

Now notice: not every peak is labeled; sometimes the computer picks up a peak and labels it with a number; sometimes it doesn't.1257

So, don't worry about whether or not a peak is labeled; just focus on whether or not a peak is present--that is what is important here.1264

So, when we talk about sp2 hybridized carbons, that could be an alkene, meaning just a random carbon-carbon double bond; or it could be a double bond within a benzene ring; so it could be an aromatic peak.1272

Now, another interesting thing that we see for aromatic compounds are these peaks down here.1286

Now, you notice this little pattern up here: we have 1, 2, 3, 4 peaks--we have this little ripple.1292

Sometimes, this is described as a little aromatic ripple in this area.1300

And the other interesting thing that we see here are these two peaks, and we are going to get very strong peaks in these regions around 700 and 750 every time we have a benzene ring with this substitution pattern.1305

And the way I would describe this benzene ring is: I have benzene with just one group attached.1324

This is called a monosubstituted aromatic.1328

This is called a monosubstituted aromatic: methylbenzene is an example of that.1337

Every time we see that, we get these two peaks; and these two peaks result in these four peaks--this little ripple up here.1342

This is just something you can kind of look for: normally, this is pretty flat, but when you see this little ripple here, and we can look to this area, if we think we have a benzene ring, this is going to tell us something about the substitution pattern.1352

Now, what is this--why do we have these signals here?1366

Well, these are called out-of-plane bending motions.1369

And I said that bending absorptions are usually not very significant, because they come in the fingerprint region, and that is certainly true.1375

OK, but these aromatic ones are usually so strong that they are very significant signals, and you can kind of pick them out as a needle in the haystack.1383

OK, and what is happening here is: benzene and other aromatic rings are planar, and so, what can happen in one of the motions called an out-of-plane bending is: one of the molecules wobbles like this.1391

And, depending on how many groups are attached to that benzene, that wobbling is going to be happening at slightly different frequencies.1406

OK, so when it's monosubstituted, we get these two peaks at around 700 and 750.1414

Now, all of these numbers that I am rattling off, by the way, as we go along--these are things that are going to be made available to you in tables called correlation charts; and so, there is a sample one of those in the handout; we will look at that a little later.1418

I am just referring to these numbers now, but you will be able to look those up at a later time.1431

OK, so a monosubstituted aromatic looks something like this: let's take a look at some other substitution patterns to see what they might look like.1436

Here is an example of one of these tables.1447

When it's monosubstituted, meaning there is just one group, we are going to get these out-of-plane bending peaks somewhere around 750 and somewhere around 690.1449

If it is disubstituted, there are three different ways you can arrange two groups on a benzene ring.1458

If they are right next to each other (1,2), we describe that as being ortho--having an ortho relationship.1464

And when they are right next to each other, that motion--that out-of-plane bending--changes a little bit, and we now get just a single absorption at 750.1471

And, if they are 1,3 to one another, we call that the meta relationship; a meta disubstituted benzene ends up with three peaks around 880, 750, and 690.1482

And when the two groups are opposite each other, we call that 1,4 disubstituted, or para disubstituted (para substituted ring); then, we get just a single peak at 815.1494

OK, and again, these numbers--you don't have to worry about where they come from, or you don't have to memorize them; they have to do with the relationships of the hydrogens that are on the aromatic ring and the type of out-of-plane bending.1506

Sometimes, we called these oop peaks--out-of-plane bending peaks.1520

OK, so we saw an example of the monosubstituted; let's take a look at some others.1526

This is called dimethylbenzene; if it's 1,2 dimethylbenzene, or ortho dimethylbenzene, we said we are just going to get one peak in this fingerprint region.1531

And notice how, in the fingerprint region, this one peak really does stand out as a very strong peak; this tells us we have ortho disubstituted; we get a peak somewhere around 750.1546

OK, and I forgot to explain where this little aromatic ripple comes from.1556

What happens is: whatever pattern we have down here for the out-of-plane bending--if we absorb twice that amount of energy, we can get that motion to be more intense, and we get a second absorption that is about twice the frequency.1562

So, whatever pattern we have here, we have a concomitant pattern; we have another related pattern that we can pick out.1580

The pattern for an ortho disubstituted aromatic ring looks a little different than the pattern for the monosubstituted; remember, the monosubstituted had a nice 1, 2, 3, 4 look, and the ortho is a little more wiggly.1587

OK, but that is what our ortho looks like; what other peaks do we expect here?1603

Well, we expect the usual: this area is going to look the same, regardless of the substitution pattern; we still have our sp2 CH stretches and our sp3 CH stretches.1607

But the way I can tell that this molecule is an aromatic compound, and not just an alkene, is because it has this little aromatic ripple, and I can pick out this out-of-plane bending peak here.1623

When we have a 1,3 disubstituted pattern, that is called the meta relationship.1636

And when they are meta, we now expect to have these two peaks: about 690 and about 700.1644

OK, and then, there is a third one, although it is usually not so easy to pick out: it is this one up here.1654

And so, if you can't see it right away, that is OK, because these two are a little more obvious.1660

And what do we expect to find?--again, we have sp3 hybridized CH's; we have sp2 hybridized CH's; so here we have those peaks: an sp3 CH and an sp2 CH.1667

OK, be careful with your labeling: you don't want to get lazy here and just label this as an sp3.1682

All right, there is no such thing as an sp3: that is not a functional group.1687

What we are saying here is: by the presence of these peaks, we know that the molecule has sp3 carbons with hydrogens attached to those, and that stretching motion of that C-H bond occurs somewhere very close, around 2,900 reciprocal centimeters--just under 3,000.1690

OK, so it is an sp3 CH--the actual functional group that we are identifying here.1711

This is an sp2 CH.1717

And then, finally, the para disubstituted--when it's 1,4, we call that para; and the para has just this single peak somewhere around 800.1721

OK, and again, this is something we can kind of look for to dig out evidence; it is not something that is necessarily going to jump right out at us when we see it.1735

And the para pattern looks something like that: that is also a characteristic that we expect to find for our little aromatic ripple area.1744

We still have our sp2 CH and our sp3 CH.1756

OK, so these are called out-of-plane bending peaks that we can use to pick out the substitution patterns of aromatic rings.1762

OK, what other functional groups can we look for?1777

So far, we have really just looked at the C-H bonds, the different kinds of C-H bonds we might have in a molecule, and how they all vary--if we have alkanes or alkenes or aromatic, or maybe an alkyne triple bond.1779

OK, well, if we have an OH group, we call those molecules alcohols, and they are very characteristic in an IR, because what we can look for is that OH bond itself stretching.1790

That comes right here--this big, broad peak is the OH stretch.1806

We call it that because it is literally the O-H bond stretching.1816

It comes right here typically, around 3,300; but notice that it is very broad--and this is characteristic of an OH functional group and an OH peak.1820

It is very broad, meaning it starts all the way here around 3,600, and it doesn't end until right here, around 3,100; so rather than being sharp and narrow, like the peaks we have seen before, it's very broad and spread-out.1829

OK, and that is because this can undergo hydrogen bonding with another molecule of 1, 2, 3 ,4, 5...pentanol.1843

This is a very strong partial minus; the hydrogen on an oxygen is a very strong partial plus; and so, what we have here is hydrogen bonding between molecules, and that affects the spectra, and we end up seeing this broadening of the peak.1853

OK, so that is what we can look for for an alcohol; let's go ahead and see if we can find anything else in this spectrum.1873

What else do we expect to find?--well, we have our alkyl group here, and the way we would see that are these four peaks to the right of 3,000, just below 3,000; those are our sp3 CH's.1879

Notice, we are going to see that in almost every single IR spectrum, because almost every single organic molecule has some kind of alkyl group on it, right?--a methyl, ethyl, propyl, butyl, something like that.1894

And so, nearly every IR spectrum is going to have that peak; and so, you should be used to seeing that, even without a correlation table; you should know to look right at 3,000 and analyze that area very carefully.1906

What else is there?--well, we can also point out: there is another bond that is unique in this molecule, and that is this C-O bond.1920

And C-O bonds, C-O stretches, show up at around 1,050 or so.1927

And again, that is a stretch: that is where the C-O bond is getting longer and shorter, and it usually comes around 1,050.1934

But because this is in the fingerprint region, it is not so easy to pick out; it is not always a strong peak, either.1944

So, in this case, we can see it with pretty good confidence, and we can label it; but sometimes, we are not going to be able to do it quite as easily.1950

Now, if we have an amine--we call it an amine when we have a nitrogen in our compound--here we have NH groups, and again, these can hydrogen bond, so they are going to be somewhat similar to an OH, and they are going to come at the same region, somewhere around 3,300.1961

OK, but we can see that they are going to be typically weaker than an OH: an OH is a nice, strong peak; that means it goes pretty low--there is a very strong absorption, because it's a very polar bond.1982

But the NH is usually a little weaker; and notice that we have two peaks here, and that is because this is an example of a primary amine: it has just one alkyl group attached to the nitrogen.1995

And we call those amines primary amines; and so, a primary amine must have an NH2, and we can have those hydrogens stretching either symmetrically or asymmetrically.2014

So, if they are stretching symmetrically, we get one absorption; if they are stretching asymmetrically, we get a second absorption; so because of this NH2, we end up getting this little double set of peaks here.2032

Notice, both of these are going to show up, because this is a polar molecule, and both of these motions in this case result in changes in dipole.2047

So again, we are going to see every N-H bond that is in the molecule; we are going to see it as a stretch.2054

But it is usually a little smaller here.2059

OK, is there anything else in the spectrum we can label?--sure enough, we have our usual sp3 CH; nothing else here of note.2062

The C-N bond...the C-O bond was difficult to find; the C-N bond is not diagnostically useful, so the only thing that is interesting in this amine (besides the sp3 CH) is the NH stretch.2072

Now, depending on the type of amine, this peak is going to look a little different: let's take a look at some examples.2086

OK, so a secondary amine is what we call it when we have two alkyl groups or two R groups; that is why we call it a secondary amine.2092

And so, we know nitrogen likes to have three bonds; so that means there is just one hydrogen attached here, and so our peak looks a little different; there is just one because that NH stretch--there is no other motion that could be happening there.2106

We could have this single NH stretch.2118

And so, this is our NH bond; that is the NH that is stretching, so that looks a little...secondary amines look a little different than our primary amine; and again, we have this whole big mess here as a result of our sp3 hybridized CH's.2121

OK, all of this other stuff in the fingerprint region, we are not going to be worrying about.2142

How about if we had a tertiary amine?--a tertiary amine has three alkyl groups; so what will we look for in its spectrum?2149

Do we expect to find an NH signal?--it looks pretty empty here--it looks like we have just a total transmission; there is no absorption at 3,300.2158

Why does this amine have no absorption at 3,300?--because that absorption was the result of the NH bond in the amine stretching; this has no NH bond, and therefore, there is no absorption there.2168

So, this amine looks very much like any other alkane; all we have here are sp3 CH's and nothing else.2183

So, an amine is only interesting in the IR if it's a primary or secondary amine, because it is the NH bond that we can look for and pick out.2192

OK, how about a ketone?--a ketone is what we call it when we have a carbonyl (a C-O double bond is called a carbonyl), and when we have a carbon attached to either side (like we do here--we have a methyl here and an ethyl here), we call it a ketone.2203

And the C-O double bond is very polar; and so, when it stretches, there is a big change in dipole, which means a carbonyl group has a really strong absorption of IR light.2227

That means we are going to get a really huge signal.2240

And where does it show up?--it shows up right here; somewhere around 1,700 is where we are going to see our C, double bond, O.2242

You could just label it as a C, double bond, O; and that is where we see our carbonyl, and I want you to notice that it is incredibly strong.2249

The carbonyl peak is going to be your strongest peak in the entire spectrum.2257

OK, you can't miss it; if you are ever looking at a peak somewhere around 1,700, and you are looking and you are saying, "That might be a carbonyl--do you think that's a carbonyl?"--it is not a carbonyl.2263

OK, unless it is so big that it almost touches the bottom line, and you have a complete absorption, then it is not a carbonyl; so a carbonyl is something that you should never mistake in an IR spectrum.2272

And it is another one that is kind of handy--as you work with IR's, you will get to know this number very readily; it always comes around 1,700.2285

Somewhere around 1,700...now, it can shift a little to the left or the right, depending on whether it is a ketone or an aldehyde, or exactly what groups are attached to either side.2296

If you have a double bond attached on one side, so that the carbonyl is conjugated with other π bonds, that shifts it to a lower number.2306

So, it can move somewhere around 1,700, but it's always in that range.2314

OK, so that is what a ketone looks like; what else did we have in this ketone?--well, we have our usual sp3 CH; so there is nothing else too interesting to label.2319

Another thing I want to point out is: take a look at this little peak.2327

Now, you might look at that and say, "Oh, is that maybe an NH, or is that an OH, because it's coming around 3,300?"2330

OK, well, definitely not an OH, because an OH is another thing you are not going to miss: it's a nice, big, broad peak.2337

OK, an NH is usually smaller; but what this peak actually results from is: this carbonyl is so strong--and once again, if this were to absorb twice the amount of energy for that carbonyl to stretch even further, you would see a second signal at about twice this.2344

OK, so this is at 1,700; this is right around 3,400; and so, this we describe as an overtone for the carbonyl.2367

And so, we can ignore that; it just means...it is the same functional group we already identified; it's the carbonyl.2378

I just want to call attention to it, though, because sometimes (because carbonyls are so strong)--sometimes this peak can look pretty big, and might give you a false idea that you have an OH or an NH.2384

But there is a little warning: if you have a carbonyl here, you want to be skeptical of a peak up here--that it could just be the overtone of the carbonyl, like it is in this case--there is no other functional group present, so that must be just the overtone.2395

Now, if you have an aldehyde, how is that going to differ from a ketone?2411

Well, what makes an aldehyde an aldehyde is that, attached to the carbonyl, we have a hydrogen.2415

OK, so that means this carbon-hydrogen bond is unique: remember, all the hydrogens in our structure are going to be important for IR.2423

And now, it is not just attached to an ordinary sp2 hybridized carbon, like we have in an alkene or a benzene ring; it is attached to a carbonyl--that is a very unique type of carbon.2430

We are going to call this a carbonyl...I'm sorry, let's call it an aldehyde CH; it's a very special kind of bond.2443

And, when you have an aldehyde, that shows up right here: we are going to get two peaks (one of them was labeled, and one of them was not).2456

It comes at about 2,850, and around 2,750, we get these two peaks that kind of look like vampire fangs--I always see them as vampire fangs.2465

And they are usually weak like this--they are usually pretty small--so it is very easy to overlook these at first.2476

OK, this peak I see very clearly; but this one is almost totally obscured by this larger peak; so you have to look very carefully.2482

OK, but both of those peaks combined, we are going to label as an aldehyde CH: that tells us that we have an aldehyde.2491

Now, what else should we find in this spectrum?2499

If you have an aldehyde, that means you must have a carbonyl; where do carbonyls show up?--right around 1,700--strongest peak, biggest peak in the whole spectrum.2502

So, no missing that: there is our carbonyl.2513

And what else does this aldehyde have?--well, the rest of these peaks up here, just below 3,000--these are sp3 CH's.2516

OK, so that is what an aldehyde looks like.2525

Here is another case where this looks like a pretty significant peak up here--this looks pretty decent in size; but because we have a carbonyl, we are going to look up at that and recognize that just as an overtone--the carbonyl overtone.2529

Even though that is pretty big here, it is still no other additional functional group--it is just that carbonyl absorbing twice the energy to cause that increase in energy.2544

OK, one other type of carbonyl compound we will take a look at--a couple of others, actually: we call it an ester when the carbonyl has an O-R attached to the carbonyl carbon; so we have just a carbon group over here, and an oxygen with an alkyl group.2560

All right, so we could describe this as an O-R group.2577

And so, what does that look like?--well, we still have a carbonyl; OK, that carbonyl is going to be somewhere around 1,700; we see it shifting up a little higher now, compared to a ketone or an aldehyde.2582

Esters come a little different: you can get a table of just carbonyl peaks, on where they come, depending on the exact type of groups attached to that carbonyl--what functional group you are looking at.2597

OK, but somewhere around 1,700--really, really strong peak, clearly the carbonyl.2609

OK, we also expect--these are all sp3 hybridized carbons--all the hydrogens in this molecule are attached to sp3 hybridized carbons.2614

We expect to find those right here, just below 3,000.2622

And the only other thing that is interesting in an ester is: we have a C-O bond here, and we have a C-O bond here, and these are different C-Os.2627

And so, sometimes, we could pick those out, or we should try and find those.2639

Remember, a C-O comes somewhere around 1,050, so if we look around 1,050, we have a nice, strong one here: 1,200 and 1,080; so those are probably our two C-O single bonds.2642

A C-O double bond is called a carbonyl that comes around 1,700; a C-O single bond is somewhere around 1,050.2657

OK, and a carboxylic acid is the last functional group we are going to look at, and what makes a carboxylic acid functional group?2668

Well, you have an OH group; OK, but it is not an alcohol, because that OH is attached to the carbonyl; so this whole functional group together is described as a carboxylic acid.2677

OK, now what is it going to have in common with what we have seen before?--well, any carbonyl-containing compound is going to have a carbonyl stretch, and that is going to come somewhere around 1,700, so here it is; there is our carbonyl.2689

OK, and it is also going to have an OH stretch; but this is going to be a little different from an alcohol OH, because this is extremely polar, and it can very effectively hydrogen bond--in fact, so much so that two carboxylic acids can come together an dimerize with very strong hydrogen bonding.2705

And so, what happens is: remember, the OH was a very broad peak: well, a carboxylic acid gets even broader: in fact, it turns out that it is this whole peak here--we could abbreviate a carboxylic acid as RCO2H, so we could call it a carboxylic acid OH, or would label it as...we could give it the name "carboxylic acid OH."2726

I don't want to just label it as an OH; it is the OH bond that is stretching, but there is more information in the spectrum, so I want to make sure I label it completely.2752

I can tell from the shape of this OH that it is a carboxylic acid OH; so I want to make sure I note that in my labeling here.2761

And remember, a normal alcohol was somewhere around 3,300, but a normal alcohol, just so we can compare it, looks something like that.2771

This would be an ROH, or an alcohol OH; so if that OH was attached to an ordinary alkyl group, then we expect to have this nice, broad peak, but it starts and then it stops, and then we have our CH's.2781

Here, the OH starts around 3,500 and goes all the way down to 2,400--really, really broad.2798

That is what a carboxylic acid does; in fact, carboxylic acids can get really, really messy and ugly; so if you ever find a spectrum where it is just a total disaster in this area, and really weird, and you don't know what has happened, look for a carbonyl; think about whether or not you maybe have a carboxylic acid that could answer some of those strange questions.2807

OK, now what do we see peaking out below this whole carboxylic acid OH?2828

Well, sure enough, we can pick out these little jagged peaks that are partially obscured, but we can see them at the bottom here; those, of course, would be our sp3 CH's, because we have an alkyl group attached to our carboxylic acid part.2833

OK, so just to give you an idea of the significant functional groups that we are going to be seeing, we have gone through lots of examples.2849

OK, and as promised, you are going to be given some kind of correlation chart whenever you go to work with IR problems.2857

Now, as you gain experience, a lot of these numbers and different areas are going to kind of become more second nature to you.2866

But, in the meantime, you will always have a chart like this...you will almost always have a chart like this to refer to.2875

So, make sure you use it as you are working on IR problems.2880

OK, so as we are looking from the highest numbers of things we saw in the very far left of the spectrum (where our OH and our NH--remember those? came), around 3,300--somewhere in that region, and it was very broad--that is characteristic of the shape of that peak.2884

An S, the letter S, in one of these correlation charts, means that it's strong; M stands for medium; and W stands for weak; or sometimes, you see a V--that means variable intensity.2906

Sometimes it is strong; sometimes it is not.2922

OK, so you might see that--rather than just "where is it?" it tells you something about the shape of the peak, typically.2925

And all of these are going to be sharp peaks (they go up and down), except for the OH and the NH; because of that hydrogen bonding, they spread out; those are broad peaks.2931

OK, if we look at the CH's (sp, sp2, sp3), notice that 3,000 is the very important cutoff between the sp2s just to the left of it and the sp3s just to the right of it.2940

And the sp's show up around 3,300.2957

Now, if the sp CH shows up at 3,300, and the alcohol shows up at 3,300, how do we know which one we have?2960

Well, this, again, comes to the shape of the peak: the OH is going to be very broad, where the sp CH is going to be very sharp--it is going to be very narrow.2968

Those actually do look quite different from one another.2977

OK, the other type of CH that is interesting--so CH's are the only one that we describe by the type of carbon that they are attached to.2980

Everything else...an OH is an OH; an NH is an NH; but if it's a CH, we have to describe exactly what kind of CH it is, because then it appears at different places on the spectrum.2991

So, it could be sp or sp2, like in an alkene or in a benzene ring, an aromatic compound; sp3 means it's just a plain old tetrahedral carbon, alkane.3001

And then, an aldehyde CH means that the hydrogen is attached to a carbonyl carbon--directly attached to the C-O double bond; we call that the aldehyde functional group.3011

OK, as we move down around 2,200--somewhere around 2,200 is where have our triple bonds (carbon-carbon triple bond, carbon-nitrogen triple bond).3021

Around 1,600 is where we have our carbon-carbon double bond; again, this is variable.3030

It can be strong, or it can be very weak; and especially these carbon-carbon double bonds--these will disappear entirely if it is a symmetrical molecule.3034

OK, so if we are looking at a carbon-carbon triple bond, and you have the same group on either side of that triple bond, then when that stretches, there is no change in dipole; we get no absorption of IR light.3057

So, sometimes you might be looking for a peak at 2,200, and there is nothing there.3066

That doesn't necessarily mean that you have no triple bond; you might just have a symmetrically substituted triple bond--the same can be true for a carbon-carbon double bond.3071

OK, carbonyl stretch--this is a big one, because this is our biggest, strongest, most obvious peak there is; that comes around 1,700.3081

And then, our CO single bond stretches come around 1,050; they're typically pretty strong, but sometimes they are just hard to pick out, because now we are in that fingerprint region, where we have all sorts of bending and wobbling going on in our molecule, so it's just a very messy part of the spectrum.3090

OK, so we will use a chart like this when we go to interpret IR spectra; and before we get to interpreting IR spectra and breaking down a spectrum if you are given one, first let's take a look at some sample molecules to see if we can predict what we would find in the IR spectrum.3105

You might want to pause this and try it on your own: see if you can pick out the significant functional groups--and not only pick out the significant functional groups, but then use your correlation chart to predict approximately where you might find that peak in the IR spectrum.3129

OK, so how about our first molecule?3146

Definitely, the C, double bond, O, jumps out at me; so I know that is going to be in my spectrum.3150

I have a carbonyl somewhere around 1,700 reciprocal centimeters, or inverse centimeters--somewhere around 1,700.3156

What else is in this molecule?--there is not much else; we just have these alkyl groups.3165

And so, what do we see in the IR spectrum of an alkyl group?3172

The carbon-carbon single bonds--not diagnostically useful: there is nothing we would see for that.3177

OK, but the hydrogens in the molecule are always important; so how would you describe these hydrogens that are attached here and here and here?3182

They are attached to sp3 carbons, so we would call that an sp3 CH; that is how you would label that peak, when you saw the spectrum: this is an sp3 CH, and where do they show up?--just below 3,000.3190

That is what we would expect to find for a ketone.3208

How about this next one?--this next one is an alkyne; we have an alkyne...let's start with our CH's--what kind of CH's do we have?3210

We have our usual sp3 hybridized CH's, and how about this one?--that is now attached to an sp hybridized carbon CH, so we have an sp CH.3219

The sp3 occurs just below 3,000; and the sp--remember, the sp3 CH is just below 3,000, and then we have just above 3,000 as sp2, and then even further up, a higher number is sp.3235

This comes around 3,300.3252

OK, so those are all the CH's in our molecule: what other functional group do we have that we might find in the spectrum?3258

Well, we have this triple bond; and when that carbon-carbon triple bond stretches, that gives rise to an absorption; so we could just label that as a C-C triple bond; and that comes somewhere around 2,200.3264

OK, how about #3 here?--we have...let's start with the CH's again; let's start with the CH's.3281

We have our sp3 CH's right here; remember, we have to be able to interpret our line drawing to envision all of the significant bonds there.3288

So, we have sp3 CH just below 3,000; and how about this benzene ring--this aromatic ring?--what would we see?3300

We would see sp2 CH's just above 3,000; any other kinds of CH's that are unique?3311

Is this an sp2 CH, or is this something different?3321

No, this is actually an aldehyde; and an aldehyde CH is a unique type of hydrogen; and those are our little vampire fangs--that comes at around approximately 2,850 and 2,750; we get two peaks--two small peaks--when we have an aldehyde CH.3326

OK, so those are all the CH's; what other peaks might we find?3349

There is one that would be really obvious--that is the carbonyl: the carbonyl is always a significant peak.3354

Somewhere around 1,700 is where we find our carbonyl.3360

Those are going to be our most obvious peaks; anything else...well, remember, any time we have a benzene ring, you also might have carbon-carbon double bonds.3365

Those show up somewhere around 1,600; but those are variable intensity--sometimes we don't see them very easily.3375

Anything else?--what about the benzene ring--what about its substitution pattern?--how would you describe that benzene ring?3387

It has just one group attached, so we would call that a monosubstituted aromatic.3393

A monosubstituted aromatic, remember, has those out-of-plane bending motions that give rise to very strong peaks in the fingerprint region, and those come (let me just check my chart and see which numbers I gave you) somewhere around 750 and about 690.3401

Somewhere around 700 or 750, we expect two strong peaks for that monosubstituted.3422

OK, how about #4?--let's start with our CH's; do we have sp3 CH?--we do, right here--an sp3 CH just below 3,000 for our alkyl group--this ethyl group here.3429

And the aromatic ring has sp2 CH's; those come just above 3,000; those are all of our CH's.3445

We have a carbonyl again; that comes around 1,700; and the same thing we have up here--we have maybe the carbon-carbon double bond at around 1,600.3456

And we have our monosubstituted aromatic at around 750 and 690.3479

Plus, we will have that little aromatic ripple: that monosubstituted has a nice 1, 2, 3, 4-peak somewhere around 2,200; we can probably pick that out of the spectrum, as well.3486

OK, so it's about looking at a structure, now, and picking out what are the peaks--what are the functional groups that we know give rise to peaks when we put in an IR spectrometer and take a spectrum?3496

OK, let's look at four more.3512

How about our first spectrum here, compound 5: what functional groups?--we really don't have any functional groups--just a plain old alkane.3514

So, how would that look in the IR?3523

We would have sp3 CH's just below 3,000; and that is pretty much it.3526

I know we would have some of those C-H bends; those might be kind of a little more obvious, because the spectrum doesn't have much else going on; but it's nothing significant; it's not something we really have to pick out.3533

OK, so that would be a very simple IR spectrum.3546

How about 6--how about compound 6?3548

We have sp3 CH...what kinds of CH's do we have?--we have sp3 CH and sp2 CH; this is just below 3,000; this is just above 3,000.3553

And the obvious functional group here that is new is an OH; so we were getting that OH stretch for sure--that is a nice broad peak that we expect somewhere around 3,300.3574

We can make a little note here that it's going to be broad, as a reminder of what it will look like when we see that spectrum.3585

Anything else that is interesting?--well, we might find our carbon-carbon double bonds, and any time we have an oxygen in our structure, we could look for our C-O single bond (that is around 1,050).3593

All of these are approximate, of course; it depends on the exact structure.3610

So, around 1,600 for the double bonds...so somewhere around 1,050 for a C-O single bond; and then finally, we can have our monosubstituted aromatic; that is kind of the most commonly-encountered aromatic compound.3615

It is just a benzene ring with one substituent--so just a phenyl group.3630

That is a pattern that we might come across pretty frequently; again, that is about 750 and about 690...plus our little aromatic ripple.3635

So, a lot of stuff that is interesting in that spectrum, we can look for.3647

And how about #7--what kinds of hydrogens do we have here?3653

Once again, we have sp3 CH's and sp2 CH's.3657

It is always that cutoff just to the right; that is where we have our sp3s; just to the left is where we have our sp2s.3667

And we have a carbonyl; that is a big one that we can't miss--somewhere around 1,700, we expect to see a peak for a carbonyl (C, double bond, O) stretching.3677

And, of course, we have an OH; but what kind of OH is this?3693

It is not an ordinary alcohol; it is a carboxylic acid OH; so let's put that in our notes: carboxylic acid OH, because that means it goes from 3,500 down to 2,400--a huge, huge, huge, very broad signal that kind of obscures a lot of these C-H peaks.3697

And then, finally, we can come back to our monosubstituted aromatic; we can look for a carbon-carbon double bond, and we can look for our monosubstituted out-of-plane bending--that's what it's called; so 750 and 690.3719

OK, and finally, our last one here: what do we have?3741

A kind of boring structure: we just have carbons and hydrogens; so what do we see in the IR?3744

What is it we look for in the IR?--always, always, always the CH's are going to be incredibly important; so what kinds of CH's do we have here?3749

This part of the molecule has sp3 CH's, meaning tetrahedral carbons; that comes just below 3,000.3757

And this part of the molecule--the aromatic part--has sp2 CH's just above 3,000.3769

We can also, once again, look for our aromatic; our carbon-carbon double bonds might be somewhere around 1,600, and we can look for those two peaks at 750 and 690.3777

OK, so hopefully, after this lesson, you will have some comfort in looking at a structure and being able to predict what IR peaks you can expect.3793

If you flip through any textbook, at sample IR's you will see: it's a good idea to just start getting familiar with "here are some sample ketones," "some sample aldehydes," "some sample alcohols," so that you can confirm what these look like, because the next lesson is going to be: if you are given an IR spectrum with all of those wiggles and waggles, how can you come up with a structure--or more likely, match it to a set of structures that are given?3805

Because that is going to be the final test that we have in understanding IR spectroscopy.3829

I'll see you soon; thanks for coming to Educator.3838

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