CHEM 125B - Freshman Organic Chemistry II
Lecture 10 - Cation Intermediates - Alkenes: Formation, Addition, and Stability . Bridged pentavalent carbon structures can be intermediates or transition states of cation rearrangement during SN 1 reactions,
and short-lived ion pairs explain net stereochemical inversion. The different perspectives of preparative organic chemists and mechanistic organic chemists on reaction yields are illustrated by a study designed to demonstrate
that molecular rotation can be rate-limiting in viscous solvents. "Electrophilic" addition to alkenes is the reverse of E2 or E1 reaction, and its mechanisms can be studied by analogous techniques. The NIST Webbook provides
thermochemical data to help understand the relative stability of isomeric alkenes.
(from oyc.yale.edu
Lecture 10 - Cation Intermediates - Alkenes: Formation, Addition, and Stability
VIDEO
Time Lecture Chapters
[00:00:00]
1. Rearrangement of Cation Intermediates
[00:10:20]
2. Studying SN1 and E1 Mechanisms: Stereochemistry and Rate
[00:17:13]
3. Preparative and Mechanistic Perspectives on Competing Reactions
[00:20:51]
4. Preparing t-Butylhydrazine to Study Rate-Limiting Motion
[00:36:46]
5. "Electrophilic" Addition to Alkenes
[00:41:41]
6. NIST Webbook and the Stability of Isomeric Alkenes
Go to the Course Home
Lecture 01 - Mechanism: How Energies and Kinetic Order Influence Reaction Rates
Lecture 02 - Peculiar Rate Laws, Bond Dissociation Energies, and Relative Reactivities
Lecture 03 - Rate and Selectivity in Radical-Chain Reactions
Lecture 04 - Electronegativity, Bond Strength, Electrostatics, and Non-Bonded Interactions
Lecture 05 - Solvation, H-Bonding, and Ionophores
Lecture 06 - Bronsted Acidity and the Generality of Nucleophilic Substitution
Lecture 07 - Nucleophilic Substitution Tools - Stereochemistry, Rate Law, Substrate, Nucleophile, Leaving Group
Lecture 08 - Solvent, Leaving Group, Bridgehead Substitution, and Pentavalent Carbon
Lecture 09 - Pentavalent Carbon? E2, SN1, E1
Lecture 10 - Cation Intermediates - Alkenes: Formation, Addition, and Stability
Lecture 11 - Carbocations and the Mechanism of Electrophilic Addition to Alkenes and Alkynes
Lecture 12 - Nucleophilic Participation During Electrophilic Addition to Alkenes
Lecture 13 - Addition to Form Three-Membered Rings: Carbenoids and Epoxidation
Lecture 14 - Epoxide Opening, Dipolar Cycloaddition, and Ozonolysis
Lecture 15 - Metals and Catalysis in Alkene Oxidation, Hydrogenation, Metathesis, and Polymerization
Lecture 16 - Isoprenoids, Rubber, and Tuning Polymer Properties
Lecture 17 - Alkynes; Conjugation in Allylic Intermediates and Dienes
Lecture 18 - Linear and Cyclic Conjugation Theory; 4n+2 Aromaticity
Lecture 19 - Aromatic Transition States: Cycloaddition and Electrocyclic Reactions
Lecture 20 - Electronic and Vibrational Spectroscopy
Lecture 21 - Functional Groups and Fingerprints in IR Spectroscopy; Precession of Magnetic Nuclei
Lecture 22 - Medical MRI and Chemical NMR
Lecture 23 - Diamagnetic Anisotropy and Spin-Spin Splitting
Lecture 24 - Higher-Order Effects, Dynamics, and the NMR Time Scale
Lecture 25 - C-13 and 2D NMR - Electrophilic Aromatic Substitution
Lecture 26 - Aromatic Substitution in Synthesis: Friedel-Crafts and Moses Gomberg
Lecture 27 - Triphenylmethyl and an Introduction to Carbonyl Chemistry
Lecture 28 - Mechanism and Equilibrium of Carbonyl Reactions
Lecture 29 - Imines and Enamines; Oxidation and Reduction
Lecture 30 - Oxidation States and Mechanisms
Lecture 31 - Periodate Cleavage, Retrosynthesis, and Green Chemistry
Lecture 32 - Measuring Bond Energies: Guest Lecture by Prof. G. Barney Ellison
Lecture 33 - Green Chemistry; Acids and Acid Derivatives
Lecture 34 - Acids and Acid Derivatives
Lecture 35 - Acyl Insertions and alpha-Reactivity
Lecture 36 - alpha-Reactivity and Condensation Reactions
Lecture 37 - Proving the Configuration of Glucose and Synthesizing Two Unnatural Products
Lecture 38 - Review: Synthesis of Cortisone