Freshman Organic Chemistry II (CHEM 125B)
Preliminary X-ray analysis of molecules that have been designed to favor a carbon with five bonds seemed to suggest the possibility of a pentavalent intermediate in SN2 reactions, but further analysis of these structures showed just the opposite. Boron, however, can be pentavalent in such an environment. E2, SN1 and E1 mechanisms compete with the SN2 reaction. Factors controlling E2 eliminations are illuminated by kinetic isotope effects, stereochemistry, and regiochemistry. The competition between E2 and SN2 mechanisms influence the design of synthetic schemes, including those in which carbon nucleophiles play an important role. SN1 and E1 reactions involve carbocation intermediates and thus the possibility that the carbon skeleton will rearrange.
00:00 - Chapter 1. Using X-Ray to Investigate the Possibility of a Pentavalent Carbon Intermediate
14:41 - Chapter 2. The E2 Reaction and Kinetic Isotope Effects
19:51 - Chapter 3. Stereochemistry & Regiochemistry of E2 Elimination
32:20 - Chapter 4. Strategies for Substitution in Organic Synthesis
41:39 - Chapter 5. SN1 and E1 Reactions - Kinetic Evidence for SN1 Substitution
45:09 - Chapter 6. Carbocation Intermediates: Competition and Rearrangement
Complete course materials are available at the Open Yale Courses website: http://oyc.yale.edu
This course was recorded in Spring 2011.
Tagged under: pentavalent carbon,SN2,kinetic isotope effect,E2,anti-elimination,Saytzeff rule,Hofmann rule,Williamson ether synthesis,epoxide,oxirane,SN1,E1,carbon nucleophile,cation rearrangement
Clip makes it super easy to turn any public video into a formative assessment activity in your classroom.
Add multiple choice quizzes, questions and browse hundreds of approved, video lesson ideas for Clip
Make YouTube one of your teaching aids - Works perfectly with lesson micro-teaching plans
1. Students enter a simple code
2. You play the video
3. The students comment
4. You review and reflect
* Whiteboard required for teacher-paced activities
With four apps, each designed around existing classroom activities, Spiral gives you the power to do formative assessment with anything you teach.
Carry out a quickfire formative assessment to see what the whole class is thinking
Create interactive presentations to spark creativity in class
Student teams can create and share collaborative presentations from linked devices
Turn any public video into a live chat with questions and quizzes