CHEM 222 Chapter Notes - Chapter 6: Retrosynthetic Analysis, Sn2 Reaction, Rate-Determining Step

• School: McGill University
• Department: Chemistry
• Course: CHEM 222
• Professor: Laura Pavelka

Document Summary

Stereochemistry: sn2 always occurs with inversion of configuration at atom bearing lg, can figure out configuration product if know that of reactant. 6. 15 elimination reactions of alkyl halides: compete with substitution reactions, fragments of some molecule (yz) removed from adjacent atoms of reactant, leads to formation multiple bond. Mechanism dehydrohalogenation: variety mechanism: e2 reaction bimolecular; e1 reaction unimolecular for rate- determining step. 6. 16 e2 reaction: orientations of h atoms removed and lg oriented in same plane, similar geometry to sn2: electron pair of c-h bond pushes lg away from the opposite side as base removes the h. 6. 17 e1 reaction: first order kinetics, initial step = formation tert-butyl cation as intermediate (slow, e1 almost always accompany sn1 reactions, whether substitution or elimination takes place depends on second step (fast) If solvent reacts as nucleophile at + c atom of tert-butyl tert-butyl alcohol or tert- butyl ethyl ether. If solvent acts as base and removes a beta.