I. MECHANISTIC ASPECTS OF PHASE-TRANSFER CATALYSIS. II. ASYMMETRIC INDUCTION IN PI SYSTEMS ADJACENT TO CHIRAL CENTERS (BENZYL CHLORIDE).

摘要

The reaction of benzyl chloride and benzyl bromide with KCN, KN(,3), KOAC and KSCN under conditions of liquid-liquid and solid-liquid phase transfer catalysis was studied. The phase transfer reagents included 18-crown-6, dicyclohexyl-18-crown-6, tetrabutylammonium chloride and bromide. During the study, the following conditions were varied: concentrations of the catalysts and reactants, amount of water, and the temperature. The results of this study were analyzed and a new model for the mechanism of phase transfer catalysis was developed.;The reaction of a nucleophile attacking a carbonyl that is adjacent to a chiral center was studied. The two main variables in this study were the varying of the nucleophile and the varying of the achiral group adjacent to the carbonyl. The ratio of the diastereomers were determined and these ratios were in turn related to calculated trajectories that a nucleophile would follow in these systems.