Studies On The Asymmetric Thia-Mannich Reaction Catalyzed By Chiral Bronsted Acids

This thesis is composed of three parts:(1) Brφnsted acid catalyses are rapidly growing areas in organocatalysis. In this part, the development of the Brφnsted acid catalyzed asymmetric reactions is illustrated from its very beginning up to the present. The progress on the chiral Bronsted acid catalysis has been reviewed with a focus being placed on addition reaction, cyclization reaction, and counteranion directed catalysis.(2) We have developed the asymmetric addition reactions of thiophenol to N-acyl imines. The addition products were obtained in high yields (up to 98%) and excellent enantioselectivities (up to 99%) under the optimized reactions conditions. The method is applicable to not only simplifys experimental condition, but also enables facile access to highly enantioenriched chiral N-acetal derivatives.(3) We investigated asymmetric Friedel-Crafts alkylation reaction of P-naphthol. Although, the Friedel-Crafts products could be prepared in a straightforward procedure in high yields under mild reaction conditions, enantiomeric excess is poor.