Asymmetric Aldol Reaction Of Isocyanoacetates With Aldehydes Catalyzed By Chiral Phase-transfer Catalysts

Isocyanoacetates are key building blocks in organic synthesis with widely applications in cyclization reactions.Recently,asymmetric synthesis with isocyanoacetates has emerged as one of the most powerful methods for the preparation of chiral heterocyclic compounds.Chiral oxazolines are core components present in many biologically and pharmaceutically active molecules.The aldol reaction of carbonyl compounds with isocyanoacetates provides an efficient method to access oxazolines and related derivatives.In this thesis,we developed a diastereo-and enantioselective aldol-type reaction of isocyanoacetates with aldehydes under metal-free phase-transfer catalytic conditions.This process proceeds smoothly in the presence of a catalytic amount of Cinchona alkaloid-derived quaternary ammonium salts,affording the corresponding chiral oxazoline products in high yields with diastereoselectivities up to 20:1 and enantioselectivities up to 78% ee.