Highly Enantioselective Mukaiyama Aldol Reactions Catalyzed by a Chiral Oxazaborolidinium Ion: Total Synthesis of (−)-Inthomycin C

Abstract

A cationic oxazaborolidinium-catalyzed asymmetric Mukaiyama aldol reaction of (1-methoxy-2-methyl-propenyloxy)-trimethylsilane with various aldehydes including α,β-disubstituted acroleins has been developed in high yields and enantioselectivities. The synthetic utility of this methodology was demonstrated in the first short synthesis of naturally occurring inthomycin C in high enantiopurity.