Enantioselective synthesis of #beta#-hydroxy carboxylic acids: direct conversion of #beta#-oxocarboxylic acids to enantiomerically enriched #beta#-hydroxy carboxylic acids via neighboring group control

摘要

#beta#-Oxocarboxylic acids can be reduced to the corresponding #beta#-hydroxy carboxylic acids employing DIP-Cl~(TM) as a reducing agent. The #beta#-carboxylic substituent exerts a remarkable neighboring group effect on the reduction. The reaction presumably proceeds in an intramolecular fashion through a 'rigid' bicyclic transition state assembly, which produces enantioselectivities approaching 99%.