Enantioselective Direct Aldol Reactions Using Bifunctional Catalysis

Significance

Enamine catalysis has emerged as an extremely useful method for performing ‘direct’ aldol reactions (see Review below). Most of these catalysts contain secondary amines, and examples of highly enantioselective direct aldol reactions involving primary amines are rare. The authors have designed new chiral catalysts based on amino acids which utilize a primary amine as the Lewis basic site and a tightly bound metal as the Lewis acid site. These catalysts give high dia­stereo- and enantioselectivity in the direct aldol ­reaction of ketones with benzaldehydes.