Catalyzed Reactions of Acyl Anion Equivalents

More than century after the description of the benzoin condensation, chemists are developing new approaches toward and new reactions involving aldehyde umpolung. This chemistry has been recently expressed in aldehyde/ketone benzoin condensations, aldehyde/imine couplings, and enantioselective benzoin (B) and Stetter (A) reactions (see scheme; M = K, Na, Bu4N; Y = S, NR; Z = CH, N; X=alkoxy, alkyl).