Asymmetric aldol reactions in ketone/ketone systems catalyzed by ionic liquid-supported C2-symmetrical organocatalyst

Abstract

Ionic liquid-supported (1S,2S)- and (1R,2R)-1,2-bis[(S)-prolinamido]-1,2-diphenylethanes act as organocatalysts in asymmetric aldol reactions of acetone with α-keto esters or trifluoroacetophenone providing high yields and from moderate to high enantioselectivity. Recycling of the catalyst with a gradual decrease in conversion and ee values is possible.