Asymmetric cross- and self-aldol reactions of aldehydes in water with a polystyrene-supported triazolylproline organocatalyst

A polystyrene (PS) immobilized triazolylproline has been prepared by a bottom-up approach involving co-polymerization with full regiocontrol. The resulting PS resin swells in water and has been applied to the enantioselective cross-aldol reaction and to the self-aldol reaction of aldehydes under essentially neat conditions, excellent yields and stereoselectivities being recorded. A PS-immobilized triazolylproline prepared by co-polymerization with full regiocontrol swells in water and catalyzes the enantioselective cross-aldol reaction and the self-aldol reaction of aldehydes under essentially neat conditions with excellent stereocontrol.