Novel Prolinamide Organocatalysts Based on Calix[4]arene Scaffold for the Enantioselective Direct Aldol Reaction

A series of novel prolinamide organocatalysts based on calix[4]arene scaffold have been developed to catalyze the direct asymmetric aldol reaction of aromatic aldehydes and cyclohexanone. Under the optimal condition, high isolated yields (up to > 99%) and enantioselectivities (up to 97% ee), and moderate diastereoselectivities (up to 85/15) were obtained.