(S)-5-prolylamide-triazole Organocatalyst for Direct Asymmetric Aldol Reactions

A new proline derivative of (S)-5-prolylamide-triazole was synthesized and evaluated as an organocatalyst for the direct asymmetric aldol reaction of acetone with aromatic aldehydes under no extra solvent. At room temperature and in the absence of extra solvent, 15 mol% catalyst efficiently catalyzed the direct asymmetric aldol reactions to give aldol adducts, with modest enantiomeric excess (ee) of up to 74%. The titled reactions can be carried out in an environmentally friendly manner of no extra solvent and less catalyst loading.