Protonated chiral (S)-prolinamide derivatives have been developed as water compatible highly efficient organocatalysts for a direct enantioselective aldol reaction. A simple protonated (S)-prolinamide organocatalyst prepared from l-proline and 3-nitroaniline catalyzes the aldol reaction of unmodified ketones and a variety of aromatic aldehydes yielding aldol product in high yield with enantioselectivities of up to 98% and ...
