Organo-catalyzed highly diastereo- and enantio-selective direct aldol reactions in water

The asymmetric direct aldol reactions of a wide scope of aromatic aldehydes, with unmodified ketones in the presence of 1 mol % of organocatalyst prepared from (2R,3R)-diethyl 2-amino-3-hydroxysuccinate and trans-4-hydroxy-l-proline, were performed in water, affording aldol products in high yields with excellent diastereoselectivities of up to >99:1 and enantioselectivities of up to 98%.