Abstract Proline-based organocatalysts have been developed for a highly enantioselective, direct aldol reaction of aldehydes and ketones in the presence of water. While several surfactant–proline combined catalysts have proved effective, proline derivatives with a hydrophobic moiety such as trans-siloxy-L-proline and cis-siloxy-D-proline, both of which are easily prepared from the same commercially available 4-hydroxy-L-proline, have been ...
