Simple Primary Amino Amide Organocatalyst for Enantioselective Aldol Reactions of Isatins with Ketones

Enantioselective aldol reactions of various isatins with ketones using newly designed amino amide organocatalysts were found to provide chiral 3-substituted 3-hydroxy-2-oxindoles in good to excellent yields and with excellent stereoselectivities (up to 99 %, up to 98 % ee, syn/anti = 99:1); one catalyst, 3i, proved particularly successful. One of the resulting oxindoles, 3-hydroxy-3-(2-oxocyclohexyl)-2-indolinone may serve as a synthetic intermediate for pharmaceutically important compounds and, in its own right, shows interesting anticonvulsant activities.