Enantioselective organocatalytic Friedel-Crafts reaction of electron-rich phenols and isatins by Takemoto's thiourea catalyst

Abstract

Takemoto's catalysts were used to organocatalyze the enantioselective Friedel-Crafts reaction with different electron-rich phenols and substituted isatins. The resulting 3-aryl-3-hydroxyl-2-oxindoles were obtained in good yields (85-96%) with up to 99% ee. The substrate scope was broadened with this methodology compared to reported examples catalyzed by cinchonidine thiourea.

Keywords: Electron-rich phenols; Enantioselective; Friedel–Crafts reaction; Isatins; Takemoto’s catalyst.