Asymmetric α-electrophilic difluoromethylation of β-keto esters by phase transfer catalysis

Org Biomol Chem. 2021 Jun 2;19(21):4788-4795. doi: 10.1039/d1ob00511a.

Abstract

An efficient and enantioselective α-electrophilic difluoromethylation of β-keto esters has been achieved by phase-transfer catalysis. This procedure is applicable to different kinds of β-keto esters with a series of cinchona-derived C-2' aryl-substituted phase-transfer catalysts. The reaction gives the corresponding products in good enantioselectivities (up to 83% ee) and yields (up to 92%) with high C/O regioselectivities (up to 98 : 2). Moreover, the C/O selectivity of β-keto esters could be easily reversed and controlled. This asymmetric difluoromethylation provided a novel and efficient way for introducing chiral C-CF2H groups.

Publication types

  • Research Support, Non-U.S. Gov't