Organocatalytic difluorobenzylation of 1,2-diketones via mild cleavage of carbon–carbon bonds

Abstract

α-Aryl-α,α-difluoroacetophenones (DFAPs) are developed as a new class of difluorobenzylation reagents that can be facilely prepared from readily available and cheap starting materials. In situ carbon–carbon bond cleavage of electron-deficient DFAPs gives difluorobenzyl carbanions that undergo base-catalyzed nucleophilic addition to isatins, unsaturated-α-ketoesters, and cyclic 1,2-diketones. This organocatalytic difluorobenzylation reaction provides a new and efficient protocol to prepare various valuable building blocks containing the electron-deficient difluorobenzyl group.