Carbomethoxydifluoromethylation of enol acetates with methyl (chlorosulfonyl)difluoroacetate using visible-light photoredox catalysis. Synthesis of 2,2-difluoro-γ-ketoesters

•2,2-Difluoro-γ-ketoesters are prepared from enol acetates.•ClSO2CF2CO2Me is used as a source of MeO2CCF2 radicals.•Photoredox catalysis is used to carry out carbomethoxydifluoromethylation of enol acetates.

In a visible light, room temperature photoredox catalytic process using 0.5 mol% of a Ir[(dF(CF3)ppy)2(dtbbpy)]PF6 catalyst, a general method for attaching a carbomethoxydifluoromethyl group to the alpha position of a ketone, using the reaction of methyl (chlorosulfonyl)difluoroacetate (MCDA) with enol acetates, is reported. This method allows the synthesis of a variety of 2,2-difluoro-γ-ketoesters in moderate to very good yields.

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