Photoredox/Nickel-Catalyzed Decarboxylative Monofluoromethylation of β-Boryl NHPI Esters via Radical 1,2-Boron Migration.

A photoredox/nickel dual-catalyzed decarboxylative monofluoromethylation of β-boryl NHPI esters has been developed. The reaction proceeds through a radical 1,2-boron shift cascade, enabling the efficient conversion of β-boryl radicals into carbon radicals for subsequent SH2 cross-coupling with a monofluoromethyl radical. This method provides a mild and practical approach to access β-fluoromethylated boronic esters bearing versatile boronate functionalities. The transformation exhibits broad substrate scope and functional group tolerance, delivering congested quaternary carbon centers that are amenable to further synthetic elaboration.