Photocatalytic acyl azolium-promoted alkoxycarbonylation of trifluoroborates.

Despite recent advancements in the selective generation and coupling of organic radical species, the alkoxycarbonyl radical remains underexplored relative to other carbon-containing radical species. Drawing inspiration from new strategies for generating acyl radical equivalents utilizing dual N-heterocyclic carbene catalysis and photocatalysis, we have prepared dimethylimidazolium esters that can function as an alkoxycarbonyl radical surrogate under photocatalytic conditions. We demonstrate the synthetic utility of these azolium-based partners through the preparation of esters arising from the coupling of this radical surrogate with an oxidatively generated alkyl radical.