Carboxylation of Aromatic and Aliphatic Bromides and Triflates with CO2 by Dual Visible‐Light–Nickel Catalysis

We report the efficient carboxylation of bromides and triflates with K₂CO₃ as the source of CO₂ in the presence of an organic photocatalyst in combination with a nickel complex under visible light irradiation at room temperature. The reaction is compatible with a variety of functional groups and has been successfully applied to the synthesis and derivatization of biologically active molecules. In particular, the carboxylation of unactivated cyclic alkyl bromides proceeded well with our protocol, thus extending the scope of this transformation. Spectroscopic and spectroelectrochemical investigations indicated the generation of a Ni⁰ species as a catalytic reactive intermediate.