Figure 1. Carboxylic acids as coupling partners in a metallaphotoredox-mediated process to form sp³–sp³ bonds.

The majority of transition metal-catalyzed cross-couplings generally employ at least one sp^2-hydridized coupling partner. The direct utilization of robust, widely available, native functional groups such as carboxylic acids should encourage greater adoption of sp³–sp³ bond forming methods.