Copper-catalyzed aerobic photodecarboxylation of carboxylic acids to aldehydes and ketones

Base-metal-catalyzed decarboxylative transformations provide an economic pathway to the efficient functionalization of carboxylic acids. Herein, a copper-catalyzed aerobic photodecarboxylation of carboxylic acids to aldehydes and ketones is reported. The reaction operates through a ligand-to-metal charge transfer (LMCT) mechanism under light irradiation, with molecular oxygen serving as the oxidant. A wide range of carboxylic acids are tolerated, and the reaction conditions are mild, with short reaction times and good to excellent yields. Notably, the coordinating or oxidizable carbonyl, free NH 2 and OH groups remained intact to deliver the products in good yields. Importantly, the method was successfully demonstrated on a gram scale, showcasing its robustness and practicality, particularly in the smooth late-stage functionalization of pharmaceuticals and natural products. A visible-light-driven copper-catalyzed protocol for the aerobic decarboxylative transformation of carboxylic acids into structurally diverse aldehydes and ketones was reported. This photocatalytic system operates through a ligand-to-metal charge transfer (LMCT) activation mechanism, utilizing molecular oxygen as a green oxidant under mild reaction conditions.