Oxygen O(3 P) atom has been rarely explored in condensed-phase chemistry, with known examples limited to σ insertion into C − H bonds, alkene epoxidation, and sulfide oxidation. Herein, the authors report the efficient generation of oxygen O(3 P) atom via visible light-induced deoxygenation of aryl 1H benzotriazole 3-oxides under mild conditions and their transfer into the C−Cl bond of acyl chlorides to realize homolytic cleavage.