Tuning O2 Reactivity through Synergistic Photo/Copper Catalysis: Direct Synthesis of 4‐Aryl tetralones via Cyclodimerization–Oxygenation of Styrenes

Abstract A transformation is presented that enables chemists to construct 4‐aryl tetralones via visible‐light‐induced cyclodimerization–oxygenation of styrene under very mild conditions. Adding a catalytic amount of CuOAc obviously improves the yield. A mechanistic study reveals that the photoredox catalyst played the role of activating O 2 while Cu affected the reactivity of reactive oxygen species (ROS).