Direct remote Csp 2 –H transformation of aromatic amines enabled by organophotoredox catalysis

Despite the importance of difluoromethylene fragments in medicine, agrochemistry, and materials science, the precise and sustainable C–H difluoromethylation of aryl rings remains a challenge. Studies of metal-free difluoromethylation at room temperature would be advanced if methods were as reliable and modular as metal catalysis. Herein, we present a green and environmentally friendly modular platform for the sustainable para -difluoromethylation of readily available aromatic amines via a metal-free photocatalytic system. The reaction, for the first time, exhibits excellent functional group tolerance and broad substrate scope with a radical–radical coupling C–H functionalization strategy, rapidly delivering a variety of valuable difluoromethylated products. Furthermore, the derivatization of various complex molecules with high atom economy further demonstrates the synthetic utility and practicality of this protocol. A series of experimental studies and DFT calculations corroborate the plausible reaction mechanism.