Cheng‐Liang Liu, Jia Liu, Jia‐Ying Dai, Zi‐Rui Kuang, Zhixing Liu, Qian Yan, Zhiwei Li, Jiang‐Sheng Li
A dual‐catalytic metallaphotoredox strategy repurposes sulfonamides as sulfonylating reagents via radical cascades, leveraging copper's dual role as photoredox mediator and coupling catalyst. Exemplified by iodosulfonylation of alkynes, the protocol achieves in situ sulfonamide diazotization to generate sulfonyl radicals, followed by regioselective addition to alkynes and copper‐catalyzed iodination. This all‐in‐one strategy eliminates the need for sulfonamide prefunctionalization, offering step‐economy, operational simplicity, and broad functional group tolerance.