Visible‐Light Photoredox‐Catalyzed Aminosulfonylation of Diaryliodonium Salts with Sulfur Dioxide and Hydrazines

A photoredox‐catalyzed three‐component synthesis of N ‐aminosulfonamides starting from diaryliodonium salts, hydrazines and sulfur dioxide is reported. This reaction proceeds under mild conditions at room temperature and is driven by visible light. A simple bisulfite salt can be used as a readily available and easy‐to‐handle sulfur dioxide source. Mechanistic studies support a catalytic photoredox pathway with the diaryliodonium salt as convenient source for aryl radicals.