Unusual ipso Substitution of Diaryliodonium Bromides Initiated by a Single‐Electron‐Transfer Oxidizing Process

Aromatic substitution: The treatment of diaryliodonium bromides 1 with aromatic nucleophiles 2, afforded a variety of heteroaryl-containing biaryls 3 in good yields. The ipso-substitution process at the heteroaryl ring in 1 occurs through the formation of aromatic cation radicals, which are initiated by the single-electron-transfer (SET) oxidation of 2. (HFIP= hexafluoroisopropanol)