Novel Chlorination of Imidazo‐Fused Heterocycles via Dichloro(aryl)‐λ3‐iodanes

Abstract A novel, safe, convenient and efficient protocol has been developed for regioselective chlorination of imidazo‐fused heterocycles with dichloro(4‐(trifluoromethyl)phenyl)‐λ 3 ‐iodanes under mild conditions. The present approach avoids the need of toxic chlorinating reagents, strong stoichiometric oxidants, metal catalysts or harsh reaction conditions. 36 examples of imidazo‐fused heterocycle substrates were investigated, and the chlorinated products were obtained with moderate to excellent yields. Control experiments indicated that the chlorinated reaction proceeded through an electrophilic aromatic substitution.