Synthesis of Various New 2-Sulfonyl-Imine-Benzazoles via Heteroaryl C–H Activation Reactions of Benzo(thiazole-oxazole-imidazoles), Isocyanides, and Sulfinate Salts

A copper-catalyzed, one-pot, three-component C–H activation reaction of isocyanides, sulfinate salts, and benzothiazole, benzoxazole, or benzimidazole has been developed for the preparation a series of novel functionalized benzazoles bearing a sulfonyl-imine skeleton. This method provides an efficient route to form novel functionalized benzazole derivatives from simple and affordable starting materials under mild reaction conditions in moderate to good yields. Finally, by employing this method, 15 new compounds were synthesized and characterized simply, rapidly, and efficiently (76–92%).