Copper-Catalyzed Multicomponent Reactions (MCRs) for Disulfenylation of Imidazo[1,2-a]pyridines Using Elemental Sulfur and Arylhalides and Intramolecular Cyclization of Haloimidazo[1,2-a]pyridines.

摘要: Copper-catalyzed synthesis of disulfenylated imidazo [1, 2-a] pyridines and indoles using elemental sulfur and haloarenes through one-pot, three component reaction by two C–S–C bond formations has been developed. The method has a broad substrate scope with a variety of substituted haloarenes. The conditions were also applied for the synthesis of benzothieno-imidazo [1, 2-a] pyridines in excellent yields (99%) through intramolecular sulfenocyclization of 2-(2-halophenyl) imidazo [1, 2-a] pyridines using sulfur powder.