Synthesis of 2,1-Benzoisoxazole-Containing 1,2,3-Triazoles through Copper-Catalyzed Three-Component Domino Reactions of o-Bromoacetophenones, Aldehydes, and Sodium Azide.

We herein describe an efficient copper-catalyzed three-component domino protocol used to prepare 2,1-benzoisoxazole-containing 1,2,3-triazoles from commercially available o-bromoacetophenones, aldehydes, and sodium azide. This domino process involves Aldol condensation, copper-catalyzed azide-chalcone oxidative cyclization, 1,2,3-triazole-assisted azidation, and denitrogenative cyclization sequences. The formed compounds could be considered as benzo[c]isoxazole-functionalized combretastatin A-4 triazole analogues, which might be potential applications in the discovery of a new anticarcinogen.