Regioselectivity Control in the Oxidative Formal [3 + 2] Annulations of Ketoxime Acetates and Tetrohydroisoquinolines.

A novel copper-catalyzed oxidative formal [3 + 2] annulations of ketoxime acetates and tetrohydroisoquinolines for the synthesis of fused pyrazoles and imidazoles has been developed. A broad range of important isoquinoline-fused pyrazole and imidazole products were selectively generated by the key control of oxidant.