An Effective Synthesis of Indazolo2,1-aindazole-6,12-diones by Regioselective Copper-Catalyzed Cascade Acylation/Coupling Cyclization Process

摘要

A new and efficient cascade synthesis of indazolo[2,1-a]indazole-6,12-diones has been developed. This protocol includes an intermolecular N-acylation followed by a copper-catalyzed intramolecular C--N coupling reaction. The methodology is applied to a wide range of 2-bromo and 2-chloro benzoyl chlorides to yield the indazolo- [2,1-a]indazole-6,l 2-diones in good to excellent yields with high regioselectivities.