One-Pot Synthesis of Indolo[2,1-b]quinazoline-6,12-diones under Aerobic Conditions

Abstract

An efficient approach for the formation of biologically important indolo[2,1-b]quinazoline-6,12-diones in good to moderate yields has been accomplished from 2-haloacetophenones and anthranilamides employing I2/DMSO/CuI under aerobic conditions. This tandem process is believed to proceed via iodination of 2-haloacetophenone followed by Kornblum oxidation and copper-catalyzed intramolecular N-arylation. This method adopts five reactions such as α-halogenation, oxidation, condensation, aromatization and heteroaryl coupling in a single step which makes it as an attractive and useful for the synthesis of indolo[2,1-b]quinazoline-6,12-diones.