Au(I)/Ag(I)-catalyzed cascade approach for the synthesis of benzo[4,5]imidazo[1,2-c]pyrrolo[1,2-a]quinazolinones.

An efficient and facile Au(I)/Ag(I)-catalyzed cascade method has been developed for one-pot synthesis of the complex polycyclic heterocycles benzo[4,5]imidazo[1,2-c]pyrrolo[1,2-a]quinazolinone derivatives through treatment of the substituted 2-(1H-benzo[d]imidazol-2-yl)anilines with 4-pentynoic acid or 5-hexynoic acid. The strategy features a Au(I)/Ag(I)-catalyzed one-pot cascade process involving the formation of three new C-N bonds in high yields, and with broad a substrate scope.