Au(I)/Ag(I)-Catalyzed Cascade Approach for the Synthesis of Benzo[4,5]imidazo[1,2‑<i>c</i>]pyrrolo[1,2‑<i>a</i>]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.