Gold(I)-Catalyzed Tandem Synthesis of Polycyclic Dihydroquinazolinones

A gold-catalyzed cascade process for the synthesis of dihydroquinazolinone scaffolds was developed. A series of gold catalysts were screened for this tandem transformation, and the (PPh3)AuCl/AgOTf catalyst combination was found to be the best catalyst system. This method is characterized by good yields, high regioselectivity, and broad substrate scope. This method is also applicable to the synthesis of tetracyclic dihydroquinazolinones and seven-membered ring-fused dihydroquinazolinones.