Palladium-catalyzed syntheses of fused tricyclic heterocycles: A personal account

Fused tricyclic heterocycles are frequently found in pharmaceuticals, bioactive natural products and materials with unique molecular properties. The synthesis of these complex molecular scaffolds usually requires several reaction steps and harsh reaction conditions that may compromise the overall process yield. Therefore, the development of catalytic sequential reactions that enable the easy and efficient preparation of condensed tricyclic systems in a single reaction step is in high demand. In this account, we present recent advances in this direction based on the use of palladium-catalyzed cascade reactions developed in our laboratories.