Merging Organocatalysis and Gold Catalysis: Enantioselective Synthesis of Tetracyclic Indole Derivatives through a Sequential Double Friedel–Crafts Type Reaction

摘要

Yet another indole miracle: The sequential combination of organocatalysis and gold catalysis on C2,C3-unsubstituted indoles provides an efficient one-pot access to tetracyclic indole derivatives in very good yields and excellent enantioselectivities (see scheme). The double Friedel–Crafts type reaction, including a rare 7-endo-dig cyclisation, opens a new entry to highly enantioenriched anticancer drugs, such as DNA intercalators.