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.