Gold(I)-Catalyzed Enantioselective Polycyclization Reactions

A series of enantioselective polycyclization reactions, catalyzed by a cationic bisphosphine gold complexes, are described. The polycyclization reactions, which employ an alkyne as an initiating group, begin with a gold-promoted 6-exo-dig cyclization and can be terminated with a variety of nucleophiles including carboxylic acids, phenols, sulfonamides, and electron-rich aryl groups. This method allows for the preparation of up to four bonds in a single operation with excellent diastereo- and enantioselectivity.