Applications of Gold Catalysis for the Synthesis of Carbocycles

Abstract

Terpenoid natural products are important synthetic targets due to their abundance and broad range of physiological activity. Herein, we report a method taking advantage of the divergent nature of gold(I)-catalyzed cyclization reactions to reach a range of complex polycycles. Gold(I) complexes have been investigated to selectively modulate the regioselectivity of the cyclization reaction of a silyl enol ether onto a tethered alkyne. The resulting vinyl gold intermediates can then undergo a Prins-type cyclization or protodeauration. The diene generated from the 6-endo-dig cyclization/ protodeauration can react in a subsequent Diels-Alder reaction, forming tri and tetracyclic products. Overall, three efficient one-pot sequences were developed to selectively synthesize carbocycles from a common starting material. In addition, investigations into gold photoredox using dimeric catalyst [Au2[μ-dppm]2]X2 were also carried out for the synthesis of cyclic molecules.