UC Santa Barbara

Asymmetric gold(I) catalysis has remained challenging over the past two decades, largely due to the linear coordination of gold(I) complexes. Over the last ten years, the Zhang group has made significant progress in addressing this challenge by developing bifunctional phosphine ligands and pioneering their applications in ligand-enabled cooperative homogeneous gold catalysis. During my graduate study, I focused on further applications of these designed ligands in cooperative gold catalysis and in particular asymmetric ones. The first part of this dissertation discusses a highly enantioselective trapping of an oxidatively generated gold carbene by an alcoholic nucleophile. With an amide-functionalized chiral binaphthylphosphine ligand, γ-alkoxy-α,β-unsaturated imides were formed with excellent enantiomeric excesses. The second part discusses gold-catalyzed dimerization of terminal alkynes, in which we observed for the first time a 3′-diisopropylphosphoryl group of a ligand promoting the terminal alkyne attack. The last part covers enantioselective gold-catalyzed enyne cycloisomerizations. These reactions employ chiral bifunctional ligands to induce product chirality in a non-cooperative manner, in which the ligand does not directly participate in the bond-forming or bond-breaking processes during the reaction.