Gold-Catalyzed Arylative and Alkenylative Semipinacol Rearrangements: Reaction Development, Mechanistic Insights, and Enantioselective Variant

Herein, we report the ligand-enabled gold-catalyzed arylative and alkenylative semipinacol rearrangements of allylic alkanols employing aryl and vinyl iodides as coupling partners. Furthermore, we developed an asymmetric variant of the reaction through enantioselective gold redox catalysis enabled by the chiral ChetPhos ligands. Leveraging the Au(I)/Au(III) catalysis with the intrinsic carbophilic activation characteristic of gold, the reaction is shown to work with unactivated alkenes, eliminating the need for activated alkenes as reported previously. Combined experimental and computational studies highlighted the role of the axially chiral C2-symmetric dihydroazepino-binaphthyl unit of the (P,N)-ligand (ChetPhos) in achieving high enantioselectivity.