Enantioselective Dearomative Cyclization Enabled by Asymmetric Cooperative Gold Catalysis
Ke Zhao1, Philip Kohnke1, Ziguang Yang1
1Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, USA.
Abstract:
A gold(I)-catalyzed enantioselective dearomatization is achieved via metal-chiral ligand cooperation. A new and divergent synthesis of chiral bifunctional binaphthyl-2-ylphosphines is developed to allow rapid access to these ligands, which in turn facilitate the application of this chemistry to a broad substrate scope including 1-naphthols, 2-naphthols, and phenols. Enantiomeric excesses up to 98 % are achieved via selective acceleration of one enantiomer formation enabled by hydrogen bonding between substrate and ligand remote basic group. DFT calculations lend support to the cooperative catalysis and substantiate the reaction stereochemical outcomes.
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