Enantioselective oxidative gold catalysis enabled by a designed chiral P,N-bidentate ligand
Kegong Ji1, Zhitong Zheng, Zhixun Wang
1Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA (USA) http://www.chem.ucsb.edu/∼zhang/index.html; Current address: College of Science, Northwest A&F University, 3 Taicheng Road, Yangling 712100, Shaanxi (China).
Abstract:
A newly developed P,N-bidentate ligand enables enantioselective intramolecular cyclopropanation by a reactive α-oxo gold carbene intermediate generated in situ. The ligand design is based on our previously proposed structure (with a well-organized triscoordinated gold center) of the carbene intermediate in the presence of a P,N-bidentate ligand. A C2-symmetric piperidine ring was incorporated in the ligand as the nitrogen-containing moiety. A range of racemic transformations of α-oxo gold carbene intermediates have been developed recently, and this new class of chiral ligands could enable their modification for asymmetric synthesis, as demonstrated in this study.
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