Gold-Catalyzed Synthesis of Chiral Cyclopentadienyl Esters via Chirality Transfer
Ke Zhao1, Yu-Chen Hsu1,2, Ziguang Yang1
1Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States.
Abstract:
Efficient access to chiral cyclopentadienyl esters from readily accessible chiral enynyl ester substrates is developed. Typically high levels of chirality transfer realized in this homogeneous gold catalysis are attributed to the intermediacy of a chiral bent allene gold complex. Cyclopentadienyl esters can be prepared in good yields and with excellent enantiomeric excesses. The synthetic utilities of the chiral cyclopentadienyl esters are demonstrated by the Diels-Alder reactions, fluorination, alkylation, and epoxidation without any notable erosion of enantiopurity.
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