Total Synthesis of Cyanolide A in the Absence of Protecting Groups, Chiral Auxiliaries, or Premetalated Carbon Nucleophiles

Authors

  • Andrew R. Waldeck,

    1. University of Texas at Austin, Department of Chemistry and Biochemistry, 1 University Station—A5300, Austin, TX 78712-1167 (USA)
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  • Prof. Michael J. Krische

    Corresponding author
    1. University of Texas at Austin, Department of Chemistry and Biochemistry, 1 University Station—A5300, Austin, TX 78712-1167 (USA)
    • University of Texas at Austin, Department of Chemistry and Biochemistry, 1 University Station—A5300, Austin, TX 78712-1167 (USA)===

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  • Acknowledgements are made to the Robert A. Welch Foundation (F-0038) and the NIH-NIGMS (RO1-GM093905) for partial financial support. Dr. Abbas Hassan and Dr. Anne-Marie Dechert-Schmitt are gratefully acknowledged for technical assistance.

Abstract

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No protection, no problem: The C2-symmetric macrodiolide cyanolide A is prepared in six steps from neopentyl glycol and allyl acetate by iridium-catalyzed double asymmetric allylation and a tandem cross-metathesis/oxa-Michael cyclization to form the substituted pyran. The synthesis is accomplished in the absence of any protecting groups, chiral auxiliaries, or premetalated carbon nucleophiles in fewer than half the steps of any prior approach.

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