Enantioselective Total Synthesis of (+)-Peniciketals A and B: Two Architecturally Complex Spiroketals
Yifan Deng1, Chia-Ping H Yang2, Amos B Smith Iii1
1Department of Chemistry, University of Pennsylvania, 231 S. 34th Street, Philadelphia, Pennsylvania 19104, United States.
Abstract:
The enantioselective total syntheses of (+)-peniciketals A and B, two members of a family of architecturally complex spiroketals, have been achieved. Key synthetic transformations comprise Type I Anion Relay Chemistry (ARC) to construct the benzannulated [6,6]-spiroketal skeleton, a Negishi cross-coupling/olefin cross-metathesis reaction sequence to generate the trans-enone structure, and a late-stage large fragment union exploiting our recently developed photoisomerization/cyclization tactic.
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