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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Asymmetric synthesis of the oxygenated polycyclic system of (+)-harringtonolide
Hajer Abdelkafi1, Patrick Herson, Bastien Nay
1Muséum National d'Histoire Naturelle, Molécules de Communication et Adaptation des Micro-organismes (UMR 7245 CNRS-MNHN), 57 rue Cuvier (CP 54), 75005 Paris, France.
Abstract:
A straightforward asymmetric synthesis of the cage oxygenated structure of (+)-harringtonolide has been accomplished for the first time. The key steps involved (i) a templated stereoselective IMDA reaction to build a highly functionalized cyclohexene ring D, (ii) functionalization of the cycloadduct, (iii) ring-closing metathesis providing the five-membered ring C, and finally (iv) a challenging one-step cascade cyclization of an epoxy-alcohol toward the target structure, whose mechanism was investigated.
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