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Updated: Aug 17, 2025

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Total Synthesis and Structure Confirmation of (E) and (Z)-Ocellenyne
Harry B Hicks1, Daniel S Brown1, Hau Sun Sam Chan1
1Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K.
Abstract:
The (E/Z)-ocellenynes are C15 dibrominated Laurencia natural products whose structures have been subject to several reassignments on the basis of extensive NMR analysis, biosynthetic postulates, and DFT calculations. Herein, we report the synthesis of both (E)- and (Z)-ocellenyne, which, in combination with single crystal X-ray diffraction studies, allows their absolute configuration to be established and defines the configuration of the syn-12,13-dibromide as being (S, S) in keeping with their proposed biogenesis from the (6S, 7S)-laurediols.
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