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Updated: Mar 14, 2026

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Strategies for the Total Synthesis of Diverse Bromo-Chamigrenes
Minxing Shen1,2, Manuel Kretschmer3, Zachary G Brill3
1Dept. of Chemistry, The University of Chicago , 5735 South Ellis Avenue, Chicago, Illinois 60637, United States.
Abstract:
Several dozen spirocyclic sesquiterpenoids known as the bromo-chamigrenes have been isolated to date. Yet, despite their unique structures, synthetic efforts toward this collection have been modest. Herein, we outline two strategies to generate their skeletons based on (1) a biomimetic bromonium-induced polyene cyclization using BDSB (Et2SBr·SbCl5Br) and (2) a Diels-Alder reaction which ultimately delivered four members of the class. In addition, X-ray crystallography reveals that one member has a structure in need of revision.
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