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Updated: Mar 2, 2026

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Rhenium(I)-Catalyzed Cyclopropanation of Alkenes with Vinylcarbenes Derived from Propargylic Ethers
FuJunyang Wu1, Yulin Che1, Junqi Chen1
1Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, P. R. China.
Abstract:
A rhenium-catalyzed method employing tetrahydropyran-substituted propargyl ethers as practical nondiazo carbene precursor for the efficient synthesis of vinylcyclopropanes (VCPs) is described. This method features a sequential 1,2-/1,5-hydride migration process to generate reactive vinyl rhenium carbenes, enabling subsequent cyclopropanation with a wide range of alkenes under user-friendly conditions. Notably, this operationally simple protocol features a broad substrate scope and provides a readily accessible starting material for assembling synthetically valuable VCPs. Furthermore, this method demonstrates significant potential in natural product synthesis.
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