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Updated: Apr 14, 2026

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Ring-closing enyne metathesis of terminal alkynes with propargylic hindrance
Benjamin Laroche1, Morgane Detraz1, Alain Blond1
1†Unité Molécules de Communication et Adaptation des Micro-organismes, Sorbonne Universités, Muséum National d'Histoire Naturelle, Centre National de la Recherche Scientifique (CNRS UMR 7245), 57 rue Cuvier (CP 54), 75005 Paris, France.
Abstract:
The ring closing enyne metathesis of substrates with propargylic hindrance was investigated, revealing the successful combination of the Stewart-Grubbs catalysts and microwave heating sometimes up to 170 °C for oxacycles. Medium-sized rings were obtained from terminal alkynes previously reputed as reluctant substrates. This unmatched combination was applied to the synthesis of carbocycles and oxacycles. In addition, this is the first report on the use of the Stewart Grubbs catalyst in ring closing enyne metatheses.
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