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Updated: Jun 24, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Base-catalyzed highly stereoselective conversion of gamma-hydroxy-alpha,beta-acetylenic esters to gamma-acetoxy
1Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, USA.
Abstract:
Gamma-hydroxy-alpha,beta-acetylenic esters can be conveniently prepared from the reaction of methyl propiolate with aldehydes in the presence of ZnEt(2) and N-methylimidazole at room temperature. It is discovered that the gamma-hydroxy-alpha,beta-acetylenic esters can be catalyzed by p-N,N-dimethylaminopyridine (DMAP) in acetic anhydride to generate the gamma-acetoxy dienoates with high stereo control. The mechanism of this conversion is investigated by NMR analyses and isotope labeling experiments. An intramolecular Diels-Alder reaction of a gamma-acetoxy dienoate is conducted to show the synthetic potential of these compounds.
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