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Updated: Mar 21, 2026

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Toward vanadium-mediated alkyne metathesis
Shirley Hernandez1, Vasilisa Krivovicheva1, Adenilson Sousa-Silva2
1Department of Chemistry and Biochemistry, Florida International University Miami FL 33199 USA kbukhrya@fiu.edu.
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Alkyne metathesis, a widely used method for the synthesis of chemicals containing carbon-carbon triple bonds, relies exclusively on catalysts based on second and third-row transition metals. The development of a first-row metal-mediated alkyne metathesis would be a remarkable achievement from both fundamental and sustainability perspectives. In this study, we lay the groundwork for V-mediated alkyne metathesis. Thus, we demonstrated that V alkylidynes can react with various alkynes to produce cycloaddition products (metallacyclobutadienes), which are critical intermediates in the alkyne metathesis. Additionally, we conducted comprehensive computational studies to confirm the feasibility of the cycloreversion step needed to complete the alkyne metathesis transformation. Finally, we synthesized and characterized a series of new V alkylidynes, which can serve as essential starting materials for future development.
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