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Updated: Jan 13, 2026

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
FeCl3-Catalyzed Synthesis of Ynones from Silylated Alkynes and Acetic Anhydride
Paul Charki1, Urs Gellrich2, Daniel S Müller1
1CNRS, Institut des Sciences Chimiques de Rennes-UMR6226, Univ Rennes, F-35000, Rennes, France.
Abstract:
The reaction of silylated alkynes with acid chlorides in the presence of Lewis acids, first described by Birkhofer in 1963, has since emerged as a valuable method for the synthesis of alkynones. Despite its broad synthetic utility, the original protocol suffers from notable drawbacks, including the use of toxic solvents, stoichiometric Lewis acids, and corrosive acylating agents. In light of growing environmental concerns, a more sustainable alternative is developed. Herein, catalytic amounts of iron(III) chloride in combination with biodegradable acetic anhydride enable the efficient synthesis of alkynones under mild conditions.
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