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Updated: Mar 1, 2026

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Access to Tetronic Acids via Silver-Catalyzed CO2 Incorporation into Conjugated Ynones
Yuta Sadamitsu1, Keiichi Komatsuki1, Kodai Saito1
1Department of Chemistry, Keio University , 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
Abstract:
Facile and versatile access to highly functionalized tetronic acids has been successfully achieved through the reaction of conjugated ynones with carbon dioxide. In the presence of a base, the enolates generated from the ynones capture CO2 via a carbon-carbon bond-forming reaction, accompanied by a 5-exo-dig cyclization reaction of the resulting carboxylate to the alkyne, activated by a silver catalyst. The present method should be applicable to the synthesis of a wide variety of tetronic acids.
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