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Updated: May 23, 2026

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Synthesis of acyltrifluoroborates
Aaron M Dumas1, Jeffrey W Bode
1Laboratorium für Organische Chemie, Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology (ETH) Zürich, Wolfgang Pauli Strasse 10, 8093 Zurich, Switzerland.
Abstract:
Acylboranes are among the most elusive boron-containing organic functional groups, a fact that has impeded development of new reactions employing them as substrates. A new synthesis of acyltrifluoroborates from benzotriazole (Bt)-based N,O-acetals has been developed. Two other routes provide acyltrifluoroborates containing alcohols, aldehydes, and carbamates. The ketone-like reactivity of the acyltrifluoroborate functional group is demonstrated, and the first X-ray structure of an acyltrifluoroborate is reported.
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