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Updated: Jul 25, 2026

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
An unexpected equilibrium process associated with a standard approach to ynone synthesis
Mary M Jackson1, Carolyn Leverett, Jennifer F Toczko
1GlaxoSmithKline, Chemical Development, Five Moore Drive, P.O. Box 13398, Research Triangle Park, North Carolina, 27709, USA.
Abstract:
A direct comparison between Weinreb amides and morpholine amides was made with regard to their reactions with alkynyllithium reagents to form ynones. While treatment with stoichiometric alkynyllithium generally effects complete reaction in the case of Weinreb amides, incomplete reactions are obtained from the corresponding morpholine amides. This difference is attributed to an unexpected equilibrium process in the latter case, and it is shown that the use of excess alkynyllithium reagent with morpholine amides provides a synthetically useful synthesis of ynones at 0 degrees C.
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