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Updated: Sep 20, 2026

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Regiochemical variation in the electrophilic addition of HBr to 1-phenylprop-1-yne
Hilton M Weiss1, Kim M Touchette, Frantz Andersen
1Department of Chemistry, Bard College, Annandale-on-Hudson, New York 12504, USA.
Abstract:
The reaction of aryl alkynes with dilute methylene chloride solutions of quaternary ammonium bromide and 20% trifluoroacetic acid produces primarily the syn Markovnikov adducts of hydrogen bromide. At moderate concentrations of the bromide, the principal product is the Markovnikov anti adduct. At high concentrations of bromide, the anti-Markovnikov anti addition product predominates.
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