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Updated: Jun 28, 2026

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Orthogonal reactivity in boryl-substituted organotrifluoroborates
Gary A Molander1, Deidre L Sandrock
1Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, USA. gmolandr@sas.upenn.edu
Abstract:
A method was developed for the hydroboration of alkenyl-containing organotrifluoroborates to generate dibora intermediates. The reactivity differences between organotrifluoroborates and trialkylboranes facilitated the cross-coupling of the borane moiety of these intermediates in a highly chemoselective fashion with aryl halides, leaving the trifluoroborate intact for subsequent transformation. A one-pot hydroboration/two-directional cross-coupling sequence was also demonstrated, providing the fully elaborated products in good yields. These conditions were also amenable in the cross-coupling of trialkylboranes to halo-containing organotrifluoroborates. The stability of the trifluoroborate moiety to these conditions allows simple and efficient strategies for complex molecule construction.
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