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Updated: Jun 1, 2026

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
2-Bromo-3-phenyl-1-(3-phenyl-sydnon-4-yl)prop-2-en-1-one
Abstract:
THE TITLE SYDNONE DERIVATIVE [SYSTEMATIC NAME: 2-bromo-1-(5-oxido-3-phenyl-1,2,3-oxadiazo-lium-4-yl)-3-phenyl-prop-2-en-1-one], C(17)H(11)BrN(2)O(3), exists in a Z configuration with respect to the acyclic C=C bond. An intra-molecular C-H⋯Br hydrogen bond generates a six-membered ring, producing an S(6) ring motif. The 1,2,3-oxadiazole ring in the sydnone unit is essentially planar [maximum deviation = 0.011 (2) Å] and forms dihedral angles of 55.39 (13) and 57.12 (12)° with the two benzene rings. In the crystal structure, inter-molecular C-H⋯O hydrogen bonds link mol-ecules into two-mol-ecule-thick arrays parallel to the bc plane. The crystal structure also features a short inter-molecular N⋯C contacts [3.030 (3) Å] as well as C-H⋯π and π-π inter-actions [centroid-centroid distances = 3.3798 (11) and 3.2403 (12) Å].
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