Crystal structure of 6-bromo-7-fluoro-4-oxo-4H-chromene-3-carbaldehyde
1School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526 , Japan.
Abstract:
In the title compound, C10H4BrFO3, a brominated and fluorinated 3-formyl-chromone derivative, all atoms are essentially coplanar (r.m.s. deviation of 0.025 Å for the non-H atoms), with the largest deviation from the least-squares plane [0.050 (6) Å] being for a benzene-ring C atom. In the crystal, mol-ecules are linked through stacking inter-actions [centroid-centroid distance between the benzene and pyran rings = 3.912 (4) Å], C-H⋯O hydrogen bonds and short C⋯O contacts [2.865 (7) Å]. Unsymmetrical halogen⋯halogen inter-actions between the bromine and fluorine atoms [Br⋯F = 3.116 (4) Å, C-Br⋯F = 151.8 (2), C-F⋯Br = 154.1 (4)°] are also formed, giving a meandering two-dimensional network propagating in the (041) plane. A comparison with related structures is made and the various types of weak inter-actions are ranked in importance.
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