SUPRAMOLECULAR ARCHITECTURE IN THE CRYSTALS OF POLYFLUORINATED HOMOPHTHALIC ACIDS
Т. V. Rybalova, Y. V. Gatilov, Y. V. Zonov, V. ??. Karpov
Keywords: polyfluorinated 2-(carboxymethyl)benzoic (homophthalic acids), crystal structure, hydrogen bonding, C-F…ПЂ and Н-O…ПЂ interactions, supramolecular synthon
Pages: 769-774
Abstract
X-ray diffraction analysis of four perfluorinated homophthalic (2-carboxymethylbenzoic) acids is carried out. In the crystals of 2-carboxymethyl-3,4,5,6-tetrafluorobenzoic acid (1) the chains (1D architecture) form with the usual dimeric carboxylic C(O)OH:::O(HO)C synthon. The aromatic carboxylic group is disordered in the ratio 0.58:0.42 over two positions. In the crystals of 2-(carboxydifluoromethyl)-3,4,5,6-tetrafluorobenzoic (2) and 2-(1-carboxy-2,2,2-trifluoroethyl)-3,4,5,6-tetrafluorobenzoic acids (3) the layers (2D architecture) with dimeric and chain-like synthons C(O)OH…O(HO)C are found. In the crystals of 2-[methoxycarbonyl(difluoromethyl)]-3,4,5,6-tetrafluorobenzoic acid (4) only dimers (0D architecture) form with the chain synthon that incorporates both an ester and a carboxylic group. In the crystals of 1 and 2 intermolecular Н-O…π interactions, in the crystals of 4 C-F…π interactions, and in 3 both types of interactions are observed.
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