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5 citations found for Silva, M.S.
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In the title compound, C17H16O6, the two methyl salicylate moieties are related by crystallographic twofold rotational symmetry with the two benzene rings close to being perpendicular [inter-ring dihedral angle = 86.6 (8)°]. Intramolecular phenolic O—H
O hydrogen bonds with carboxyl O-atom acceptors are present, with these groups also involved in centrosymmetric cyclic intermolecular O—HO hydrogen-bonding associations [graph set R22(4)], giving infinite chains extending across (101).
O hydrogen bonds with carboxyl O-atom acceptors are present, with these groups also involved in centrosymmetric cyclic intermolecular O—HO hydrogen-bonding associations [graph set R22(4)], giving infinite chains extending across (101).organic compoundsOpen access
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The title compound, C15H22N2O3, was obtained as a by-product of oxidative cleavage of 1,3-dicyclohexyl-(3-oxo-2,3-dihydrobenzofuran-2-yl)imidazolidine-2,4-dione. Herein, we report the crystal structure of a second polymorph, which was obtained by crystallization from an ethanol solution at 253 K, instead of slow evaporation of the same solvent at room temperature. While the first polymorph [Talhi et al. (2011). Acta Cryst. E67, o3243] crystallized in the non-centrosymmetric space group P212121, this second polymorph crystallizes in the centrosymmetric space group P21/n. Compared to the first polymorph, in the crystal no C=OC=O interactions were found (CO intermolecular distance longer than 3.15 Å) and instead, close packing of individual molecular units is mediated by C—Hπ and weak C—HO interactions.
C=O interactions were found (CO intermolecular distance longer than 3.15 Å) and instead, close packing of individual molecular units is mediated by C—Hπ and weak C—HO interactions.organic compoundsOpen access
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The title compound, C15H22N2O3, has been isolated as a by-product of an oxidative cleavage of the C—C bond linking two five-membered rings of 1,3-dicyclohexyl-5-(3-oxo-2,3-dihydrobenzofuran-2-yl)imidazolidine-2,4-dione. Individual molecular units are engaged in weak C=OC=O interactions [OC = 2.814 (10) and 2.871 (11) Å], leading to the formation of supramolecular chains which close pack, mediated by van der Waals contacts, in the bc plane.
C=O interactions [OC = 2.814 (10) and 2.871 (11) Å], leading to the formation of supramolecular chains which close pack, mediated by van der Waals contacts, in the bc plane.
research papers
In a crystal structure based on ∞1[Ca2(H2cpp)2(H2O)2] ladders [H2cpp is (4,5-dicyano-1,2-phenylene)bis(phosphonate)], the ladders close pack in the solid state with water molecules mediated by various hydrogen-bonding interactions.
