Single-crystals of hexafluoridouranium(VI), UF6, were obtained by sublimation. A re-refinement of the crystal structure using low-temperature (100 K) single-crystal X-ray data was carried out considering all Uij terms of the displacement parameters of the U and F atoms, leading overall to a significantly improved structural model. UF6 crystallizes in the orthorhombic space group Pnma with the F atoms forming a double hexagonal closest packing of ABAC stacking with U atoms in one-sixth of the voids. The UF6 molecules deviate only slightly from octahedral point-group symmetry.
The tricyclic molecule of the title compound, C12H14O2, is composed of four nearly planar subunits. Hydrogen bonds connect the ketol units to chains along the a-axis direction. The structure is further consolidated by two C—H...O hydrogen bonds, one to the carbonyl and one to the hydroxy group.
The title compound, C 15 H 10 Cl 2 N 2 , was synthesized using the acid catalyst NH 4 HF 2 in a water/methanol solution. The dihedral angle between the phenyl ring and the quinoxaline unit is 39.80 (5)°. There is an intermolecular hydrogen-bonding-like interaction with a neighboring chlorine atom at a distance of 2.76 Å. The extended structure features offset-stacked quinoxaline units along the [100] direction.
The title compound, C 16 H 11 BrN 2 , is a Schiff base formed through the condensation reaction of 2-quinolinecarboxaldehyde with 4-bromoaniline. The C=N bond length of 1.282 (2) Å is consistent with its double-bond character. The imine linkage adopts the E configuration, as indicated by the N—C—C—N torsion angle of 174.27 (14)°. This value also demonstrates that the quinoline ring and imine group are arranged in an almost coplanar manner. In contrast, the 4-bromophenyl ring is significantly twisted relative to the imine-quinoline plane, as indicated by the C—N—C—C torsion angle of approximately 46.8 (2)°. Intermolecular C—H...π interactions between quinolinyl and bromophenyl rings form a three-dimensional supramolecular network in the crystal packing.
The title complex, [RuCl 2 (C 6 H 6 )(C 21 H 33 P)] or (η 6 -C 6 H 6 )((C 6 H 11 ) 2 ( i PrC 6 H 4 )P)RuCl 2 crystallizes in the space group P 1 with one molecule in the asymmetric unit. The Ru II atom is located at distances of 2.3830 (7), 2.3925 (8), 2.4269 (8), and 1.6919 (3) Å from the P, the two Cl ligands, and the centroid of the benzene molecule, respectively. A cone angle of 159° was calculated for the steric pocket of the phosphane ligand. Positional disorder over two sets of sites in the methine and one of the methyl groups of the isopropyl substitutent resulted in a refined 0.528 (5):0.472 (5) ratio. The crystal packing is consolidated by non-classical C—H...Cl interactions.
The title compound, C6H14O6, the sugar alcohol corresponding to L-talose, was crystallized from aqueous solution. Colourless block-shaped single crystals suitable for single-crystal X-ray diffraction analysis were obtained. The title compound crystallizes in the monoclinic space group P21, with one molecule in the asymmetric unit. In the crystal, all six hydroxy groups act as donors in O—H...O hydrogen bonds, forming a three-dimensional hydrogen-bonded network. The crystal structure of its enantiomer, D-altritol (D-talitol), has been reported previously [Kopf et al. (1991). Carbohydr. Res. 217, 1–6].
A new imidazole-based N-heterocyclic carbene iridium(I) cationic complex with a tetrafluoridoborate counter-anion, [Ir(C8H12)(C7H12N2)(C18H15P)]BF4, has been synthesized and structurally characterized. The complex cation has a distorted square-planar conformation around the IrI atom, formed by a bidentate cycloocta-1,5-diene (COD) ligand, a phosphane ligand, and an N-heterocyclic carbene (NHC) ligand. The complex crystallizes in the triclinic space group P1 with one cationic Ir-NHC complex and one disordered [BF4]− anion in the asymmetric unit. Bond lengths and bond angles are as expected for an Ir-NHC complex. Several non-classical C—H...F hydrogen-bonding interactions between the various ligands (triphenylphosphane, NHC, and COD) and the tetrafluoridoborate anion orient the metal cationic complex and the counter-anion in the crystal structure.
The title compound, C16H13NS, crystallizes in the monoclinic space group P21/c with two independent molecules in the asymmetric unit. Both molecules adopt a non-planar structure. No classical hydrogen bonds are found in the crystal structure.
The title compound, C7H14O6, was prepared from an equimolar mixture of D- and L-sorbose (D:L = 1:1) by Fischer glycosidation in methanol and crystallized from water. The title compound crystallizes in the orthorhombic space group Pna21. The asymmetric unit contains one molecule each of methyl α-D-sorboside and methyl α-L-sorboside. In the crystal, the molecules are linked by O—H...O hydrogen bonds, forming a two-dimensional network parallel to (001).
The structure of the title compound, C7H8N2O2, is reported and completes structural characterization for the family of methyl-2-nitroaniline isomers. Bond lengths and angles conform to reported values in other methyl-2-nitroaniline structures, except for the large angle [36.82 (4)°] formed between the phenyl ring and nitro group mean planes. This large angle is due to steric crowding by the neighboring methyl group, a result that is confirmed by an ab initio geometry optimization in vacuo that yields a similar interplanar angle (38.28°). In the extended structure, the molecules form inversion-related pairs that belong to neighboring supramolecular spiral stacks parallel to c. The stacks form around a 41 axis with N—H...N hydrogen bonding between molecules related by −1/4 of a turn at the core and peripheral N—H...O hydrogen bonds to molecules related by +3/4 of a turn.
The title compound, C20H19F3O4, crystallizes with two independent molecules with similar geometry. In both molecules the tetrahydropyran, cyclohexene and cyclohexane rings of the xanthene moiety adopt half-chair, half-boat and chair conformations, respectively. In the extended structure, O—H...O hydrogen bonds between hydroxy and carbonyl groups link molecules into chains propagating along [100].
The title compound, C22H19NO2, is an imino-ketone Schiff base. The configuration about the azomethine bond is E. The aromatic rings of the 1,2-diphenylethanone moiety are inclined to each other by 80.43 (7)°. The 4-ethoxyphenyl ring is inclined to the phenylethanone ring by 81.91 (7)° and to the phenyl ring to which it is trans by 68.56 (7)°. In the crystal, four symmetry-related molecules are linked by C—H⋯O hydrogen bonds to form square-like units with an R34(36) ring motif, which are linked through bifurcated C—H⋯O hydrogen bonds to form sheets parallel to the (101) plane.
The title complex, [Cu(C26H23N4O2)Cl], has resulted from C—C bond formation during synthesis. The crystal structure comprises a tetradentate ligand, (E)-2-{2-[(2-hydroxybenzylidene)amino]-2-(pyridin-2-yl)-1-[(pyridin-2-ylmethyl)amino]ethyl}phenolato, binding through three N and one O atom, and an additional chlorido ligand. The coordination environment of the central copper(II) atom is slightly distorted square-pyramidal with a geometry index τ5 of 0.034.
The title compound, C9H9Cl2NO2, crystallizes in the triclinic space group P1 with six molecules in the asymmetric unit. Structure determination at 100 K from a two-component twin crystal shows that the six crystallographically independent molecules adopt closely similar conformations. The dichlorophenyl and acetamide planes form a dihedral angle of ca. 10.0° (mean of six molecules), while the methoxy substituent is oriented nearly orthogonal to the aromatic ring (mean dihedral angle = 88.5°). In the extended structure, the molecules are linked by N—H⋯O hydrogen bonds into infinite chains extending along [110], giving rise to three independent motifs of alternating molecules (ABABAB⋯, CDCDCD⋯, and EFEFEF⋯). Numerous weak C—H⋯O and C—H⋯Cl hydrogen bonds consolidate the packing.
The title compound, C20H14S2, was synthesized from a dimethyl-substituted thiophene precursor using an oxidative photocyclization reaction. The molecule has a puckered structure due to steric crowding and the extended structure is consolidated by C—H⋯π interactions between columns of stacked molecules.
