Showing papers in "Acta Crystallographica Section E-structure Reports Online in 2007"

Abstract: The uncertainty associated with the position of one H atom in curcumin, C21H20O6, has been resolved by establishing the enol tautomeric form supported by an intra­molecular O—H⋯O hydrogen bond.

Abstract: # 2007 International Union of Crystallography All rights reserved The title Mn complex, [Mn(C9H10NO2)2(H2O)4] 2H2O, is monomeric and centrosymmetric. It contains two 4-dimethylaminobenzoate ligands, four coordinated and two uncoordinated water molecules, all ligands being monodentate. The four O atoms in the equatorial plane around the Mn atom form a slightly distorted square-planar arrangement, while the distorted octahedral coordination is completed by the two water O atoms in the axial positions. In the crystal structure, intraand intermolecular O—H O hydrogen bonds link the molecules into chains.

Abstract: The structure of the title compound, C7H8BrNO2S, closely resembles those of other alkyl sulfonanilides. The mol­ecules in the crystal structure are linked into zigzag chains in the b-axis direction via N—H⋯O hydrogen bonds.

Abstract: Fe(AsO4)·2H2O was obtained hydro­thermally from an aqueous solution of iron(III) chloride, ethyl­enediamine and arsenic acid. The structure features six-coordinate iron with sulfate anions acting as bridging ligands.

Abstract: The structure of the title compound (4FPMSA), C7H8FNO2S, closely resembles those of N-phenyl­methane­sulfonamde (PMSA) and other alkyl sulfonanilides. The substitution of either the fluoro, bromo or nitro group at the para position of PMSA does not change the space group, unlike in the case of meta substitutions in PMSA. The geometric parameters in PMSA, 4FPMSA, 4BPMSA and 4NPMSA are similar except for some difference in the angle S2—N5—C6 and some torsional angles. As in other alkyl sulfonanilides, the amide hydrogen sits alone on one side of the plane of the benzene ring, while the whole methane­sulfonyl group is on the opposite side of the plane. It is thus available to a receptor mol­ecule during biological activity. The mol­ecules in the title compound are packed into a layer structure in the a-axis direction via N—H⋯O hydrogen bonds [H⋯O = 2.08 (2), N⋯O = 2.911 (6) A and N—H⋯O = 164 (6)°].

Abstract: In the title compound, C14H12N2O3, the dihedral angle between the two benzene rings is 21.70 (4)°. An intra­molecular O—H⋯N hydrogen bond generates an S(6) ring motif. In the crystal structure, the mol­ecules are linked by inter­molecular O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds into a three-dimensional framework.

Abstract: The title ZnII complex, [Zn(C7H4FO2)2(C10H14N2O)2(H2O)2], is centrosymmetric. It contains two 4-fluoro­benzoate and two diethyl­nicotinamide ligands and two water mol­ecules, all ligands being monodentate. The four O atoms in the equatorial plane around the Zn atom form a slightly distorted square-planar arrangement, while the distorted octa­hedral coordination is completed by the two N atoms in the axial positions. In the crystal structure, O—H⋯O hydrogen bonds link the mol­ecules into infinite chains.

Abstract: In the title compound, [Cd(C6H7N2O5)2], the Cd atom lies on an inversion center and has a slightly distorted octa­hedral geometry. The equatorial plane contains two bidentate 5-carb­oxy-2-methyl-1H-imidazole-4-carboxyl­ate monoanionic ligands. Two coordinated water mol­ecules occupy the axial sites. Inter­molecular N—H⋯O hydrogen bonds link the mol­ecules into chains, which are further connected by inter­molecular O—H⋯O hydrogen bonds, resulting in a three-dimensional supra­molecular framework.

Abstract: The title compound, C21H16FNO3·CH3OH, was synthesized by the reaction of 1-naphthol with methyl cyano­acetate and 3-fluoro­benzaldehyde in methanol under microwave irradiation. The pyran rings of the two independent mol­ecules in the asymmetric unit adopt boat conformations. The crystal packing is stabilized by inter­molecular N—H⋯O, O—H⋯O and C—H⋯π inter­actions.

Abstract: The crystal structure of Li3P has been reinvestigated and confirmed by single-crystal data. The structure is built of Li+ and P3− ions stacked in two kinds of layers perpendicular to the c axis. Atoms Li1, Li2 and P reside at positions of \overline{6}m2, 3m and \overline{6}m2 site symmetry, respectively. The only free parameter, z, for Li2 is found to be 0.5839 (4).

Abstract: The centrosymmetric title compound, [(NpO2)2(C7H4FO2)2(C10H8N2)2], contains the dimeric dioxocation (NpO2+)2 in which two of the four O atoms bridge the Np atoms Two bidentate chelating-bridging fluoro­benzoate anions link the Np atoms of the dimeric cation The N atoms of the 2,2′-bipyridine ligand occupy two positions in the equatorial plane of the distorted penta­gonal bipyramid, forming a five-membered metallacycle

Abstract: The structure of the title compound (4NPMSA), C7H8N2O4S, closely resembles those of N-phenyl­methane­sulfonamide (PMSA) and N-(3-nitro­phen­yl)methane­sulfonamide (4NPMSA), with slightly different geometric parameters. The substitution of a nitro group at the para position of PMSA does not change the space group, unlike the case of meta substitution (3NPMSA), where it changes from monoclinic P21/c to triclinic P\overline{1} [Gowda, Foro & Fuess (2007c). Acta Cryst. E63, o2337]. The N—H H atom and the methyl­sulfonyl group are trans to one another across the plane of the benzene ring. Thus, the amide H atom is available to a receptor mol­ecule during biological activity. An N—H⋯O hydrogen bond links the mol­ecules into centrosymmetric dimers.

Abstract: A new high-pressure phase of the title amino acid (systematic name: 2-ammonio-4-methyl­penta­noate), C6H13NO2, is reported, with one molecule per asymmetric unit, in contrast to the atmospheric pressure phase, (I), reported by Harding & Howieson [Acta Cryst. (1976). B32, 633–634], which has two mol­ecules in the asymmetric unit. The packing consists of a double layer structure, similar to those of (I) and other amino acids with non-polar side chains.

Abstract: The conformation of the N—H bond is anti to the m-nitro substituent in the structure of the title compound, C7H8N2O4S. The mol­ecules are linked into centrosymmetric dimers through an N—H⋯O hydrogen bond.

Abstract: The amino group in the 3 position of the title compound, C5H7N3, is significantly displaced out of the plane of the heteroaromatic ring. Hydrogen bonds between the amino groups and the pyridine N atom link neighbouring mol­ecules into chains along the crystallographic c axis in a similar manner to that in 4-amino­pyridine. Additional hydrogen bonds lead to the formation of a three-dimensional network.

Abstract: The title compound, [Co2(C9H4N2O4)2(H2O)8]·5H2O, contains two CoII ions that are bridged by two 1H-benzimidazole-5,6-dicarboxyl­ate ligands to form an M2L2 type complex (M = metal and L = ligand) There are two crystallographically distinct M2L2 units, each on an inversion centre, along with coordinated and uncoordinated water mol­ecules, in the asymmetric unit The CoII ions are octa­hedral Extensive hydrogen bonding exists between the complex and water mol­ecules, and this helps to stabilize the crystal structure One water molecule is disordered over two sites with occupancies 084:016

Abstract: In the title compound, C13H14O2, a derivative of isocoumarin, the packing is stabilized by intermolecular C-H center dot center dot center dot O interactions.

Abstract: There are two mol­ecules in the asymmetric unit of the title compound, C10H12N2O3, with almost identical conformations. The crystal structure is stabilized by inter­molecular N—H⋯O hydrogen bonds.

Abstract: In the title compound, C19H18NO2+. C7H7SO3−, the cation is almost planar and the benzene ring of the anion makes dihedral angles of 59.17 (9) and 60.59 (10)° with the mean planes through the quinolinium and benzene ring of the cation, respectively. The cations and anions are packed as alternate layers along the b axis. These layers are inter­connected through O—H⋯O and C—H⋯O inter­actions to form a three-dimensional network. The structure is stabilized by these inter­actions and C—H⋯π inter­actions.

Abstract: In the title compound, C8H6N2OS, the planar oxadiazole ring is effectively coplanar with the phenyl ring. This facilitates the formation of N—H⋯S inter­actions, leading to a thione tautomer in the solid state, and the formation of centrosymmetric dimers.

Abstract: The X-ray crystal structure of hexa­iodo­benzene, C6I6, is reported with greatly improved precision after redetermination at 100 K. The compound is isostructural with hexa­chloro­benzene and hexa­bromo­benzene. The mol­ecule lies on an inversion centre.

Abstract: The title compound, K3.5[H4.5α-PtMo6O24]·5.5H2O, containing the hexa­molybdoplatinate(IV) polyanion, was isolated at pH 2.85. The complete polyanion has no crystallographic symmetry. The [H4.5α-PtMo6O24]3.5− polyanions form an inversion-generated dimer, viz. [H9(PtMo6O24)2]7−, via seven strong hydrogen bonds, one of which is disordered. One K+ ion and one water O atom occupy inversion centres.

Abstract: Thymine crystallizes from 50% hydrogen peroxide to give the title hydrogen peroxide water solvate, C5H6N2O2·0.55H2O2·0.45H2O. The disordered peroxide and water mol­ecules occupy the same positions. Thymine mol­ecules are linked together by N—H⋯O hydrogen bonds forming chains parallel to the ac diagonal. Hydrogen peroxide mol­ecules are combined by O—H⋯O hydrogen bonds to give chains parallel to the c axis. Both kinds of chains are organized in a three-dimensional hydrogen-bonded network.

Abstract: In the title compound, C36H24N2O2, the two naphthyl systems are approximately perpendicular to each other and the two 4-cyano­benz­yloxy rings are almost parallel to each other. There are strong π–π inter­actions [3.835 (3) A] between neighbouring mol­ecules. The face-to-face π–π inter­actions between the benzene rings of neighbouring mol­ecules stabilize the crystal structure to form a one-dimensional chain structure along the a axis.

Abstract: In the title compound, C13H14OS, a derivative of thio­isocoumarin, the packing is stabilized by weak C—H⋯S, C—H⋯π and π–π [separation 3.7481 (12) A] inter­actions.

Abstract: The centrosymmetric title compound, {(C4H12N2)[Zn(C14H6N2O8)2]·4H2O}n or {(pipzH2)[Zn(py-2,3-dc)2]·4H2O}n, where py-2,3-dcH2 is pyridine-2,3-dicarboxylic acid and pipz is piperazine, was obtained by the reaction of zinc(II) nitrate tetra­hydrate with (pipzH2)(py-2,3-dc) as a proton-transfer compound in aqueous solution. Each ZnII (site symmetry {\overline 1}) is coordinated in a distorted octa­hedral geometry by four O atoms and two N atoms from two bidentate (py-2,3-dc)2− ligands, which also act as bridging ligands between ZnII atoms. The four donor atoms of the two coplanar (py-2,3-dc)2− anions form a square-planar arrangement around the ZnII centre. In the crystal structure, extensive O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds, as well as ion pairing and π–π stacking [with a distance of 3.8693 (8) A between two aromatic rings] between different fragments, play an important role in the stabilization of the supra­molecular structure.

Abstract: The title compound, C26H18Cl2O4, has two 4-chloro­benzoyl groups that are in an anti orientation and are approximately parallel. The inter­planar angle between the mean planes of the two benzene rings is 7.99 (8)°. These 4-chloro­benzoyl groups are twisted away from the attached naphthalene ring. The two inter­planar angles between the mean planes of the chloro­phenyl groups and the naphthalene ring system are 71.55 (7) and 71.98 (7)°. The torsion angles between the carbonyl groups and the naphthalene ring are 64.9 (2) and 64.4 (2)°, which are far larger than those between the 4-chloro­phenyl groups and the carbonyl groups of 0.0 (2) and −3.8 (3)°. The chloro­phenyl and carbonyl groups are almost coplanar. Inter­molecular hydrogen bonds exist between aromatic H and carbonyl O atoms.

Abstract: The self-assembly of 1,3-diiodo­tetra­fluoro­benzene (13DITFB) and bipyridine (44BPY), C10H8N2·C6F4I2, is driven by halogen bonding. It results in infinite wave-like chains, with the two mol­ecules in a 1:1 mole ratio. Both molecules lie on crystallographic mirror planes, bisecting the central 44BPY C—C bond and passing through two opposite CF groups of 13DITFB. The N⋯I halogen-bonding inter­action is 2.902 (4) A, and the C—I⋯N angle is almost linear [175.6 (2)°]. The chain ⋯13DITFB⋯44BPY⋯ is polar, with all 13DITFB on the wave crest and all 44BPY at the bottom. This is in contrast to similar complexes obtained on self-assembly of 44BPY with 1,3-dibromo­tetra­fluoro­benzene (13DBrTFB), 1,4-diiodo­tetra­fluoro­benzene (14DITFB) or 1,2-diiodo­tetra­fluoro­benzene (12DITFB), where centrosymmetric wave-like chains are observed.

Abstract: The title compound, [Cu(C11H13Cl2N2O)(N3)]n, is an azide-bridged polymeric copper(II) complex. The Cu atom is penta­coordinated by one O and two N atoms of the Schiff base ligand and two bridging N atoms from two azide groups, forming a trigonal–bipyramidal geometry. The structure is further stabilized by an N—H⋯O hydrogen bond.