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Chun Yang,Ou-Yang Yan,Qing-Lun Wang,Dai-Zheng Liao
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808000962
Abstract: In the title centrosymmetric zinc(II) complex, [Zn2(C4H13NO2)2(C6H5N)2], each ZnII atom is coordinated by two 2-[(2-oxidobenzylidene)aminomethyl]phenolate (L) ligands and one pyridine (py) molecule in a distorted trigonal-bipyramidal geometry. Each L ligand behaves as a tridentate ligand and provides a phenolate oxygen bridge which links the two ZnII atoms. The ZnL(py) units are linked by π–π interactions between adjacent pyridine molecules, with a centroid–centroid distance of 3.724 , resulting in a two-dimensional structure.
See Mun Lee,Kong Mun Lo,Hapipah Mohd Ali,Seik Weng Ng
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809022259
Abstract: The SnIV atom in the title compound, [Sn(CH3)2(C18H11ClN2O3)], shows a trans-C2NO2Sn trigonal-bipyramidal coordination; the axial O—Sn—O angle is 155.22 (5)°. The tridentate N′-(5-chloro-2-oxidobenzylidene)-3-hydroxy-2-naphthohydrazidate dianion is stabilized by an intramolecular O—H...N hydrogen bond.
Bis[μ-N-(2-oxidobenzylidene)pyridine-2-carbohydrazidato]bis[chlorido(methanol-κO)erbium(III)]  [cached]
Hua Yang
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812013979
Abstract: In the binuclear title complex, [Er2(C13H9N3O2)2Cl2(CH3OH)2], the entire molecule is generated by the application of inversion symmetry. Each ErIII ion is seven-coordinated by two O atoms and one N atom from one N-(2-oxidobenzylidene)pyridine-2-carbohydrazidate (L2 ) ligand, one O atom and one N atom from the symmetry-related L2 ligand, one O atom of a methanol molecule and one chloride anion. The coordination geometry is based on a pseudo-pentagonal bipyramid. Linear supramolecular chains along [010] are formed in the crystal packing through O—H...Cl hydrogen bonds.
2,6-Bis(1H-benzimidazol-2-yl)pyridine methanol trisolvate  [cached]
Ying Chen,Jixi Guo,Xingcai Huang,Ruirui Yun
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809012574
Abstract: In the title compound, C19H13N5·3CH4O, the 2,6-bis(2-benzimidazolyl)pyridine molecule is essentially planar with an r.m.s. deviation for all non-H atoms of 0.185 . The crystal structure is stabilized by intermolecular O—H...O, O—H...N and N—H...O hydrogen bonds and weak π...π stacking interactions with centroid–centroid distances of 3.6675 (16) and 3.6891 (15) . The atoms of one of the methanol solvent molecules are disordered over two sites with refined occupancies of 0.606(8) and 0.394(8).
[1-(5-Bromo-2-oxidobenzylidene)thiosemicarbazidato-κ3O,N1,S](pyridine-κN)nickel(II)  [cached]
Fernanda Rosi Soares Pederzolli,Leandro Bresolin,Johannes Beck,Jörg Daniels
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812028917
Abstract: The reaction of 5-bromosalicylaldehyde thiosemicarbazone with nickel acetate tetrahydrate and pyridine yielded the title compound, [Ni(C8H6BrN3OS)(C5H5N)]. The NiII atom is four-coordinated in a square-planar environment by one deprotonated dianionic thiosemicarbazone ligand, acting in a tridentate chelating mode through N, O and S atoms forming two metalla-rings, and by one pyridine molecule. The complex molecules are linked into dimers by pairs of centrosymmetrical N—H...N interactions. In addition, molecules are connected through intermolecular Br...Br interactions [3.545 (1) ], forming chains along the b-axis direction.
Tris(piperazinediium) bis[tris(pyridine-2,6-dicarboxylato)neodymate(III)] 15.33-hydrate
Zohreh Derikvand,Hossein Aghabozorg,Andya Nemati,Mohammad Ghadermazi
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536807068328
Abstract: The title compound, (C4H12N2)3[Nd(C7H3NO4)3]2·15.33H2O or (pipzH2)3[Nd(pydc)3]2·15.33H2O (in which pipz is piperazine and pydcH2 is pyridine-2,6-dicarboxylic acid), was synthesized by the reaction of NdCl3·6H2O with the proton-transfer compound (pipzH2)(pydc) in aqueous solution. The nine donor atoms of the three pydc2 ligands form a distorted tricapped trigonal–prismatic arrangement around the NdIII center. Considerable C—O...π stacking interactions between CO groups of carboxylate fragments and aromatic rings of pydc2 with distances of 3.135 (5)–3.255 (5) are observed. In the crystal structure, a wide range of hydrogen-bonding [of the types O—H...O, N—H...O and C—H...O, with D...A distances ranging from 2.608 (10) to 3.278 (7) ], ion-pairing and C—O...π stacking interactions connect the various components into a supramolecular structure. There is a high degree of solvent disorder in the structure; the occupancies of five water molecules refined to 0.6, 0.5, 0.4, 0.25 and 0.25.
[(–)-(1S,2S)-N,N′-Bis(2-oxidobenzylidene)-1,2-diphenylethane-1,2-diamine]bis(pyridine)cobalt(III) perchlorate methanol hemisolvate hemihydrate
Yu-Ting Chen
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808031887
Abstract: In the title compound, [Co(C28H22N2O2)(C5H5N)2]ClO4·0.5CH4O·0.5H2O, each CoIII ion is coordinated by the tetradentate N,N′-bis(2-oxidobenzylidene)-1,2-diphenylethane-1,2-diamine ligand [Co—N = 1.900 (3) and 1.903 (3) ; Co—O = 1.885 (3) and 1.891 (3) ] and two pyridine ligands [Co—N = 1.967 (4) and 1.977 (3) ] in a distorted octahedral geometry. The packing of the cations and anions forms voids of 258 3, which are filled by methanol and solvent water molecules with half occupancies. O—H...O hydrogen bonds between solvent molecules, perchlorate anions and water molecules, and between water molecules and O atoms of the ligand, help to consolidate the crystal packing.
Nooraziah Mohd Lair,Hapipah Mohd Ali,Seik Weng Ng
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536808042803
Abstract: The pyridine-coordinated CuII atom in the title Schiff base complex, [Cu(C15H11N3O5)(C5H5N)], is O,N,O′-chelated by the doubly deprotonated Schiff base ligand. The metal centre is in a square-planar coordination geometry.
Cyclolinopeptide B methanol trisolvate
Gabriele Schatte,Shaunivan Labiuk,Bonnie Li,Peta-Gaye Burnett
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536811051488
Abstract: The title compound, C56H83N9O9S·3CH3OH, is a methanol trisolvate of the cyclolinopeptide cyclo(Met1—Leu2—Ile3—Pro4—Pro5—Phe6—Phe7—Val8—Ile9) (henceforth referred to as CLP-B), which was isolated from flaxseed oil. All the amino acid residues are in an l-configuration based on the CORN rule. The cyclic nonapeptide exhibits eight trans peptide bonds and one cis peptide bond observed between the two proline residues. The conformation is stabilized by an α-turn and two consecutive β-turns each containing a N—H...O hydrogen bond between the carbonyl group O atom of the first residue and the amide group H atom of the fourth (α-turn) or the third residue (β-turns), repectively. In the crystal, the components of the structure are linked by N—H...O and O—H...O hydrogen bonds into chains parallel to the a axis.
Crystal structure of tris(pyridine)(salicylaldehyde semicarbazonato(2-))cobalt(III)-trichloropyridinecobaltate(II) at 293 and 120 K
Journal of the Serbian Chemical Society , 2007,
Abstract: The crystal structure of [CoIII(L)(py)3][CoIICl3(py)[ (H2L = salicylaldehyde semicarbazone)was determined by X-ray analysis based on two single crystal X-ray experiments performed at 120 K and 293 K, respectively. It was found that the pyridine ligand of the complex anion is disordered over two positions. The preferential position of this pyridine found at120Kwas explained in terms of the C–H...Cl intermolecular interaction between the tetrahedral [CoII(py)Cl3]- anions. The mer-octahedral geometry of the cation in the presented crystal structure was compared with previously published structures of similar composition, [CoIII(L1)(py)3]+[CoIICl3(py)]-·EtOH and [CoIII(LI)(py)3]+I3- (H2LI = salicylaldehyde S-methylisothiosemicarbazone). Although the tetrahedral [CoIICl3(py)]- anions possess the same charge, they mutually form different intermolecular interactions which can be realized either by C–H...Cl hydrogen bonds or by p-p interactions between the pyridine rings.
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