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1.
Melvyn Rowen Churchill David George Churchill My Hang Vo Huynh Kenneth J. Takeuchi Ronald K. Castellano Donald L. Jameson 《Journal of chemical crystallography》1996,26(3):179-183
The title compound lies on a site of C2 symmetry, with the two planar pyrazolyl moieties oriented at 86.1° to one another. The hydrogen atoms were located and refined. 相似文献
2.
A novel oxovanadium(IV) complex with tridentate schiff base and bidentate phenanthroline ligands, VO(o-van)(phen) 2H2O[o-van-gly: o-vanillin-glycine; phen: phenanthroline], was synthesized and characterized by elemental analysis, IR and UV-vis spectra. The crystal structure was determined by X-ray single crystal diffraction analysis. The crystal of title complex (C22H21N3O7V, Mw = 490.36) belongs to triclinic, space group P-1 with the following crystallographic parameters: a = 9.247(3) Å, b = 10.125(4) Å, c = 13.100(5) Å, = 106.343(6), = 96.042(7), = 101.726(7), V = 1135.0(7) Å3, Z = 2, Dc = 1.435 Mg m–3, (MoK = 0.485 mm–1, F(000) = 506, and final R1 = 0.0779, wR2 = 0.1598 for observed reflections 1606 (I > 2(I)). V(IV) is six-coordinate with three oxygen atoms and three nitrogen atoms in a distorted octahedral geometry. The complex forms a 3-D network via – stacking and hydrogen bonds. 相似文献
3.
Leonard R. MacGillivray Michelle M. Siebke 《Journal of chemical crystallography》2001,31(7-8):373-376
The crystal and molecular structure of molecular cleft 2,7-di-tert-butyl-9,9-dimethyl-4,5-xanthenedicarboxylic acid (1) is reported. Crystal data for 1: triclinic, space group P, a = 7.934(2), b = 10.387(2), c = 14.084(3) Å, = 96.049(3), = 101.231(4), = 95.635(4)°, V = 1123.7(4) Å3, and D
c = 1.21 g/cm3, for Z = 2. The molecule crystallizes as a cyclic, hydrogen-bonded dimer held together by four O–H······O hydrogen bonds involving four carboxyl groups each of which interact by way of a cyclic hydrogen-bonded motif. The complex organizes in the solid state to form a 2D layered structure. 相似文献
4.
5.
S.M. Malathy Sony M. Kuppayee M.N. Ponnuswamy J. Manonmani M. Kandaswamy Hoong-Kun Fun 《Journal of chemical crystallography》2003,33(12):925-932
Structure and conformation of three tridentate ligands are determined. All these three compounds crystallize in different space groups, the details are as follows: Bis[(3,5-dimethyl,2-hydroxy)-2-hydroxy-5-methoxy]benzylcyclohexylamine (DHBC): monoclinic I2/a (a = 17.691(1) Å, b = 9.707(1) Å, c = 24.235(2) Å, = 91.028(1)°); bis[(3,5-dimethyl,2-hydroxy)-2-hydroxy-5-bromo]benzylcyclohexylamine (DHBrBC): tetragonal P41212 (a = b = 12.1138(1) Å, c = 28.485(1) Å) and bis[(3,5-dimethyl,2-hydroxy)-2-hydroxy-5-bromo]benzylmethylamine (DHBrBM): triclinic
(a = 5.228(1), b = 12.364(1) Å, c = 13.234(1) Å, = 94.04(1)°, = 95.72(1),° = 95.90(1)°). The cyclohexane rings in DHBC and DHBrBC assume chair conformation. Both the phenyl rings are planar in all the molecules and orient at angles of 75.5(1)°, 62.2(1)°, and 53.9(2)°, respectively with each other. The bond angles around N atom show the sp3 character. Inter- and intramolecular O–HN and O–HO types of hydrogen bondings stabilize the molecules in the unit cell in addition to van der Waals forces. 相似文献
6.
Dennis A. Edwards Mary F. Mahon Timothy J. Paget 《Journal of chemical crystallography》1996,26(5):361-364
Diphenylphosphinylacetic acid crystallizes in the monoclinic space groupP2l/n with unit cell dimensionsa=5.6875(7),b=17.049(4),c=13.471(2) Å, =93.36(1)° and Z=4. The molecular packing consists of hydrogen bonded chains arising from intermolecular interactions between a carboxylic acid hydroxyl group and an oxygen of an adjacent phosphine oxide moiety. 相似文献
7.
William H. Watson Guanmin Wu Michael G. Richmond 《Journal of chemical crystallography》2004,34(10):709-716
The reaction of p-toluenethiol with 4,5-dichloro-4-cyclopenten-1,3-dione in 1,2-dichloroethane with added DBU affords good yields of the new bidentate sulfide ligand 4,5-bis(p-tolylthio)-4-cyclopenten-1,3-dione. The title compound was isolated by column chromatography and characterized in solution by IR and NMR spectroscopies. The solid-state structure of RC=CRC(O)CH2C(O) (where R = p-tolylthio) was solved by X-ray crystallography. 4,5-Bis(p-tolylthio)-4-cyclopenten-1,3-dione crystallizes in the monoclinic space group P2
1/c, a = 14.203(3) Å, b = 6.181(1) Å, c = 20.372(4) Å, = 106.111(3)°, V = 1718.1(6) Å3, Z = 4, and d
calc = 1.316 mg/m3; R = 0.0743, R
w = 0.1693 for 3958 reflections with I > 2(I). The redox properties of 4,5-bis(p-tolylthio)-4-cyclopenten-1,3-dione have been examined by cyclic voltammetry in CH2Cl2 solution, where a quasireversible reduction wave at –1.10 V was found. The reduction behavior is discussed relative to the nature of the LUMO level, which has been determined by extended Hückel MO calculations. The redox chemistry and the LUMO of our bidentate sulfide ligand are contrasted with the known redox chemistry and the LUMO composition of the corresponding bidentate phosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd). 相似文献
8.
J. Wouters F. Moureau Ph. Perpète B. Norberg G. Evrard F. Durant 《Journal of chemical crystallography》1994,24(9):607-614
In order to examine the possibility of hydrogen bonding around the flavin ring, an X-ray diffraction study of the title compound was undertaken. Crystals of lumiflavin hydrochloride hydrate [2(C13H12N4O2) 4 HCl 7 H2O] are triclinic, space group
,Z=2,a=11.064(1),b=17.903(1),c=9.891(1)Å, =111.9(6), -96.4(8), =91.6(7)°. We present the crystal structure of this compound and compare it with other flavin derivatives and with the structure of the active site of some flavoproteins. 相似文献
9.
Zedong Dong Victor G. Young Jr. Eric J. Munson Steve A. Schroeder Indra Prakash David J.W. Grant 《Journal of chemical crystallography》2003,33(10):787-793
The benzene and ethanol solvates of neotame crystallized from solutions of neotame anhydrate in benzene and ethanol, respectively. The crystal structures of the two solvates were determined by single-crystal X-ray diffraction using synchrotron radiation. The benzene solvate crystallizes in the monoclinic space group, P21, Z = 2, with one neotame molecule and one benzene molecule per asymmetric unit. The cell constants are a = 13.060 (6) Å, b = 5.582 (2) Å, c = 17.954 (9) Å, and = 102.079 (15)°. The ethanol solvate crystallizes in the orthorhombic space group, P212121 with Z = 8 (Z = 2). The cell constants are a = 10.047 (4) Å, b = 17.001 (4) Å, and c = 28.948 (7) Å. Intermolecular hydrogen bonding among neotame molecules is evident in the two crystals. The benzene solvate has a nonpolar region containing the benzene molecules, with the benzene rings and alkyl chains of the neotame molecules. 相似文献
10.
Yong-Hong Zhou Rong-Chao Zhang Qian Zhang Qiao-Ya Tang 《Molecular Crystals and Liquid Crystals》2018,669(1):134-144
Four novel coordination compounds, namely, [Cd2(pydc)2(bpp)2(H2O)2]? bpp?2H2O (1), [Zn(Hpydc)2]?3H2O (2), [Cd(dhb)2(phen)2] (3), and [Zn(L)(phen) (H2O)] (4) (H2pydc?=?2,6-pyridinedicarboxylic acid, Hdhb?=?2,6-dihydroxybenzoic acid, H2L?=?5-((2'-cyano-1,1'-biphenyl-4-yl) methoxy)isophthalic acid, bpp?=?1,3-bis(4-pyridyl)propane, and phen?=?1,10-phenanthroline) have been hydrothermally synthesized and characterized by IR spectroscopy, thermogravimetric analysis and X-ray single crystal diffraction analyses. Compounds 1, 2 and 3 feature zero-dimensional (0D) structures and 1 is further extended to one-dimensional (1D) chain structure through C-H???O hydrogen bonding interactions. Compound 4 exhibits 1D chain structure. The luminescent properties of compounds 3 and 4 have also been studied. 相似文献
11.
Abstract Proton transfer occurred during co-crystallization of 1,2-(4-pyridyl)ethane with 2-(4-hydroxyphenylazo)benzoic acid to yield
a salt comprising a 1:2 ratio of 1,2-bis(4-pyridinium)ethane dications and 2-(4-hydroxyphenylazo)benzoate anions. Centrosymmetrically
related anions associate by charge-assisted O–H···O hydrogen bonds to form 24-membered {···OC3N2C4OH}2 synthons. These are connected into a supramolecular polymer via charge-assisted N–H···O hydrogen bonds involving the 1,2-bis(4-pyridinium)ethane
dications. The compound crystallizes in the triclinic space group P−1 with a = 8.517(4) ?, b = 9.110(5) ?, c = 10.477(5) ?, α = 96.850(13)°, β = 94.446(12)°, γ = 104.946(10)° and Z = 1 {two anions and a dication}.
Index Abstract Supramolecular chains mediated by charge-assisted O–H···O and N–H···O hydrogen bonding are found in the salt containing a
1:2 ratio of 1,2-bis(4-pyridinium)ethane dications and 2-(4-hydroxyphenylazo)benzoate anions.
相似文献
12.
J.S. Casas E.E. Castellano M.S. García-Tasende A. Sánchez J. Sordo J. Zukerman-Schpector 《Journal of chemical crystallography》1999,29(6):725-727
2-S-Methylthiouracil crystallizes in the triclinic space group P
with unit cell dimensions a = 5.508(4), b = 7.175(3), c = 8.522(2) Å, = 80.83(2), = 80.43(3), = 76.86(3)°, and Z = 2. The molecule exists in the crystal in the lactam form and is essentially planar. The molecular packing consists of molecules linked in centrosymmetric hydrogen-bonded pairs. The effects of methylation and subsequent metallation on the 2-thiouracil structure are discussed. 相似文献
13.
The crystal structures of threo-ifenprodil [threo-2-(4-benzyl-piperidin-1-yl)-1-(4-hydroxyphenyl)-propan-1-ol] (1), potent NMDA receptor antagonist, and two related, biologically active compounds: threo-2-(4-benzyl-piperidin-1-yl)-1-(4-fluorophenyl)-propan-1-ol (2) and 4-benzyl-1-phenethyl-piperidinium chloride (3) have been determined by X-ray structure analysis of single crystals. Compound 1 crystallizes in an orthorhombic system, with a space group Pna21 (a = 34.843(3) Å, b = 6.0261(13) Å, c = 8.9343(9) Å), compound 2 – in a monoclinic space group P21/c (a = 14.194(1) Å, b = 6.2831(6) Å, c = 20.948(1) Å, = 101.762(6)), and compound 3 – in an orthorhombic space group Pbca (a = 10.4627(8) Å, b = 11.2166(6) Å, c = 31.669(2) Å). The piperidine rings are close to ideal chair conformations, the substituents are in equatorial positions. Overall shapes of the molecules, defined by the dihedral angles between the terminal aromatic rings, are very similar in all three cases. In 1 and 3 the crystal packing is mainly determined by the hydrogen bonds, while in case of 2 – by weak van der Waals interactions. The molecules of 1 and 3 are disordered, and the disorder is caused by a rotation around the N–C bond. 相似文献
14.
Rasim Tanbug Kristin Kirschbaum A. Alan Pinkerton 《Journal of chemical crystallography》1999,29(1):45-55
Two energetic salts of the melaminium cation have been prepared and structurally characterized from room temperature X-ray single crystal diffraction data. Melaminium dinitramide (I), triclinic, P1¯, a = 6.6861(11), b = 6.9638(16), c = 10.447(2) Å , = 99.07(3), = 98.30(3), = 108.50(3)°, V = 445.6(2) Å3, and Z = 2. Melaminium nitrate (II), monoclinic, P21/c, a = 3.5789(7), b = 20.466(4), c = 10.060(2) Å, = 94.01(2)°, V = 735.0(3) Å3, and Z = 4. The crystal structures of both salts show distinct monoprotonated melaminium cations and dinitramide- or nitrate anions, respectively. Efficient packing in the solid state is achieved by extensive hydrogen bonding between two-dimensional zigzag ribbons of the melaminium cations and the respective anions resulting in high densities of the solid state structures of 1.74 (I) and 1.71 g/cm3 (II). 相似文献
15.
Zhiyong Hu Michaele J. Hardie Pannee Burckel A. Alan Pinkerton Paul W. Erhardt 《Journal of chemical crystallography》1999,29(2):185-191
2,4-Dihydroxybenzaldehyde can be acylated at the 2 position if the more reactive 4 position is first protected as the methylmethoxy ether. Deprotection permits isolation of 2-benzoyloxy-4-hydroxybenzaldehyde. 2,4-Dihydroxybenzaldehyde, C7H6O3, crystallizes in P21/c, with a = 7.3762(6), b = 11.7455(9), c = 7.3149(6) Å, = 90.533(2)°, Z = 4, and D
X
= 1.448 g cm–3. The individual molecules are characterized by an intramolecular hydrogen bond. The molecules form sheets with additional intermolecular hydrogen bonds. 2-Benzoyloxy-4-hydroxybenzaldehyde, C14H10O2, crystallizes in Pca21, with a = 24.2629(14), b = 3.8445(2), c = 12.3727(8) Å, Z = 4, and D
X
= 1.394 g cm–3. The molecules consist of two planar halves twisted by 51.63(5)° about the ester linkage. Intermolecular hydrogen bonding joins the molecules into ribbons approximately parallel to c. 相似文献
16.
J. L. Edwards G. N. Maracas K. T. Shiralagi K. Y. Choi R. Droopad 《Journal of Crystal Growth》1992,120(1-4):78-83
Spectroscopic ellipsometer is used to monitor the MBE growth of quantum well structures. Real time monitoring of the growth enabled the measurement of growth rate and correlation with RHEED oscillations. The growth of a single GaAs/AlAs quantum well is also monitored in real time using multiple wavelengths. Interface roughness of the interrupted “inverted” AlAs/GaAs interface was also monitored with SE. Under our growth conditions, we measure approximately a 2 ML interfacial region at the inverted interface. A correlation with photoluminescence is also discussed. 相似文献
17.
Melvyn Rowen Churchill David George Churchill My Hang Vo Huynh Kenneth J. Takeuchi Ronald K. Castellano Donald L. Jameson 《Journal of chemical crystallography》1996,26(2):93-97
The title compound consists of two planar pyrazolyl fragments oriented at 73.0° to each other and linked to a common carbon atom. All hydrogen atoms were located unambiguously and their positions were refined. 相似文献
18.
Àngels Leiva William Clegg Lourdes Cucurull-Sánchez Pilar González-Duarte Josefina Pons 《Journal of chemical crystallography》1999,29(10):1097-1101
Silver(I) complexes of 6-methyl-2-pyridinecarboxylic acid (HL) have been prepared, and the crystal structure of [Ag(L)(LH)] has been determined from X-ray diffraction data. This complex crystallizes in the monoclinic space group P21/n, with a = 13.4055(13), b = 7.1012(7), c = 15.588(2) Å, = 112.779(2)°, and Z = 4. Anionic [AgL2]– units are linked together by protons in approximately symmetrical linear O—H—O hydrogen bonds involving uncoordinated carboxylate oxygen atoms, to give polymeric chains. The most significant intermolecular interaction between adjacent parallel chains is offset ring stacking of pairs of aromatic rings with a perpendicular distance of 3.27 Å. The Ag coordination geometry is highly distorted tetrahedral, from two pyridine N atoms and two carboxylate O atoms, each ligand forming a five-membered chelate ring. 相似文献
19.
The title compound is a structurally related isomer of diltiazem, a well known drug. This compound (C18H17NO5S) crystallizes in the space group P21/n with a = 13.803(4), b = 7.704(3), c = 16.093(3) Å, β = 105.37(2)º, Z = 4, V = 1650.1(9) Å3. The least‐squares refinement gave residual index R = 0.067 for 2831 observed reflections. The distorted seven‐membered ring in the molecule shows twist‐boat conformation. Hydrogen bonds in which the amide group at one molecule and a carbonyl group in the adjacent molecule are involved to form centrosymmetric dimers in the crystal. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
20.
D. Michelle Motley Judith A. Walmsley Julio Zukerman-Schpector Edward R. T. Tiekink 《Journal of chemical crystallography》2009,39(5):364-367
Abstract The gold(III) atom in [Au(NH2CH2CH2NH2)Cl2]NO3 is chelated by the ethylenediamine (en) ligand and the approximately square planar geometry is completed by two chloride
atoms. Weak Au···O and Au···Cl contacts are noted above and below the square plane leading to a tetragonally distorted octahedron
for the gold(III) center. Extensive charge-assisted hydrogen bonding of the type N–H···O leads to the formation of a 2-D array
and layers are consolidated into a 3-D network via C–H···O and C–H···Cl contacts. The compound crystallizes in the orthorhombic
space group Pbca with a = 10.3380(11) ?, b = 8.2105(7) ?, c = 19.625(2) ?, and Z = 8.
Index Abstract Square planar complex cations form additional Au···O and Au···Cl interactions to form a tetragonally distorted octahedron
for gold. The ionic components are connected into a 2-D array via charge-assisted N–H···O hydrogen bonding interactions.
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