首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The structure of 5-nitraminotetrazole sodium salt sesquihydrate was determined by X-ray diffraction. The crystals are monoclinic, space group P21/c;a = 3.551(1) Å, b = 21.834(4) Å, c = 9.075(2) Å; = 110.68(3)°; V = 658.3(2) Å3; Z = 4; calc = 1.807 g/cm3. The anion is planar and has an intramolecular hydrogen bond. The negative charge of the anion is localized on one of the oxygens of the nitro group. The sodium cation (c.n.6) is coordinated by three oxygen atoms of different anions and three oxygens of crystallization water. One of the crystallization water molecules is disordered in the unit cell. The anions are hydrogen-bonded with each other and with crystallization water molecules.Original Russian Text Copyright © 2004 by A. M. Astakhov, A. D. Vasiliev, M. S. Molokeev, L. A. Kruglyakova, A. M. Sirotinin, and R. S. StepanovTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 3, pp. 562–565, May–June 2004.  相似文献   

2.
The structure of thep-tert-butylcalix[7]arene 1:3 pyridine complex/clathrate (C77H98O7 · 3 C5H5N) has been determined by X-ray crystallography. The crystal data are as follows: monoclinic, space groupP21/c,a = 37.790(4),b = 9.423(2),c = 29.075(4)Å; = 112.74(2)°;V = 8285(3)Å3;Z = 4;D calc = 1.10 g·cm–3. The hostp-tert-butylcalix[7]arene links one pyridine molecule through a hydrogen bond between one of the seven hydroxy groups and the nitrogen of the pyridine. Two other guest molecules have been found in the crystal lattice, so the title compound may be defined as a complex/clathrate hybrid. The unambiguous conformation of the macrocycle is described by an alternative method, which avoids the use of dihedral angles (and the ambiguities in their values).Part XVII. Ref. [2].  相似文献   

3.
A new method is described for the synthesis of p-(1,1,3,3-tetramethylbutyl)calix[6]arene isolated ina 30 % yield. For the first time the crystal structure isgiven. The crystals are monoclinic, space group C2/c,a = 24.144(5) Å, b = 14.093(3) Å,c = 26.972(5) Å, = 93.36(3)circ, V = 9162(3) Å3, Z = 4. The macrocycle with C2symmetry presents the pinched-cone conformation. It crystallizes with three chloroform molecules, two of them are positioned in the cones shaped by the phenol moieties; the third chloroform is located in the cavity near the hydroxyl groups; this solvent molecule is disordered around the 2 axis. The packing of the complex is described.  相似文献   

4.
The title compound was obtained by reduction of diethyl (ferrocenylmethyl)malonate with lithium aluminium hydride in diethyl ether. The structure of this novel ferrocene derivative was assigned by means of elemental analysis, IR, [1H]NMR, and [13C]NMR spectroscopy. The structure was also confirmed by a single crystal X-ray study. The compound crystallizes in monoclinic P21/a space group with unit cell dimensions: a = 9.7360(6), b = 27.040(5), c = 14.767(3) Å, = 103.835(6)°, V = 3774.8(11) Å3, Z = 12. The asymmetric unit contains three crystallographically independent molecules. In the ferrocenyl moieties, the Fe–C bond distance values are in the range 2.006(5)—2.051(3) Å and C–C distances in the range 1.366(7)–1.425(4) Å. The cyclopentadienyl rings in each of the molecules are mutually twisted by about 13° from the eclipsed conformation. The hydroxyl groups are involved in the intermolecular O–H...O hydrogen bond formation with O-O distances in the range 2.686(3)–2.801(4) Å forming infinite two-dimensional network in a [0 0 1] plane. The crystal structure is additionally stabilized by C–H-O weak intermolecular hydrogen bonds.  相似文献   

5.
The crystal structures of a new solvate of the ditopic receptor 1,3-calix[4]-bis-crown-6, Bis-C6, and of 1,3-calix[4]-bis-(benzo-crown-6), Bis-benzoC6, are reported. Bis-C6.3 CH3CN (1) crystallizes in the monoclinic space group P21/n, a = 14.388(3), b = 26.947(8), c = 14.707(4) Å, = 113.19(3)°, V = 5241(5) Å3, Z = 4. Refinement led to a final conventional R value of 0.092 for 2723 reflections. The structure of (1) differs from the previously reported structure of Bis-C6.4 CH3CN by the conformation of one crown either chain. Two acetonitrile molecules are in the close neighbourhood of the crown ether cavities. Bis-benzoC6.3 CH3CN (2) crystallizes in the monoclinic space group P21/c, a = 10.391(4), b = 17.264(11), c = 30.426(9) Å, = 94.62(3)°, V = 5440(7) Å3, Z = 4. Refinement led to a final conventional R value of 0.106 for 2965 reflections. Two acetonitrile molecules are located near the crown ether cavities, as in (1). One of the crown ether conformations is the same as in the binuclear caesium complex of Bis-benzoC6, supporting the hypothesis of a preorganization of this ligand towards the complexation of this ion; the second crown ether chain is partially disordered.  相似文献   

6.
2,2-Diphenyl-1-picrylhydrazine was crystallized from both tetrahydrofuran and chloroform. The crystal structures of samples from both preparations were determined by X-ray diffraction at low temperatures. Both crystals are clathrates with solvent molecules included as guest species in a host framework formed by the diphenylpicrylhydrazine molecules. The structures are rhombohedral, space groupR3. For the crystal from tetrahydrofuran, at 228 K,a = 25.820(4),c = 15.096(2) Å,Z = 18,R = 0.084 andwR = 0.133. For the crystal from chloroform, at 115 K,a = 25.453(12),c = 15.083(3) Å,Z = 18,R = 0.117 andwR = 0.153. Each unit cell contains three cavities which have approximate cylindrical shape with diameter 7.8 Å and height 6.0 Å, and 3 point symmetry. The integrity of the host framework is maintained only through van der Waals forces rather than through intermolecular hydrogen bonding as is found in many other known organic cathrates. The conformation of the trinitroanilino group of the hydrazine molecule is similar to that in the related trinitroanilinocarbazole molecule. The N-N bond approximates a single bond, and both hydrazine N atoms aresp 2 hybridized.  相似文献   

7.
A new complex of hexa(isothicyanato)chromate(III) hydro-bis(pyridine N-oxide) [(Py)2H]3[Cr(NCS)6] was synthesized and studied by X-ray diffraction analysis. The coordination polyhedra of Cr atoms are the perfect octahedra that form the layered structure. Molecules of pyridine N-oxide form bimolecular cationic associates that compensate the charge on the complex anions. The crystals are triclinic: a = 11.559(2) Å; b = 12.644(3) Å; c = 16,110(4) Å; = 90.02(2)°; = 95.15(2)°; = 98.23(2)°; V = 2320.6(9) Å3; calcd = 1.394 g/cm3. Z = 2, space group P1¯.  相似文献   

8.
Two calix[10]arenes were synthesized: the tert-butylcalix[10]arene (t-Bu-C10) and the detertbutylated analogue (H-C10). Both were crystallized from saturated solutions: t-Bu-C10 from a mixture of toluene and tetrahydrofuran (THF), H-C10 from acetone. In each case, complexes were obtained: H-C10, acetone 1:2 and t-Bu-C10, toluene, THF 1:2.5:0.5. The crystal structures of these twocomplexes and the different conformations of the macrocycles are presented here.For the first, the crystals are triclinic, space group Pmacr{1}, a = 9.037(2)Å, b = 11.447(2)Å, c = 15.197(3)Å, = 80.79(3)Å, = 84.96(3)°, = 88.60(3)°, V = 1545.7(5)Å3, Z = 1; the complex with t-Bu-C10 is orthorhombic, space group Fmm2, a = 32.211(6)Å, b = 32.289(7)Å, c = 12.179(2)Å, V = 12667(4)Å3, Z = 4. The complex from H-C10 shows a pleated loop conformation with H-bonds between acetone and hydroxylgroups. The complex from t-Bu-C10 shows several cavities, in the conesshaped by the phenol moieties and near the hydroxyl groups. The packingsare given for both crystals.  相似文献   

9.
A complex of uranyl perchlorate with imidazolidine-2-one as the molecular ligand, [UO2(Imon)4(H2O)](ClO4)2 (I), was synthesized and structurally characterized by X-ray diffraction analysis. The coordination number of the uranium atom is 7. The nearest environment of the uranyl ion includes four O atoms of the imidazolidine-2-one molecules and one O atom of the water molecule. The perchlorate anions are outer-sphere ligands. The crystals are monoclinic: space group P21/c; a = 16.294(3) Å, b = 16.135(3) Å, c = 9.987(2) Å, = 97.69 (3)°, V = 2603.0 (9) Å3, (calcd) = 2.117 g/cm3, Z = 4. The IR and luminescence spectra of the complex were recorded.Translated from Koordinatsionnaya Khimiya, Vol. 30, No. 12, 2004, pp. 919–924.Original Russian Text Copyright © 2004 by Andreev, Antipin, Budantseva, Tuchina, Serezhkina, Fedoseev, Yusov.  相似文献   

10.
One new polyoxometalate (POM)-based inorganic-organic hybrid [Cd3Ⅱ(HPO4)(Hbpp)(H2O)2]{CdⅡ[P4- Mo6O28H3.5(OH)3]2} (H4tpb)·7H2O (1) (bpp = 1,3-bis-(4-pyridyl)propane, tpb = 1,2,4,5-tetra(4-pyridyl)-benzene) constructed from reduced molybdophosphate [P4Mo6O28H3.5(OH)3]5.5- (P4Mo6), trinuclear CdⅡ-phosphate-Hbpp fragment and protonated tpb has been hydrothermally synthesized and structurally characterized by IR, elemental analyses and single crystal X-ray diffraction. The complex 1 crystallizes in the monoclinic system with the space group P21/c and cell parameters of a = 15.672(12)Å, b = 23.839(19)Å, c = 27.654(2)Å, β = 115.850(10)8, V = 9297.9(12) Å3, Z = 4, R1 = 0.0534 and wR2 = 0.1135. In complex 1, the P4Mo6 units are bridged by CdⅡ ions to form the classic sandwich-type [Cd(P4Mo6)2] dimers, which are further connected into a two dimensional network via the trinuclear CdⅡ subunits. The tpb is synthesized in situ from the bpp ligands and connects the adjacent 2D layers into a 3D supramolecular framework through hydrogen bonding interactions. The electrochemical and fluorescent properties of complex 1 have been investigated.  相似文献   

11.
The molecular and crystal structure of (tricyclohexylphosphine)methylnickel(II) 2,4-pentanedionate has been determined by conventional Patterson and Fourier synthesis and refined anisotropically to a final R value of 0.08, including hydrogen atoms. Coordination about the nickel atom is square-planar with the angles subtended at the nickel being: O(1)NiO(2) = 93°; O(1)NiC(19) = 84°; C(19)NiP = 93°; PNiO(2) = 90°. The NiC(19) σ-bond length is 1.94(1) Å. The cyclohexyl rings are all in the chair conformation having an average CC distance of 1.53 Å and are bonded equatorially to the phosphorus in a tetrahedral arrangement with the average PC distance being 1.861 Å. The pentanedione ligand is planar within experimental error. Molecules of the title compound pack as discrete units in the crystal with no non-hydrogen intermolecular distance being less than 3.6 Å.  相似文献   

12.
p-Benzylcalix[5]arene.3py (py = pyridine) (1) crystallizes in the triclinic space group P1, a = 10.641(3), b = 13.975(3), c = 24.052(12) Å, = 94.60(4), = 91.51(4), = 111.46(2)°, V = 3312(4) Å3, Z = 2. Refinement led to a final conventional R value of 0.065 for 5457 reflections. The calixarene is in a distorted cone conformation. Two pyridine molecules are hydrogen bonded to phenolic oxygen atoms and one of them is included in the hydrophobic cavity of the neighboring calixarene molecule along the a axis.  相似文献   

13.
Crystal Structures of Acid Hydrates and Oxonium Salts. VIII. Dihydrate and Primary Ammonium Salt of Trimetaphosphimic Acid The dihydrate of the crystal structure of trimetaphosphimic acid, H3(PO2NH)3 · 2H2O, crystallizes in the monoclinic space group P21/c with four formula units in the unit cell (a = 7.022(1), b = 14.008(1), c = 9.353(2) Å, β = 93.34(2)°). The primary ammonium salt includes one molecule of methanol in its crystal structure, the orthorhombic space group Pbca contains eight formula units NH4H2(PO2NH)3 · CH3OH in the unit cell (a = 15.025(3), b = 7.264(1), c = 19.252(1) Å). The crystal structures have been determined from three-dimensional X-ray diffraction data collected with an automatic single crystal diffractometer. Both rings of phosphorus and nitrogen atoms show boat conformation with the nitrogen atoms in the imido form. A similar pattern of bond lengths in both molecules and the disorder of one water-oxygen atom in the dihydrate indicate a partial proton transfer from the acid molecule to the water structure. In both structures the anion is linked to other anions by three hydrogen bonds N–H ?O, with an approximate length of 2.9 Å and two very short hydrogen bonds O–H ?O of approximate length 2.5 Å.  相似文献   

14.
Application of high-pressure high-temperature conditions (3.5 GPa at 1673 K for 5 h) to mixtures of the elements (RE:B:S=1:3:6) yielded crystalline samples of the isotypic rare earth-thioborate-sulfides RE9[BS3]2[BS4]3S3, (RE=Dy-Lu), which crystallize in space group P63 (Z=2/3) and adopt the Ce6Al3.33S14 structure type. The crystal structures were refined from X-ray powder diffraction data by applying the Rietveld method. Dy: a=9.4044(2) Å, c=5.8855(3) Å; Ho: a=9.3703(1) Å, c=5.8826(1) Å; Er: a=9.3279(12) Å, c=5.8793(8) Å; Tm: a=9.2869(3) Å, c=5.8781(3) Å; Yb: a=9.2514(5) Å, c=5.8805(6) Å; Lu: a=9.2162(3) Å, c=5.8911(3) Å. The crystal structure is characterized by the presence of two isolated complex ions [BS3]3- and [BS4]5- as well as [□(S2-)3] units.  相似文献   

15.
Summary The crystal structure of the dinuclear complex [Cu2(C26H30-N4O2)(H2O)2](BF4)2 was determined by x-ray crystallography. The crystals are triclinic, P¯1, witha = 10.945(5),b = 8.703(5),c = 8.495(5) Å, = 103.86(3)°, = 105.73(3)°, = 85.77(3)°, V = 756 Å3 Dc = 1.65 g cm–3 for Z = 1. The copper(II) atoms are 5-coordinate and square-pyramidal. Selected bond distances are: Cu-N, 1.91 Å (mean); Cu-O(base) = 1.90(1) and 1.91(1) Å; Cu-O(apical) = 2.47(1) Å; There are O(water)-H ... F interionic hydrogen bonds in the structure. The Cu .. Cu distance is 2.847 Å.  相似文献   

16.
p-Tetrakis(phenylazo)-tetra-hydroxythiacalix[4]arene shows complexing properties with neutral molecules. A complex with pyridine was crystallized and the crystal structure determined. The crystals are monoclinic, space group C2/c, a = 49.953(10), b = 21.566(4), c = 23.448(5) Å, = 105.12(3)°, V = 24386(8) Å 3, Z = 16. Two macrocycles are positioned in such a way that they form a cavity where two pyridine molecules are encapsulated giving a 2:2 endocomplex. 5.5 other pyridine molecules are trapped between the macrocycles, two of them giving H-bonds with the calixarenes.  相似文献   

17.
Bis(2-furoinate)triphenyl- and tri-p-tolylantimony and bis(3-niacinate)triphenylanitmony were synthesized by reacting triarylantimony (Ar3Sb; Ar = Ph, p-Tol) with 2-furancarboxylic and 3-pyridinecarboxylic acids in the presence of hydrogen peroxide. According to X-ray diffraction data, Sb atoms have trigonal bipyramidal coordination polyhedra. The Sb–O distances are 2.117(4), 2.137(4) Å; 2.136(2), 2.158(2) Å, and 2.112(1), 2.101(2) Å, the Sb···O distances are 2.866(4), 2.798(4) Å; 2.816(2), 2.774(2) Å, and 3.054(2), 3.168(2) Å, respectively.  相似文献   

18.
Summary Anhydrous lactitols (A1, α- and β-lactitol), lactitol monohydrate, lactitol dihydrate and lactitol trihydrate were kept for varying times in atmospheres of different relative humidity at 20°C in equivalent size plastic desiccators. The relative humidities (8-95%) were maintained with saturated salt solutions and drying agents (silica gel and phosphorous pentoxide). The composition of the samples was monitored by thermogravimetry, differential scanning calorimetry and X-ray powder diffraction. According to these measurements both lactitol monohydrate and lactitol dihydrate were substantially stable under the conditions used. Lactitol monohydrate converts to lactitol dihydrate at the highest relative humidity used. All phases of anhydrous lactitol convert into a form of lactitol monohydrate but not to lactitol dihydrate, even at the highest relative humidity used. At a high relative humidity lactitol trihydrate easily loses part of its crystal water and converts partly to lactitol dihydrate. At a lower relative humidity, the phase forming from trihydrate is difficult to identify.  相似文献   

19.
The molecular structure and conformation of carvone, a compound with a minty odor, were investigated by means of gas electron diffraction supported by theoretical calculations. Electron diffraction patterns were recorded by heating the nozzle up to 128 °C to obtain enough scattering intensity. The infrared spectrum was also measured by using an absorption cell with a path length of 10 m. The obtained molecular scattering intensities were analyzed with the aid of theoretical calculations and infrared spectroscopy. It was revealed that the experimental data are well reproduced by assuming that carvone consists of a mixture of three conformers that have the isopropenyl group in the equatorial position and mutually differ in the torsional angle around the single bond connecting the ring and the isopropenyl group. It was also found that the puckering amplitude of the ring of carvone is close to those of menthol and isomenthol, a minty compound and its nonminty isomer. The determined structural parameters (rg and ∠α) of the most abundant conformer of carvone are as follows: 〈r(C-C)〉=1.520(3) Å; 〈r(CC)〉=1.360(5) Å; r(CO)=1.225(5) Å; 〈r(C-H)〉=1.104(4)Å; 〈∠CC-C〉=121.1(5)°; 〈∠C-C-C〉=110.4(5)°; ∠C-CO-C=117.1(14)°; 〈∠C-C-H〉=111.1(13)°. Angle brackets denote average values and parenthesized values are the estimated limits of error (3σ) referring to the last significant digit.  相似文献   

20.
Gossindane, the oxidation product of gossypol, demonstrates inclusion properties towards four solvents chosen accidentally. The crystal data of these complexes with ethanol (I), ethylacetate (II), dichloromethane (III) and water (IV) are: (I): C26H30O6· 2C2H5OH, monoclinic, P2/c, a = 8.687(2) Å, b = 10.986(3) Å, c = 14.778(3) Å = 110.94° V = 1317 Å3, Z = 2, R = 0.069, N = 1368; (II): C26H30O6· 0.5C4H8O2, monoclinic, P21/c, a = 8.960(2) Å, b = 21.937(5) Å, c = 14.712(3) Å, = 111.98(2)°, V = 2681 Å3, Z = 4, R = 0.083, N = 2653; (III): C26H30O6· CH2Cl2, monoclinic, P21/c, a = 8.886(2) Å, b = 21.778(6) Å, c = 14.996(4) Å, = 111.31(3)°, V = 2704 Å3, Z = 4, R = 0.131, N = 1580; (IV): C26H30O6·2H2O, monoclinic, C2/c, a = 29.422(9) Å, b = 6.720(2) Å, c = 27.525(9) Å, = 117.43(2)°, V = 4830 Å3, Z = 8. R = 0.096, N = 2240.In the solvates H-bonded host molecules form bilayers with very similar structures and a nearly hydrophobic surface. Guest molecules are placed in channels formed between these bilayers and may be H- bonded to host molecules (ethanol). In the hydrate two water molecules using their H-bonding capacity incorporate gossindane molecules into bilayers.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号