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1.
The crystal structures of two compounds belonging to the isomorphous series of clathrate inclusion complexes of tetraphenylene, 2C24H16·X (with X=benzene (I) and X-cyclohexane (II), were solved. For (I),a=10.0691(1),c=18.431(5) Å, space groupP42/n,Z=2; (II) has a very similar cell.Crystal structure analyses (Nicolet R3m four-circle diffractometer, graphite-monochromated MoK; (I) 926 reflections,R F =12.8%; (II) 1180 reflections,R F =10%) showed that the tetraphenylene molecules use crystallographicC 2 symmetry in the construction of a nearly spherical cavity of point symmetry 4 located about 1/4 1/4 1/4. The geometry of the tetraphenylene molecule agrees well with that reported earlier for the crystals of neat tetraphenylene. The enclosed benzene and cyclohexane guests are necessarily disordered. Thedisorder found for the cyclohexane guest is consistent with its expectedchair conformation. Analysis of the cell dimensions of a number of complexes shows that the tetraphenylene framework adjusts itself according to the steric requirements of the guests. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82003. To obtain copies, see page ii of this issue.Also known as N. Z. Huang.  相似文献   

2.
The X-ray structure of the 1,4-butanediol clathrate ofN,N-[1,3-azulenylenebis(methylene)]bis(trimethyl-ammonium)-diiodide is described, and the differences as well as the similarities to the 1-butanol inclusion of the same host are discussed in detail. The unit cell data of further clathrates of this new type are quoted.Supplementary Data. Details of the crystal structure are available on request from the Fachinformationszentrum Energie-Physik-Mathematik, D-7515 Eggenstein, Leopoldshafen 2, by quoting the depository number CSD50482, the names of the authors, and the journal citation  相似文献   

3.
The title compound C6H4(C7H5N2)2 was prepared by the condensation of o-phenylenediamine with o-phthalic acid and characterized by elemental analysis, IR, UV and ^1H NMR spectra, and its structure was determined by single-crystal X-ray diffraction,showing the compound molecule belongs to (72 point group. A ID chain structure was formed by the intermolecular hydrogen bonds (N(2)H…N(I)).  相似文献   

4.
Using x-ray diffraction analysis, we have determined the molecular structure of the phosphorus-containing podand bis[2-(o-diphenylphosphorylphenoxy) ethyl] ether in the crystal of its benzene solvate. We have established a considerable difference between the conformations of the free podand and its (previously studied) "guest—host" complex with an organic ammonium cation.Institute of Physiologically Active Substances, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 624–629, March, 1992.  相似文献   

5.
The reaction of 2-nitro-(2-pyridylsulfanylmethyl)benzene L with silver nitrate produces a centrosymmetric binuclear complex bis(2-nitro-(2-pyridylsulfanylmethyl)benzene-N,S)-bis(nitrato-O,O)-disilver(Ⅰ), [AgLNO3]2 1. The crystal is of triclinic, space group P1, with a = 7.383(3), b = 8.340(3), c = 12.003(4) A, a = 95.069(6), β = 93.498(5), γ = 102.734(6)°, C24H2oAg2N6-O10S2, Mr= 832.32, V= 715.6(4) A3, Z = 1, Dc = 1.931 g/cm3, F(000) = 412, μ = 1.581 mm-1, R=0.0351 and wR = 0.0749 Each silver atom is tetrahedrally coordinated by two O atoms from bidentate nitrate, one S atom from a ligand and one N atom from another ligand. Furthermore, AgAg interactions have been observed in the complex.  相似文献   

6.
《Mendeleev Communications》2023,33(2):171-173
Crystal structure of widely employed precatalyst [Pd(Ph3P)4] is reported. It crystallizes in P-3 space group [a = 19.0828(8) and c = 26.4423(18) Å] with six molecules per unit cell. It is demonstrated that the phase purity of this important compound can now be routinely controlled via powder X-ray diffraction analysis.  相似文献   

7.
Redetermination of the crystal structure of poly(p-benzamide) was made by using newly collected intensity data. The molecular conformation is TCTC, where the internal rotation angles about the N? C bond of the amide group and about the virtual bond of N-phenyl-C are T (trans) and C (cis) conformations, respectively. Two molecular chains pass through a rectangular unit cell with dimension, a = 7.75 Å, b = 5.30 Å, c (fiber axis) = 12.87 Å, and the space group, P212121-D. The reflection observed at the spacing of 010 may be attributed to the reflection due to another crystal polymorph or the diffuse scattering due to disorder. © 1993 John Wiley & Sons, Inc.  相似文献   

8.
1 INTRODUCTION Metallosupramolecular species with metal-metal interactions have been designed and synthesized due to their potential applications as functional materi- als[1]. For Ag(I) coordination compounds, short Ag(I) –Ag(I) separations have been found in many bi- and polynuclear complexes[2~4], and these short metal- metal distances have been attributed to the ligand ar- chitecture[5, 6]. Thus, the rational design of bi- and polynuclear Ag(I) complexes must recognize the in- here…  相似文献   

9.
1 INTRODUCTION The coordination chemistry of bithioethers with noble metal ions has received considerable attention for a very long time due to their appli- cations in extracting noble metals. A number of Pt(Ⅱ) complexes with such ligands have been reported[1~7], among which some crystal structures have been determined[4~7]. However, most of these structures are Pt(Ⅱ) complexes of a few bithioether ligands with flexible alkyl spacers, RS(CH2)nSR. To our knowledge, the crystal str…  相似文献   

10.
王敏  王志强  王明安  刘军 《有机化学》1996,16(4):357-363
本文合成了主体分子(S, R)-1, 1'-联萘-2, 2'-二羟基磷酰(N-α-苯乙基)胺及8种包合物, 经熔点、结晶形状及元素分析确定了它们的组成; 并经过X-射线衍射分析确定了其乙醇包合物的单晶结构, 晶体属单斜晶系, 空间群P2~1,a=0.9365(1)nm, b=1.2825(7)nm, c=1.1640(3)nm, β=111.71°, Z=2,R=0.0469。其中主体分子形成层状结构, 客体分子处于相邻的层间。  相似文献   

11.
The crystal structure of 1-(2-pyridiniomethyl)-2,4-bis(phenylsulfonyl)benzene bromide, (C24H20NO4S2)+. Br (I) has been investigated by X-ray diffraction (XRD)analysis. The triclinic structure of I (space group P1, a = 7.863 , b = 8.350 , c = 9.043 , = 94.00°, = 97.81°, = 104.62°, Z = 1) was solved by direct methods and refined by full-matrix least-squares analysis in an anisotropic approximation to R = 0.048 for all 4570 reflections collected (CAD-4 automatic diffractometer, CuK ). The geometrical parameters of the organic cation were determined with a sufficient degree of accuracy. The crystal structure of I involves a very strong interionic hydrogen bond N+-HBr.Original Russian Text Copyright © 2004 by A. N. ChekhlovTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 4, pp. 759–763, July–August, 2004.This revised version was published online in April 2005 with a corrected cover date.  相似文献   

12.
A phase diagram of the [Zn(MePy)2(NCS)2]-MePy binary system has been studied by DTA and solubility methods. Two compounds melting incongruently (at 63 and 57°C) have been discovered in the system. They have been obtained as separate phases with crystals of different shape (needles and octahedra). Their composition has been determined by analytical methods and verified by X-ray structural analysis: [Zn(MePy)4(NCS)2]·0.67 MePy·xH2O, wherex depends on the synthesis conditions, and [Zn(MePy)4(NCS)2]·MePy, respectively.The preliminary X-ray study of the first compound (at –100°C) has shown it to be isostructural with the known clathrates of the common formula [M(MePy)4(NCS)2]·0.67MePy·xH2O, where M=Cu, Mn, Mg andx=0–0.33. The unit cell parameters are as follows:a=27.20(1),c=11.202(4) Å, space group ,Z=9.The X-ray study of [Zn(MePy)4(NCS)2]·MePy (at–50°C) has shown it to be analogous to the organic zeolite -phase with the guest MePy molecules located in the channels formed by molecular packing of the [Zn(MePy)4(NCS)2]host. The cell is tetragonal, the space groupI41/a,a=16.845(6),c=23.496(7) Å,V=6667(4) Å3,Z=8,D calc=1.289 g cm–3,R=0.074. The zinc cation is surrounded by a slightly irregular octahedron of six nitrogen atoms of the MePy and NCS ligands. The crystallisation field of the host [Zn(MePy)4(NCS)2] complex in the temperature range concerned is absent in the phase diagram. It suggests contact stabilization of the [Zn(MePy)4(NCS)2] molecule by the guest in the clathrates. Supplementary Data relevant to this paper have been deposited with the British Library at Boston Spa, Wetherby, West Yorkshire, U.K. as Supplementary Publication No. SUP 82166 (15 pages).  相似文献   

13.
This work is devoted to the EXAFS analysis of nanostructured iron(III) oxide synthesized inside the pore system of mesoporous carbon CMK-1. A detailed study of the recording, preparation and evaluation of data recorded in fluorescence mode at the iron K-edge with and without multiple scattering is shown. The results obtained show that the local structure of Fe3+ inside nanostructured iron(III) oxide is different to that of the bulk material. Due to the small particle size, data analysis is much more difficult and data preparation more complex. Incorporating multiple scattering paths in the Fourier transforms and back-transforms during data evaluation gives structural insights that cannot be obtained using other spectroscopic methods, and this technique was used to draw conclusions about the first four coordination spheres of the nanostructured iron(III) oxide.   相似文献   

14.
Cd(CN)2·(CH3O)2CO (1) contains a mineralomimetic framework of Cd(CN)2 analogous to the low temperature form of cristobalite. The host framework is isostructural to those of previously reported Cd(CN)2·G compounds (G = CHCl2CH2Cl2, (CH3)2CHBr3). The dimethyl carbonate molecules in the adamantane-like cage display orientation disorder associated with the location of the carbonyl oxygen atom.Presented at the Sixth International Seminar on Inclusion Compounds, Istanbul, Turkey, 27–31 August, 1995.  相似文献   

15.
The two-dimensional crystal structure of poly(p-phenylene) is investigated by linkedatom Rietveld analysis of the x-ray diffraction powder profile. Two molecular chains are packed in a rectangular pgg unit cell (a = 0.779 nm; b = 0.551 nm) with a paracrystalline shift distortion along the chain axis. The molecular conformation is not rigidly planar; rotations between adjacent phenyl-ring planes in a molecule alternate with an angle of about 20°. The setting angle between the mean molecular plane and the a axis is 55.5°.  相似文献   

16.
Crystal structures are reported for the molecular complexes ofE,E-1-[p-dimethylaminophenyl]-5-[o-hydroxyphenyl]-penta-1,4-dien-3-one (DHDK) with chloroform,m-dinitrobenzene andp-dimethylaminobenzaldehyde. The three complexes (first reported by I. M. Heilbron and J. S. Buck [1] in 1921) have different structures. In DHDK·0.4 CHCl3 (triclinic,a=12.086(6),b=10.323(5),c=8.015(4) Å, =94.58(6), =103.58(6), =110.10(6)o,Z=2,P (assumed)), the host molecules are linked by two hydroxyl carbonyl hydrogen bonds to form centrosymmetric pairs, with the disordered CHCl3 molecules contained in cavities left between the molecule pairs. The complex is a clathrate. In DHDK·m-dinitrobenzene (triclinic,a=21.787(9),b-13.850(5),c=7.759(4) Å, =88.25(5), =84.70(5), =88.86(5)o,P ,Z=4) the DHDK molecules are linked in ribbons through head-to-waist hydroxyl-carbonyl hydrogen bonds. The guest molecules are contained in sinuous channels left between the DHDK ribbons; the host and guest molecules are approximately coplanar. Successive planes are mutually shifted so that the guest molecules are enclosed above and below by host molecules. This is a new structural type, with features resembling those of channel inclusion complexes. In DHDK·p-dimethylaminobenzaldehyde (monoclinic,a=22.331(9),b=12.238(5),c=8.904(4) Å, =92.99(5)o,Z=4,P21/n) the host molecules are arranged so as to leave channels of approximately rectangular cross-sections in which the guest molecules are accommodated. Additional stabilization is achieved by hydrogen bonding between host hydroxyl and guest carbonyl groups. This is a channel-inclusion complex. In the chloroform andp-dimethylaminobenzaldehyde complexes the host molecule has thes-trans, trans conformation but in them-dinitrobenzene complex its conformation iss-cis, trans.Dedicated to Professor Friedrich Cramer on the occasion of his 60th birthday Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication NO. SUP 90076 (13 pages). To obtain copies, see page ii of this issue.Molecular Compounds and Complexes, Part XIV. For Part XIII, see [25].  相似文献   

17.
Fluorinated Dewar benzene (1,2,4-trifluoro-3,5,6-tris(triisopropylsilyl)bicyclo[2,2,0]-hexa-2,5-diene) efficiently prepared from fluoro(triisopropylsilyl)acetylene was thermochemically or photochemically transformed into the corresponding highly crowded fluorinated benzene (1,2,4-trifluoro-3,5,6-tris(triisopropylsilyl)benzene) in excellent yield. The molecular structure of the crowded benzene was determined by X-ray crystallography.  相似文献   

18.
The crystal and molecular structure of 1-(trimethylsilylmethyl)benzotriazole has been established by X-ray diffraction (XRD) analysis. The coordination polyhedron of the silicon atom in this molecule is a tetrahedron. The bond lengths and angles of the 1-(trimethylsilylmethyl)benzotriazole molecule were compared with those of related crystal structures.  相似文献   

19.
The tetramethylammonium hydroxide-water system has been studied by low-temperature differential thermal analysis and X-ray powder diffraction. The melting diagram was constructed for concentrations between 66.7 and 100 mol% H2O. It shows the existence and stability ranges of as many as eight crystalline hydrate phases:- and-Me4NOH·2H2O (phase transition at –85°C, decomposition atca. 105°C), Me4NOH·4 H2O (melting point 44°C, incongruent), and-Me4NOH·5 H2O (phase transition at 42°C, melting point 68°C, congruent),- and-Me4NOH·7.5 H2O (phase transition at 6°C, melting point 16°C, incongruent), and Me4NOH·10 H2O (melting point –20°C, incongruent). The structures of all these phases, except the already known one of-Me4NOH·5 H2O, were determined from single-crystal MoK diffractometer data. The decahydrate and the high-temperature forms of the 7.5-hydrate and the pentahydrate are genuinepolyhedral clathrate hydrates, the first ones reported of a strong base. Their mostly novel three-dimensional anionic host structures, formed by the hydrogen-bonded OH ions and H2O molecules, arefour-connected throughout, in spite of their proton deficiency which is apparently leveled by disorder. Disorder also affects the enclosed cationic Me4N+ guest species. Like the low-temperature form of the pentahydrate, that of the 7.5-hydrate has a clathrate-related, but not fully polyhedral structure, some of the oxygen atoms being three-connected only. The tetrahydrate presents the rare case of both a hydrogen bond of the type OH...OH2 and a (deprotonated) water-channel structure. This is fully ordered and apart from that can be derived from the polyhedral one of the-pentahydrate just by removing the appropriate number of water molecules from certain positions. The structures of- and-Me4NOH·2 H2O contain identical one-dimensionalspiro chains [HO(HOH)/42] with the hydroxide protonnot participating in the hydrogen bonding. The Me4N+ ion is ordered in the and disordered in the phase.Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82076 (66 pages).Dedicated to Dr D. W. Davidson in honor of his great contributions to the sciences of inclusion phenomena.  相似文献   

20.
p-(Methyl,tert-butyl, nitro,tert-butyl) calix[4]arene: toluene, C37H41NO6. C7H8,M r = 687.87, triclinic, ,a = 13.668(2),b = 12.187(2),c = 13.231(1) Å, = 106.78(8), = 77.88(1), = 114.00(1)°,V = 1916.8(8) Å3,Z = 2,D x = 1.19 g cm–3, (CuK ) = 1.54178 Å, = 5.90 cm–1,F(000) = 736,T = 293 K, finalR = 0.068 for 6309 observed reflections. This macrocycle, having different substituents at the positionspara to the hydroxyl groups, is the first one of its type to be studied. The general conformation of this calix[4]arene is compared to similar symmetrical ones. Thetert-butyl groups are not disordered as is usual and toluene is retained between the macrocycles. Two calixarene molecules are positioned to permit atert-butyl group of one to be inside the cavity of the second to establish CH3- interactions.  相似文献   

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