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1.
利用二苄基二氯化锡和哌嗪单荒酸盐反应,合成了氯代二苄基锡哌嗪单荒酸酯 。通过元素分析、红外光谱和核磁共振氢谱对其结构进行了表征,并用X射线单晶 衍射测定了晶体结构。该化合物属于单斜晶系,空间群为P21,a=0.63635(10nm, b=1.6167(3)nm,c=0.87641(14)nm,β=95.673(2)°,Z=2,V=1.0594(3)nm^3,Dc=1. 560g/cm^3,μ=1.534mm^-1,F(000)=500,R=0.0277,wR=0.0706[I≥2σ(I)]。化合物 中,锡原子五配位畸变三角双锥构型,分子间通过S…S和S…Cl近距作用,形成一 维链状结构。  相似文献   

2.
The review concerns the results of systematic X-ray diffraction studies of the electron density distribution in the crystals of compounds with strong intramolecular hydrogen bonds N-H...O, O-H...O, O-H...N, and N-H...S. The advantages of the topological analysis of the electron density distribution function in the analysis of the nature and estimation of the H-bond energies directly from experimental data are discussed. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 1–14, January, 2006.  相似文献   

3.
Single crystal XRD is used to study the crystal structure of 1-(4-bromobutyl)-3,6-dimethyluracil and 1,3-dimethyl-5-(5-bromopentyl)-isocyanurate in comparison with structurally similar compounds studied previously. It is shown that unlike macrocyclic compound, for which the crystal structure is determined by the presence of the stacking effect, in the crystals of their artificial precursors stacking interactions are not observed. For 1-(4-bromobutyl)-3,6-dimethyluracil, C-H...O interactions and C=O...Br interactions for 1,3-dimethyl-5-(5-bromopentyl)-isocyanurate are found. Original Russian Text Copyright ? 2009 by Yu. K. Voronina, L. F. Saifina, E. S. Romanova, O. A. Lodochnikova, and I. A. Litvinov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 3, pp. 608–611, May–June, 2009.  相似文献   

4.
An X-ray study of the crystals of bicyclic compounds containing fluorinated aromatic and nonfluorinated heteroaromatic rings, 5,6,7,8-tetrafluoroquinoline, 5,6,8-trifluoroquinoline, 5,7-difluoroquinoline, 5,7,8-trifluoro-2-phenylquinoline, and 5,7,8-trifluoro-6-trifluoromethylquinoline, was carried out. The basic supramolecular motifs and the underlying intermolecular interactions that control the lattice structure of these compounds were investigated. B3LYP DFT quantum-chemical calculations (6-311G(d,p) basis set) and the topological analysis of the electron density distribution in terms of Bader’s QTAIM theory were performed for the compounds. It is shown that the intermolecular interactions in question, traditionally regarded as nonvalent interactions, are related, to a definite extent, to the formation of very weak covalent chemical bonds in the intermolecular space due to the overlap of the “tails” of the molecular wave functions.  相似文献   

5.
利用甜菜碱衍生物1,5-二(4-羧基吡啶基)-N-甲基二乙胺(L)合成了两种镉(Ⅱ)的配位化合物[Cd2Cl4(H2O)2L2].2H2O和[Cd2(SCN)4(μ-H2O)L2]。用X-射线单晶衍射仪测定了配合物的单晶结构,并对它们进行了元素分析、红外光谱、1H NMR、热重等表征。结构分析表明,前者具有三十六元大环框架,而后者为双环结构。由于缺乏分子之间的强烈相互作用,弱相互作用决定了这两种化合物在晶格中的堆积模式:前者由相邻分子间的π-π和C-H…π相互作用而堆积形成二维砖墙的结构;后者由配位的SCN-阴离子通过S…S弱相互作用联接成一维链状结构。  相似文献   

6.
Summary Protonation of the sterically overcrowded N,N,N,N-tetraisopropyl-p-phenylenediamine leads to a significant shortening of the C-N bond lengths of 7 pm as well as to a widening of the phenyl ipso-angle to 122°. All structural changes can be attributed to the twisted diisopropylammonium substituents and their electron acceptor properties.
  相似文献   

7.
We have determined the crystal structures of two tetrachloridoaluminate salts. Tetrabutylammonium tetrachloridoaluminate benzene hemisolvate, (C16H36N)[AlCl4]·0.5C6H6, (I), crystallizes with discrete cations, anions and solvent molecules. The benzene molecule is located on a centre of inversion. The structure of the benzene‐free polymorph has been determined previously. Tetraethylammonium tetrachloridoaluminate, (C8H20N)[AlCl4], (II), also crystallizes with discrete cations and anions, and forms crystals which appear trigonal but are actually orthorhombic. With the additional reflections of the second and third domains of this nonmerohedral twin, a trigonal lattice is emulated, although the correct crystal system is orthorhombic.  相似文献   

8.
Four new oxygenated tricyclic diterpenoids have been isolated from the Caribbean brown alga Dictyota divaricata. The structures of these new compounds were secured by an X-ray analysis of a convenient diol derivative, followed by interconversion where possible. The new diterpenoids belong to the dolastane group first isolated from the herbivorous mollusc Dolabella auricularia and their isolation here indicates that the sea hare most likely derived these compounds from brown seaweeds of the family Dictyotaceae.  相似文献   

9.
Hydrogen bonds are considered a powerful organizing force in designing supramolecular architectures because they are directional, selective and reversible at room temperature. trans‐Dithiocyanatotetrakis(4‐vinylpyridine)nickel(II) is a popular host for the inclusion of small molecules and 2,3,5,6‐tetrafluoro‐1,4‐diiodobenzene (TFDIB) represents a strong halogen‐bond donor. These constituents cocrystallize in a 1:1 stoichiometry, [Ni(NCS)2(C7H7N)4]·C6F4I2, in the tetragonal space group I41/a. Both residues occupy special positions, i.e. the pseudo‐octahedral NiII complex is located on a twofold axis and the TFDIB molecule sits about a crystallographic centre of inversion. The components interact via a short S...I contact of 3.2891 (12) Å between the thiocyanate S atom of the host and the iodine substituent at the perhalogenated aromatic ring of the smaller guest molecule. This interaction meets the commonly accepted criteria for a halogen bond. Such halogen bonds to sulfur are significantly less common than to smaller electronegative atoms.  相似文献   

10.
Protonation of the [closo-3,3-(4-C10H12)-1-(CH2OH)-3,1,2-RhC2B9H10] PPN+ (C10H12 — dicyclopentadiene, PPN+ — bis(triphenylphosphine)iminium cation) at the ethylene bond of the norbornene moiety yields the neutralcloso-3,3,3-(-C10H13)-1-(CH2OH)-3,1,2-RhC2B9H10 with an agostic C-H...Rh bond. On prolonged storage in EtOH, the latter complex is converted intocloso-3,3-(3,2-C10H11)-1-(CH2OH)-3,1,2-RhC2B9H10 with -allylolefinic type coordination. Its crystal structure as dimeric aggregates with O-H...O and O-H...Rh bonds was determined by X-ray diffraction.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 776–778, April, 1995.  相似文献   

11.
A novel complex, chlorodi(p-chlorbenzyl)tin dithiotetrahydropyrrolocarbamate, has been synthesized. The crystal structure has been determined by X-ray single crystal diffraction. The crystal of the complex belongs to monoclinic with space group C2/c, a=3.070 0(19) nm, b=0.787 9(5) nm, c=2.374 9(15) nm, β=119.63(9) °, Z=8, V=4.993(5) nm3, Dc=1.515 g·cm-3, μ=1.521 mm-1, R1=0.047 4, wR2=0.097 2. The structure of the complex consists of discrete molecule containing five-coordinate tin atom in a seriously distorted trigonal bipyramidal configuration. The molecules are packed in the unit cell in one-dimensional chain polymer through a weak interaction between the chlorine atoms of the adjacent molecules. CCDC: 220743.  相似文献   

12.
Crystal structures resulting from a combination of different types of specific intermolecular interactions have been analysed using examples of 12 monohalogenated benzoic acids (HBA). These have been compared with structures known for corresponding monofunctional compounds, namely benzoic acid, fluorobenzene, chlorobenzene and iodobenzene. It is found that common for carboxylic acids centrosymmetric hydrogen-bonded dimers exist in all HBA, and at the same time a degree of halogen atoms aggregation is rather high in the most part of HBA, similarly to chlorobenzene and iodobenzene crystals. Previously reported tendency to increasing degree of Hal-aggregation in the sequence F < Cl ≤ Br ≤ I is confirmed. It is remarkable that a stacking motif of benzene rings is realised in all HBA crystals though it is absent in all considered monofunctional substances.  相似文献   

13.
The compound N,N′,N′′‐tricyclohexylphosphorothioic triamide, C18H36N3PS or P(S)[NHC6H11]3, (I), crystallizes in the space group Pnma with the molecule lying across a mirror plane; one N atom lies on the mirror plane, whereas the bond‐angle sum at the other N atom has a deviation of some 8° from the ideal value of 360° for a planar configuration. The orientation of the atoms attached to this nonplanar N atom corresponds to an anti orientation of the corresponding lone electron pair (LEP) with respect to the P=S group. The P=S bond length of 1.9785 (6) Å is within the expected range for compounds with a P(S)[N]3 skeleton; however, it is in the region of the longest bond lengths found for analogous structures. This may be due to the involvement of the P=S group in N—H...S=P hydrogen bonds. In O,O′‐diethyl (2‐phenylhydrazin‐1‐yl)thiophosphonate, C10H17N2O2PS or P(S)[OC2H5]2[NHNHC6H5], (II), the bond‐angle sum at the N atom attached to the phenyl ring is 345.1°, whereas, for the N atom bonded to the P atom, a practically planar environment is observed, with a bond‐angle sum of 359.1°. A Cambridge Structural Database [CSD; Allen (2002). Acta Cryst. B 58 , 380–388] analysis shows a shift of the maximum population of P=S bond lengths in compounds with a P(S)[O]2[N] skeleton to the shorter bond lengths relative to compounds with a P(S)[N]3 skeleton. The influence of this difference on the collective tendencies of N...S distances in N—H...S hydrogen bonds for structures with P(S)[N]3 and P(S)[O]2[N] segments were studied through a CSD analysis.  相似文献   

14.
13- and 26-Membered crown ethers have been synthesized based on resorcinol and 1,8-dichloro-3,6-dioxaoctane. The products with substituents in the benzene ring have been prepared by alkylation of 13-membered crown ether. Complexing properties of the macrocycles have been studied with the use of ion-selective membrane electrodes. The structures of 13- and 26-membered crown ethers have been established by X-ray structural analysis.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2458–2464, December, 1995.The work was supported by Technical University of Gdansk (Project DS No. 946197/003).  相似文献   

15.
Molecular mechanics calculations of geometric parameters and energies of molecular complexes with a O-H...M hydrogen bond have been performed for osmocene and decamethylosmocene with three proton donors. The results of calculations demonstrated that when rings are methylated, steric hindrances to formation of this hydrogen bond increase. This is the reason for anomalously low formation constants of H-bonded Cp 2 * M molecular associates compared to CP2M associates.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1925–1927, October, 1995.The work was supported by the Russian Foundation for Basic Research (Project No. 93-03-4610) and the International Science Foundation (Grant MP5 000).  相似文献   

16.
The title compound was crystallized from hot nitromethane. (18-crown-6) · 2CH3NO2 crystallizes in the monoclinic space groupP21/n witha=9.066(3),b=8.284(3),c=14.015(7) Å, =101.83(5)o andD calc=1.25 g cm–3 forZ=2. Least-squares refinement using 890 independent observed reflections led to a final conventionalR value of 0.084. The hydrogen atoms were located but not refined. The crown ether resides about a crystallographic center of invertion. There are two nitromethane molecules (one centered above and one below the crown ether) weakly interacting with the crown oxygen atoms via the methyl hydrogens stabilizing aD 3d crown conformation. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82029 (5 pages).  相似文献   

17.
The interaction energy of a [Au{C(NHMe)2}2]+ ... [Au{C(NHMe)2}2]+ dimer is investigated using the MP2 method and the LANL2DZ basis set when isolated or embedded in ionic an [Au{C(NHMe)2}2]2anion2 aggregate, a good model for the environment that these dimers feel in ionic crystals. A repulsive interaction energy is obtained when the dimer is isolated. However, it is possible to find short AuI ... AuI separations in [Au{C(NHMe)2}2]2anion2 aggregates, because in these aggregates the sum of the cation ... anion interactions overweight the sum of the cation ... cation plus anion...anion interactions. This explains why short AuI ... AuI separations are found in ionic crystals. The AuI ... AuI interaction found in [Au{C(NHMe)2}2]2 anion2 aggregates shows the same features observed in energetically stable dimers presenting AuI... AuI bonds. This makes appropriate to use the name counterion-mediated bonds for the AuI... AuI interactions found in [Au{C(NHMe)2}2]2 anion2 aggregates and ionic crystals.  相似文献   

18.
陈新  张明星  黄坤林 《结构化学》2012,31(11):1601-1607
A new metal-organic coordination polymer [Pb(mfpdc)(CH3OH)]n (1, mfpdc=2,6-dimethyl-4-(2-furanyl) pyridine-3,5-dicarboxylate) was synthesized and characterized by single-crystal X-ray analyses. The crystal is orthorhombic, space group Pbca, a=15.6297(18), b=9.4803(11), c=18.598(2), V=2755.8(6)3 , Z=8, Mr=498.44, Dc=2.403 Mg/m3 , F(000)=1872, the final R=0.0275 and wR=0.0726 (I>2 (I)). There are interesting polynuclear zigzag (PbO5 ) n chains in the structure of 1, and there have interesting axially chiral S-and R-unit Pb4L units constructed from prochiral organic ligands through C-H···O bonding. The (R/S)-Pb4L units by sharing Pb centers generate a 2-D coordination network, in which there exist rare π65 ···Pb(3.2610 ) interactions. The solid-state photoluminescent emission of compound 1 appears at 487 nm.  相似文献   

19.
SHAO Ying  QIN Lin  YUShu-Yan 《结构化学》2012,31(11):1545-1548
By employing functional ligand 3,6-bis(3,5-dimethyl-1H-pyrazol-4-yl)-9-methyl- 9H-carbazole, a novel luminescent Ni complex has been obtained. Its structure was characterized by single-crystal X-ray diffraction analysis. Crystal data: monoclinic, space group P2/c, a=13.4224(18), b=13.759(2), c=8.0633(17) , β=96.448(3)o, C23H23N5Ni(NO3)2 , Mr=552.19, V=1479.7(4)3 , Z=2, Dc=1.239 g/cm 3 , μ(MoKα)=0.700 mm -1 , F(000)=572, the final R=0.0566 and wR=0.1336 for 1638 observed reflections with I > 2σ(I). X-ray analysis indicates that each metal center coordinates with two N and two H atoms in tetrahedral interaction geometry. Weak interaction between Ni and N atom of pyrazole ligand and agostic bond (Ni···H-N interaction) play important roles in the formation of the 2-dimension framework. Significantly, this framework could pack into a tubular channel with NO3 - anions trapped inside.  相似文献   

20.
The title compounds were synthesized by the addition of AlMe3 to the corresponding azide suspended in an aromatic solvent. Both products were obtained as air-sensitive colorless crystals. Cs[Al2Me6N3]·2p-xylene crystallizes in the monoclinic space groupC2/m witha=19.143(6),b=16.227(6),c=10.392(5) Å, =114.06(2)o, and calc = 1.20 g cm–3 forZ=4. Refinement led to a conventionalR value of 0.037 for 2179 observed reflections. The cesium atom resides on a mirror plane, and the anion is disordered about a twofold axis. Thep-xylene molecules sandwich the cesium ion.[K·dibenzo-18-crown-6] [AlMe6N3]·1.5(1-methylnaphthalene) crystallizes in the monoclinic space groupP21/c witha=14.176(5),b=13.021(5),c=25.324(8) Å, =98.23(4)0, and calc = 1.08 g cm–3 forZ=4. The finalR value was 0.132 for 1402 observed reflections. One of the 1-methylnaphthalene molecules is disordered about a center of inversion and interacts with the potassium ion. The other solvent molecule is found roughly in layers in the lattice and also exhibits disorder of the methyl substituent. For both title compounds the AlMe3 groups of the anion exhibit a staggered (C s) conformation. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82015 (32 pages).  相似文献   

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