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1.
The crystal structures of three nitrated benzocrown ethers have been determined. Nitrobenzo-15-crown-5 crystallizes in the orthorhombic space group,Pca21, witha = 15.367(2),b = 4.8499(8),c = 19.963(5)Å, andD calc = 1.40 g cm–3 forZ = 4. Dinitrobenzo-15-crown-5 crystallizes in the monoclinic space group,P21/n, witha = 11.716(2),b = 8.495(3),c = 17.441(5)Å, = 108.40(2)° andD calc = 1.44 g cm–3 forZ = 4.Dinitrodibenzo-18-crown-6·2CH3CN ismonoclinic,P21/n,witha = 8.138(2),b = 20.435(9),c = 15.953(9)Å, = 100.55(4)° andD calc = 1.36 g cm–3 forZ = 4. The nitro substituents are in the plane of the benzo ring except in the sterically congested dinitrobenzo-15crown-5. The observed crown ether conformations are similar to their substituted analogs.For part 37, see reference [1].  相似文献   

2.
The synthesis and crystal structure of [Np(Urea)8]SiW12O40 · 2Urea · H2O complex are reported. Crystallographic parameters: space groups C2/c, a = 18.972(5) Å, b = 18.891(5) Å, c = 16.654(4) Å, = 100.847(6)°, Z = 4, V = 5862(3) Å3, (calcd) = 4.226 g/cm3. Thermal properties of this compound are studied; absorption spectra in the IR and visible regions are measured.  相似文献   

3.
Neptunium(V) perrhenate complex [(NpO2)(ReO4)(Phen)(H2O)2] was synthesized with 1,10-phenanthroline as a ligand. Its composition and structure were determined by X-ray diffraction analysis. The coordination polyhedron of the Np atom is a pentagonal bipyramid. The nearest surrounding of the neptunoyl ion includes the oxygen atom of the ReO4 anion, two nitrogen atoms of phenanthroline, and the oxygen atoms of two water molecules. The crystals of the compound are monoclinic. The main crystallographic parameters are the following: space group P21/c, unit cell parameters a = 7.288(1) Å, b = 10.513(2) Å, c = 20.936(4) Å, = 96.939(5)°, Z = 4, V = 1592.2(5) Å3. Absorption spectra of the compound in visible and IR regions are reported.  相似文献   

4.
Reactions of CsI and HgI2 with benzo-15-crown-5 (B15C5) and 15-crown-5 (15C5) in an ethanol-acetone mixture produced [Cs(B15C5)2]2[Hg2I6] (1) and {[Cs(15C5)]2[Hg2I6]}n (2), respectively. The structures of the two complexes are quite different. Molar ratios of Cs+ : crown ether are 1 : 2 in 1 and 1 : 1 in 2. Complex 1 consists of two Cs(B15C5) 2 + cations and a Hg2I 6 2- anion. Cs+ lies between the two crown-5 ligands, resulting in a sandwich-type cation. Cationic Cs(B15C5) 2 + and anionic Hg2I 6 2- are linked together by electrostatic interactions and the complex 1 is an ion pair compound. Complex 2 consists of infinite [Cs(15C5)]2[Hg2I6] units. Each structural unit contains two Cs(15C5)+ cations and a Hg2I 6 2- anion. Cs+ is coordinated by five oxygen atoms of 15C5, three iodine atoms of Hg2I 6 2- , and an iodine atom of Hg2I 6 2- in an adjacent structural unit. The interactions between the Cs+ of Cs(15C5)+ and an I in Hg2I 6 2- from adjacent structural units polymerize the complex 2, resulting in a one-dimensional network structure. The anions of Hg2I 6 2- in both complexes are similar. The two mercury atoms are linked through two bridging iodine atoms and each mercury is also coordinated by two terminal iodines. Crystal data for 1: space group P21/c (No. 14), a = 12.253(4), b = 20.945(7), c = 16.110(6) Å, = 111.0(1)°, V = 3860 Å3, Z = 4, R = 0.082 (R w = 0.089). Crystal data for 2: space group P21/c (No. 14), a = 12.157(4), b = 8.546(4), c = 20.666(6) Å, = 91.54(3)°, V = 2146 Å3, Z = 4, R = 0.034 (R w = 0.048).  相似文献   

5.
The interaction of K(35-Dnb) (35-Dnb=3,5-dinitrobenzoate) with benzo-15-crown-5 (B15C5) in ethanol yields a charge-separated sandwich structured complex [K(B15C5)2]+[35-Dnb(35-DnbH)2] even when equimolar amounts of reactants were used and no external 35-DnbH was added to the reaction mixture. The complex (KC49H51O28N6, FW=1211.1), is monoclinic,P21/c,a=11.063(2),b=10.680(1),c=46.548(8) Å, =91.629(2)0,Z=4,D 0=1.485 g/cm3,D c=1.468 g/cm3, CuK =1.5418 Å, =17.01 cm–1, 2<1300,F(000)=2520,T=298 K. FinalR for the 6618 observed reflections was 0.071. In the sandwich moiety, the K+ is 10-coordinated through all the oxygens of the crown molecules (K+–O, 2.76–3.11 Å). The 35-Dnb anion lies 5.3 Å below the lower crown mean plane and is charge separated with respect to K+ (K+–O>7 Å) but undergoes strong hydrogen bonding (2.59 and 2.49 Å) through each carboxylate oxygen with the carboxylic protons of two separate 35-DnbH molecules. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82014 (52 pages).  相似文献   

6.
Crystalline [Y(OH2)3(NCMe)(benzo-15-crown-5)][ClO4]3·benzo-15-crown-5-CH3CN can be obtained by slowly cooling a reaction mixture of Y(ClO4)3·n H2O with benzo-15-crown-5 in a solution of acetonitrile and methanol (3 : 1) from 60°C to room temperature. The crystal structure of this complex has been determined at –150 and 20°C. The complex is triclinic,P . At –150°C the cell parameters area = 11.986(4),b = 12.071(7),c = 16.364(5) Å, = 93.56(3), = 98.68(3), = 109.68(4)°, vol = 2187 Å3, andD calc = 1.61 g cm–3 forZ = 2 formula units. 3633 independently observed [F o 5(F o)] reflections were used in the final least-squares refinement leading to an agreement index ofR = 0.048. The Y(III) ion coordination geometry approximates a tricapped trigonal prism with three water molecules and three benzo-15-crown-5 oxygen atoms forming the prism, with the two remaining benzo-15-crown-5 oxygen atoms and the acetonitrile molecule completing the coordination as capping atoms. The three water molecules hydrogen bond a second crown ether molecule and two of the perchlorate anions. The two acetonitrile molecules have contacts with perchlorate oxygen atoms close enough for some weak interaction. One perchlorate is ordered, one is partially disordered as is the coordinated solvent molecule, and the third anion is totally disordered. The two unique crown ether molecules have distinctively different conformations.For Part 20, see reference [1].  相似文献   

7.
The interaction of barium with benzo-15-crown-5 (B15C5) has been followed under the competitive effect of various chelating organic anions (L), nitrophenolates and nitrobenzoates, in ethanol and ethanol-water (9:1). The rather heavily hydrated BaL2 salts yield novel 1:1 stoichiometric products in monohydrated or anhydrous states. Use of excess crown does not under any condition lead to the formation of 1:2 charge separated complexes, expected in view of the cavity and the cation sizes. The 1:1 Ba–B15C5 interaction is counteracted by L in accordance with its nucleophilicity, i.e., the pK a value of its parent acid, HL. The complex Ba(picrate)2(B15C5)·H2O (BaC26H26N6O20, FW=879.0), is monoclinic,P21/c,a=11.43(1),b=16.31(3),c=17.38(2) Å, =92.265(3)°,Z=4,D c=1.77 g/cm3,D 0=1.73 g/cm3, MoK, =0.71069 Å, 2 (4.0–50°), =13.5 cm–1,F(000)=1752,T=–32°C. FinalR for the 5926 reflections was 0.049. The structure reveals barium to be 10-coordinated through all the five crown oxygens (Ba–O, 2.800 to 3.002 Å), the two bidentate picrates (Ba–O, 2.642 and 2.666 Å; Ba–ONO, 2.825 and 2.994 Å), and the water molecule (2.711 Å) so that the cation constitutes a pseudo-sandwich of the crown on one side and the anionic species on the other. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82007 (50 pages). To obtain copies, see page ii of this issue.  相似文献   

8.
The crystal and molecular structures of the title host compound (I), C35H26O, and its inclusion complexes with water (II), C35H26O·H2O and dimethylsulphoxide (III), C35H26O·C2H6OS are reported. (I) is monoclinicC2/c,a = 9.725(1),b = 20.031(3),c = 26.545(3) Å, = 90.60(1)0,V = 5170 Å3,Z = 8; (II) is triclinic, ,a = 10.206(1),b = 10.324(2),c = 14.425(2) Å, = 101.68(1), = 89.92(2), = 116.34(1)0,V = 1327 Å3,Z = 2; (III) is monoclinicP21/n,a = 17.832(5),b = 10.109(3),c = 17.901(5) Å, = 111.93(2)0,V = 2993 Å3,Z =4. The structures were solved by direct methods and refined to final residuals of 0.045, 0.048, and 0.071, respectively. Thermal analysis of the complexes corroborates the crystallographic results.  相似文献   

9.
Complete structural characterization of dibenzo-18-crown-6·2 CH3NO2 and dibenzo-18-crown-6·2 CH3CN have been carried out, including location and refinement of the methyl hydrogen atoms. Dibenzo-18-crown-6·2 CH3NO2 is monoclinic,P21/c, with (at –150°C)a=9.573(2),b=14.636(2),c=33.471(7) Å, =93.77(2)°, andD calc=1.37 g cm–3 forZ=8. Interactions between the solvent methyl groups and the crown ethers and other solvent nitro groups associate the 1 : 2 complexes into polymeric chains alongb. The acetonitrile adduct exists as discreet 1 : 2 complexes in the solid state with C–H...O interactions exlusively to the ether. This complex is triclinic,P 1, with (at –150°C)a=9.458(6),b=9.570(5),c=14.404(5) Å, =73.18(4), =79.85(5), =66.82(6)°, andD calc=1.28 g cm–3 forZ=2. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82070 (22 pages).For part 4, see reference [1].  相似文献   

10.
The cluster [Cu4(S5)2(C5H5N)4]·S8 with cage structure has been obtained by reaction of copper powder with sulfur and K2S x in pyridine, and its structure was determined by X-ray crystallography. The crystal data for the title compound: triclinic, P (No. 2),Z = 2,a = 11.818(4) Å,b = 13.155(3) Å,c = 14.177(4) Å, = 93.79(2)°, = 96.68(2)°, = 115.76(2)°,V = 1954.52(1) Å3. The structure was refined toR = 0.038R w = 0.053) for 6444 data withI > 3.0(I).Dedicated to Professor Jiaxi Lu on the occasion of his 80th birthday.  相似文献   

11.
The crystal structures of two 12-membered crown ethers, benzo-12-crown-4 (1) and naphtho-12-crown-4 (2), have been determined by X-ray analysis. Both structures are molecular. Compound1 is monoclonic,P21/b,a=8.466(3),b=8.019(3),c=33.590(10) Å, =90.99(3)o. The unit cell contains two crystallographically independent molecules of1 with similar conformations. Compound2 is also monoclinic,P21/a,a=24.148(8),b=14.535(4),c=7.987(5) Å, =102.87(2)o. Two independent molecules in the unit cell have significantly different conformations. Supplementary data relating to this publication have been deposited with the British Library as Supplementary Publication No. SUP 82145 (19 pages).  相似文献   

12.
Single crystal X-ray analysis of a 1 : 2 complex between the dinaphthopyridino-l8-crown-6 host (1) and acetonitrile is reported. Crystals of the complex are monoclinic,P21/c witha = 12.178(5),b = 8.186(1),c = 30.873(1) Å, = 96.86(1)°, andD c = 1.25 g cm–3 forZ = 4. The host molecule reveals an approximate mirror symmetry and exists in a so-called dentist's chair conformation. One of the acetonitrile guest molecules is involved in possible weak interactions to two oxygen atoms of the host macroring, while the other fills free lattice space only.  相似文献   

13.
The molecular structures of (benzoyl)benzo-12-crown-4 (a=22.387,b=4.503,c=16.167 Å,d calc=1.34 g cm–3,Z=4, space groupP21 nc, DAR-UM, Cu-K,R=0.056) and (diphenylacetyl)benzo-12-crown-4 (a=8.866,b=23.337,c=10.737 Å;d calc=1.25 g cm–3,Z=4, space groupP212121, DAR-UM, Cu-K, R=0.056) have been investigated. The differences in the conformations of the macrocycles and the degree of conjugation between the benzene ring orbitals and the lone pairs on the adjacent oxygen atoms in the macrocycle are discussed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1906–1911, November, 1993.  相似文献   

14.
The decomposition of H2O BF3 in both the solid and solution states is rapid at room temperature, but 18-crown-6 H2O BF3,1, is stable to its melting point, 72°C.1 crystallizes in the monoclinic space groupC2/c witha = 27.273(9),b = 8.432(5),c = 22.936(9) Å, = 128.33(4)°, andD c = 1.27 g cm–3 forZ = 8. Least-squares refinement based on 1409 observed reflections led to a finalR = 0.083. The BF3 is covalently bonded to the oxygen atom of the water molecule which in turn is hydrogen bonded to the 18-crown-6.  相似文献   

15.
Abstract

The X-ray crystal structures of two closely related Ag(I) complexes of 15-crown-5 and benzo-15-crown-5 are reported. In the case of [Ag(15-crown-5)2][SbF6] 1, pointing one of its oxygen atoms away from the Ag+ cation enables one of the crown ligands to take part in an intermolecular C?H…O hydrogen bond. The analogous benzo-15-crown-5 species, [Ag(benzo-15-crown-5)2][SbF6] 2, is too rigid to attain the necessary conformation. Crystal data for 1: P21/c, a = 8.4481(3), b = 25.5813(9), c = 13.2773(4) Å, β = 101.354(2)°. Z = 4, unique data: 5187 R 1 [F 2 > 2σ(F 2)] 0.0259. Compound 2: P1, a = 8.6511 (15) Å, b =10.2322(18) Å, c = 19.291(3) Å, α = 103.704 (2)°, β = 101.274(2)°, γ = 95.952(2)°, Z = 2, unique data: 5803 R 1 [F 2>2σ(F 2)] 0.0931.  相似文献   

16.
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   

17.
Palladium clusters Pd4(SEt)4(OAc)4(I) and Pd6(SEt)12(II) were synthesized and studied. Their structure was determined by X-ray diffraction analysis. For I, a= 9.774(2) Å, b= 10.821(2) Å, c= 13.061(3) Å, = 92.88(3)°, V= 1379.6(5) Å3, (calcd.) = 2.182 g/cm3, space group P21/n, Z= 4, N ref= 1558, and R= 0.031; for II, a= 10.581(1) Å, b= 10.584(2) Å, c= 11.478(2) Å, = 101.62(1)°, = 104.95(1)°, = 106.74(1)°, V= 1135.2(4) Å3, (calcd) = 2.007 g/cm3, space group P1, Z= 1, N ref= 2828, and R= 0.022. In cluster I, four Pd atoms form a planar cycle. The neighboring palladium atoms are bound by two acetate or by two mercaptide bridges, the Pd···Pd distances being 3.036–3.195 Å. In cluster II, Pd atoms form a planar six-membered cycle with Pd···Pd distances of 3.083–3.127 Å. The neighboring palladium atoms are bound by two mercaptide bridges. The formation of analogous clusters in solution was confirmed by IR spectroscopy.  相似文献   

18.
The synthesis of the first liquid clathrate derived from an indium precursor is described. The aromatic/anion ratio of the inclusion complex prepared using benzene is 12.4. The use of toluene results in the inclusion of 10.3 guest toluene molecules/anion. The crystal structure of the parent complex, [K·18-Crown-6]2[InClI2(CH3)][InClI(CH3)2] was carried out. The compound belongs to the monoclinic space groupP21/c, witha=19.508(9),b=8.503(5), andc=29.437(9) Å, =96.55(3)°, andD calc=1.83 g cm–3 forZ=4. Least-squares refinement based on 3449 observed reflections led to a finalR=0.099. The structure displays two different environments for the two K+ cations in the asymmetric unit. One adopts the near-planar [K·18-crown-6]+ configuration while the other K+ resides 0.81 Å above the second 18-crown-6 plane. The latter K+ is apparently pulled out of the crown by a strong interaction with a Cl ion. Supplementary Data related to this article are deposited with the British Library as Supplementary Publication No. SUP 82046 (25 pages).  相似文献   

19.
The crystal structure of SnZrF6 is determined. The compound is synthesized by slow crystallization from a melted mixture of SnF2 and ZrF4 (2 : 1). The crystals are monoclinic: a = 6.6119(5), b = 5.2503(5), c = 6.9929(6) Å, = 114.239(4)°, space group P2/n, Z = 2. The structure is layered. The layers are formed from the chains of edge-sharing, eight-vertex zirconium polyhedra and Sn2+ cations. The Zr–F and Sn–F bond lengths in the layer vary from 2.309(1) to 2.269(1) Å and from 2.186(1) to 2.361(1) Å, respectively. The layers are linked by intermolecular Sn–F bonds with lengths of 2.868(1) and 2.871(1) Å.  相似文献   

20.
The crystal structure of (NpO2)(NO3)(CH3CONH2)2 was determined. The crystallographic data were are follows: a = 5.766(3) Å, b = 13.154(5) Å, c = 14.027(6) Å, V = 1064.0(8) Å3, space group Pnma, Z = 4, calcd = 2.804 g/cm3, R = 0.046, R w = 0.102. The coordination polyhedron of Np is a pentagonal bipyramid whose equatorial positions are occupied by the oxygen atoms of the neighboring NpO2 group, acetamide molecules, and of the nitrate ion. The IR and electronic absorption spectra of the compound were measured.  相似文献   

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