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21.

Abstract  

Two imidazolyl derived complexes [N,N′-butylenebis(imidazole): (fumaric acid)2 (1), and N,N′-butylenebis(imidazole): (2,4,6-trinitrophenol)2 (2)] were prepared and structurally characterized by X-ray crystallography. Compound 1 crystallizes in the triclinic, space group P−1, with a = 5.9990(12) ?, b = 8.1772(16) ?, c = 10.419(2) ?, α = 86.88(2)°, β = 84.73(3)°, γ = 77.03(4)°, V = 495.67(17) ?3, Z = 1. For 1, two dimensional network structure is formed through imidazolium moieties forming hydrogen bonds to di-ionic carboxylate groups of fumarate chains. In the same network layers and adjacent layers, C–H···O contact also accompanies the N+–H···O hydrogen bonds, all these lead the extended architecture to show a three-dimensional lamellar structure. Compound 2 crystallizes in the triclinic, space group P − 1, with a = 7.0236(14) ?, b = 8.2831(17) ?, c = 12.053(2) ?, α = 106.05(4)°, β = 99.13(2)°, γ = 98.84(3)°, V = 650.8(2) ?3, Z = 1. In 2, two parallel imidazolium cations and two antiparallel 2,4,6-trinitrophenolate anions formed 32-membered rings through hydrogen bonding interaction, these rings extended along the c axis direction to form one dimensional railway structure. Adjacent parallel railways connect further through C–H···O hydrogen bonds between the 2-CH of the imidazole ring and the NO2 group O atoms. These weak interactions combined, the complex showed 3D layer structure.  相似文献   
22.
A series of organotin (IV) complexes with 6-amino-1,3,5-triazine-2,4-dithiol of the type [(RnSnCl4−n)2 (C3H2N4S2)] (n = 3: R = Me 1, n-Bu 2, PhCH23, Ph 4; n = 2: R = Me 5, n-Bu 6, PhCH27, Ph 8) have been synthesized. All the complexes 1-8 have been characterized by elemental analysis, IR, 1H and 13C NMR spectra. Among them complexes 1, 4, 5 and 8 have also been characterized by X-ray crystallography diffraction analyses, which revealed that the tin atoms of complexes 1, 4, 5 and 8 are all five-coordinated with distorted trigonal bipyramid geometries.  相似文献   
23.
A 2,2'-[2,3-naphthylenebis(oxy)]-bis(N,N-diisopropyl(acetamide)) ligand (L) and its Gd(III) complex have been prepared and characterized. The crystal and molecular structure of the complex was determined by single-crystal X-ray diffraction. The interactions of complex with calf thymus DNA were investigated by UV-vis, fluorescence and viscosity measurements. Experimental results indicated that the complex can bind to DNA by intercalation modes. Its intrinsic binding constant is 1.03 x 10(6) M(-1).  相似文献   
24.
In the title coordination compound, catena‐poly[[[bis[diaquacadmium(II)]‐μ2trans‐1,2‐bis(4‐pyridyl)ethene]bis{μ2‐2,2′‐[(5‐carboxymethoxy‐m‐phenylene)dioxy]diacetato}] trans‐1,2‐bis(4‐pyridyl)ethene solvate dihydrate], {[Cd2(C12H10O9)2(C12H10N2)(H2O)4]·C12H10N2·2H2O}n, (I), each CdII centre adopts a pentagonal–bipyramidal coordination geometry. The incompletely deprotonated 2,2′‐[(5‐carboxymethoxy‐m‐phenylene)dioxy]diacetate (TCMB) ligands and trans‐1,2‐bis(4‐pyridyl)ethene (bpe) ligands both act as bidentate bridges, linking the CdII centres into one‐dimensional ladders, which are connected into an undulating two‐dimensional (6,3) layer through O—H...N hydrogen bonds between the carboxylate groups of the TCMB ligands and the N atoms of the uncoordinated bpe ligands. Each undulating layer polycatenates two other identical layers, exhibiting the unusual combination of both 2D → 2D parallel and 2D → 3D parallel interpenetration (2D and 3D are two‐ and three‐dimensional, respectively).  相似文献   
25.
Reaction of tri(o-fluorobenzyl)tin chloride with sodium of heteroaromatic carboxylic acid in 1:1 stoichiometry yielded complexes of the type (2-F-Bz)3SnOOCR (R=2-furanyl, 2-furanvingl, 2-thiophenyl, 2-pyridinyl, 3-pyridinyl, 4-pyridinyl, 3-indolyl, 3-indolmethyl and 3-indolpropyl), respectively. These complexes have been characterized by elemental analyses, IR and 1H NMR spectroscopy. The crystal structures of tri(o-fluorobenzyl)tin esters of 4-pyridinecarboxylic acid (5) and 3-pyridinecarboxylic acid (6) were determined by single crystal X-ray diffraction. In the crystals of compounds 5 and 6, the tin atoms are rendered five-coordinate in a trigonal bipyramidal structure by coordinating with pyridine N atom of carboxylate group. The resulting structure is a one-dimensional linear polymer containing Sn-O bond lengths of 2.161(4), 2.202(9) Å and Sn-N bond lengths of 2.518(5), 2.454(10) Å.  相似文献   
26.
A novel compound (NH4)2Y(H2O)8[PMo10V2O40]·10H2O has been prepared in an aqueous solution and characterized by elemental analysis, IR, and TG-DTG analysis. X-ray diffraction analysis was carried out on (NH4)2Y(H2O)8 [PMo10V2O40]·10H2O single crystal, which crystallizes in the monoclinic system of a space group P21/c witha=0. 9871 (3) nm,b=1. 5424 (5) nm,c=2.7924(9) nm, β = 94.183(5)° and Z=2. In the compound, a two-dimensional network is constructed by the PMo10V2O 40 5? anion and the Y(H2O) 8 3+ cation building blocks via hydrogen bonding exhibiting the porous structure.  相似文献   
27.
用4,5-二氮芴-9-酮(dafo)、邻苯二甲酸和硝酸铜合成了二价铜的一维链状超 分子化合物[Cu(dafo)_2(H_2O)_2]-(OPA)_2(OPA=邻苯二甲酸一价阴离子),其结构 通过单晶X射线衍射法确定。该化合物是单斜晶系,空间群为P2(1)/c。晶胞参数: a = 0.71093(16)nm, b = 1.5724(4)nm, c = 1.5357(3)nm, α=90.000(5) °, β =102.220(4) °,γ=90.000(5) °, V = 1.6778(6)nm~3, Z = 2, F(000) = 814, M_r = 794.17, D_c = 1.527 g/cm~3, μ = 0.727 mm~(-1), R_1 = 0.0406, wR_2 = 0.0930.单晶结构分析表明该化合物具有一维链状结构,该结构是通过氢 键这种弱相互作用形成的。  相似文献   
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