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11.
张锦  陈宏基  黄晶 《结构化学》2011,30(7):1069-1073
The title compound,[Zn(5-hydroxynicotinate) 2 2H 2 O] n,has been synthesized by reacting zinc sulfate vitriol with 5-hydroxynicotinic acid under hydrothermal conditions,and its structure was determined by X-ray crystallography with the following data:monoclinic,space group C2/c,C 12 H 12 N 2 O 8 Zn,M r=377.61,a=10.223(3),b=10.319(3),c=13.613(4),β=105.922(6)°,Z=4,V=1380.9(8)3,F(000)=768,D c=1.816 g/cm 3,μ(MoKα)=1.826 mm-1,the final R=0.0401 and wR=0.1380 for 1157 observed reflections (I > 2σ(I)).In the structure of the title compound,the Zn II ion located in an inversion center lies in a distorted tetrahedral environment at a N 2 O 2 coordination mode,and the 5-hydroxynicotinic acid ligand links symmetry-related Zn II ions at a μ 2-N,O bridging way forming a two-dimensional covalent structure.In the crystal,solvent water molecules form intermolecular O-H O hydrogen bonds and pyridine rings of adjacent layers form π-π stacking (3.346),which connect adjacent two-dimensional sheets into a three-dimensional supramolecular network.  相似文献   
12.
A vanadyl phosphate containing a new member of tancoite-like single chain, (DAPH2)[VIVO(HPO4)2]·xH20 (x ≈ 0.2, DAP = 1,3-diaminopropane, C3H10N2), has been synthesized under hydro(solvo)thermal conditions. It crystallizes in orthorhombic space group P21212 (No. 18) with a = 7.1730(14), b = 19.252(4), c = 8.6557(17) A, Z= 4, V= 1195.3(4)A3, C3H14.38N2P2VO9.19, Mr = 338.47, Dc = 1.881 g/cm3,μ(MoKa) = 1.138 mm-1 and F(000) = 692. The final full-matrix least-squares refinement converged to R = 0.0408, wR = 0.1046 for 2498 observed reflections with I 〉 2σ(I) and R = 0.0456 and wR = 0.1080 for all data (2750) and S = 1.001. Its one-dimensional 1 structure consists of tancoite-like ∞1 {vIVO(HPO4)2}2- single chains surrounded by DAPH22+ ions and water molecules. The single chain is built from trans-corner-sharing octahedral {VIV= O…VIV} backbone loop-branched by HPO4 groups like staple forming a new member of tancoite single chain. Due to the special coordination of VIVO6, the ∞1 {VO(HPO4)2-} chain adopts a larger M-O-M angle (V-O-V = 135°) than those of tancoite chains reported before. The corner-sharing linear {VIV = O…VIV} chain structure also leads to a one-dimensional weak antiferromagnetic interaction at low temperature. The magnetic measurements confirm the 4+ valence state of vanadium. IR and TG results of the title compound are also discussed.  相似文献   
13.
A new compound [CpCo(Se2C2BIoH9)CH2C(O)C4H30] has been synthesized and characterized by elemental analysis, IR spectroscopy, NMR, MS and single-crystal X-ray diffraction. The complex crystallizes in the monoclinic system, space group P21/c with a = 10.9481(10), b = 24.6600(12), c = 25.7430(14) A, β = 100.863(3)°, C42H57B30Co306Se6"CH2C12"0.25H20, Mr = 1722.16, V = 6825.6(8) A3, Dc= 1.676 g/cm3, Z = 1 and F(000) = 3346. The molecular structure shows a 1:1 ratio product of the two reactants of 16e half-sandwich complex CpCo(Se2C2B10H10) and alkyne 1-(2-furyl)-2-propyn-l-one. The hydrogen atom in the B(3) position of CpCo(Se2C2B10HIo) has been activated and migrated to the terminal carbon of 1-(2-furyl)- 2-propyn-l-one to form the B-CH2 unit. The title compound molecules are linked and extended further into a one-dimensional chain through atypical hydrogen bonds.  相似文献   
14.
15.
<正>本刊是宁波大学主办的综合性自然科学和工程技术学术期刊,创刊于1988年,现为季刊,国内外公开发行.主要刊登理、工、农、林、医等学科的学术论文和研究成果,欢迎本校师生和关心宁波大学建设的各方学人来稿.1投稿要求1.1文稿书写要求:文章论点明确、论据充分、层次分明,文字简练,图表清晰,文稿篇幅(含图表)一般在8000字以内.1.2文稿书写顺序:中文标题;作者姓名;作者单位;中文摘要(要有目的、方法、结果、结论 4要素内容,200字左右);中文关键词(3~5个,用分号隔开);中图分类号(按《中国图书馆分类法》(第4版)标引);  相似文献   
16.
The title compound (C16H15ClN2) has been synthesized by a facile self-condensation of o-tolunitrile promoted by potassium tert-butanolate in DMPU, and its structure was characterized by ^1H NMR, ^13C NMR, IR, UV, HRMS and X-ray single-crystal diffraction. The crystal belongs to orthorhombic, space group Pna21 with a = 19.560(3), b = 7.8500(14), c = 18.428(3) A^°, Dc = 1.271 g/cm^3, Z= 8, 2 = 0.71073 A^°,μ(MoKa) = 0.257 mm^-1, Mr = 270.75, V= 2829.5(8) A^°^3, Flack parameter = 0.12(12), F(000) = 1136, the final R = 0.0571 and wR = 0.1445 for 2701 observed reflections with I 〉 20(I). The intermolecular N-H…Cl hydrogen bonds link the molecules into a one-dimensional chain running along axis a.  相似文献   
17.
2-(4-Decarboxydehydroabietyl)-5-p-toyl-[1,3,4]-oxadiazole, C28H34N2O, has been synthesized and characterized by IR, NMR, elemental analysis and single-crystal X-ray diffraction method. The crystal belongs to the orthorhombic system, space group P212121 with a = 6.1351(5), b = 14.8495(19), c = 25.9050(2) A, V = 2360.0(4) A3, Z = 4, Mr = 414.57, Dc = 1.167 Mg/m^3, 2 = 0.71073 A,μ(MoKa) = 0.070 mm^-1, F(000) = 896, the final R = 0.0452 and wR = 0.1076 for 1647 observed reflections with I 〉 2σ(I). There are five rings in the crystal structure of the title compound, but the oxadiazole ring is non-coplanar with the benzene ring D.  相似文献   
18.
The title compound 4-(2-bromophenyl)-3,4,7,8-tetrahydro-7,7-dimethyl-1-p-tolylquinoline-2,5(1H,6H)-dione 1 (C24H24BrNO2, Mr = 438.35) was synthesized and characterized by IR, 1H NMR and elemental analysis. The crystal belongs to monoclinic, space group C2/c with a = 27.565(14), b = 10.079(5), c = 15.917(8) A,β = 111.059(9)°, Z = 8, V = 4127(4)A3, Dc = 1.411 g·cm^-3,μ(MoKa) = 2.011 mm^-1, F(000) = 1808, the final R = 0.0417 and wR = 0.1032 for 2393 observed reflections (I 〉 2σ(I)). X-ray analysis reveals that the pyridine ring adopts a distorted boat conformation, while another six-membered ring takes a half-chair conformation. In addition, there are non-classical hydrogen bonds of C-H…O and C-H…Br in the structure. The short distance (3.481A) between the adjacent 2-bromophenyl rings indicates the existence of π-π interaction.  相似文献   
19.
段文增  冯帅  孙斌  吴仁涛 《结构化学》2009,28(10):1290-1295
The title compound [2-(2,6-dioxacyclohexyl)-5-methoxylphenols]2 was synthesized by the reaction of 2-hydroxyl-3-methoxylbenzaldehyde and 1,3-propanediol in the presence of DMF-DMS adduct and characterized by IR spectrum, UV-Vis spectrum and X-ray crystallography. The title compound belongs to monoclinic, space group P21 with a = 9.8967(10), b = 8.2240(9), c = 13.3654(14) A^°, β= 90.016(2)°, C11H14O4, Mr = 210.22, V = 1087.8(2)A^°3, Z = 4, Dc = 1.284 Mg/m^3, F(000) = 448,μ = 0.098 mm^-1, the final R = 0.0300 and wR = 0.0761 for 2070 observed reflections with I 〉 2σ(I). The molecules are connected via intermolecular O-H…O hydrogen bonds into a 2D network structure. Moreover, theoretical investigations of the title compound with HF/6-31G(d) method were performed, and its stability, frontier molecular orbital composition and Mulliken charge distribution were also discussed. The compound is a bis-molecule. The two molecules stay together and could not be separated. Two crystallographically independent molecules exist in an asymmetric unit. The bond lengths and bond angles of the two molecules are slightly different with each other.  相似文献   
20.
The title complex, C20H17N4Pd2Cl3·0.5CH3OH, crystallizes in the triclinic system, space group P1 with a = 9.927(6), b = 11.079(6), c = 11.233(6) ?, α = 73.970(12), β = 85.738(16), γ = 83.300(12)o, V = 1178.1(11)?3, Mr = 648.55, Z = 2, Dc = 1.520 g/cm3, μ = 1.884 mm-1, F(000) = 634, the final R = 0.0460 and wR = 0.1280. This title compound was investigated for the catalytic behavior towards norbornene(NB) vinyl addition polymerization. And the complex exhibits good catalytic activity to catalyze norbornene polymerization using MAO as a cocatalyst.  相似文献   
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