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101.
To further explore the coordination ability of an multi‐functional ligand 2‐(p‐bromophenyl)‐1H‐imidazole‐4,5‐dicarboxylic acid (p‐BrPhH3IDC), two metal‐organic frameworks [Mn(μ2‐p‐BrPhH2IDC)2]n ( I ) and {[Pb(μ2‐p‐BrPhH2IDC)2] · H2O}n ( II ) were synthesized under hydro(solvo)thermal conditions and structurally characterized by elemental analyses, IR spectroscsopy, and single‐crystal X‐ray diffraction. Polymer I shows a 2D sheet structure. In polymer II , 1D octagonal channels are connected by the organic ligands to form a 3D architecture. Furthermore, the thermal characteristics of the two polymers and the coordination features of p‐BrPhH3IDC were investigated. 相似文献
102.
三环己基氢氧化锡分别与辛二酸和壬二酸进行甲醇溶剂热反应,合成了2个双(三环已基锡)二元酸酯(CH2)n(CO2SnCy3)2[(n:6(1),7(2)],并用IR、1H和13C NMR、元素分析和X射线单晶衍射表征结构。化合物1、2均属单斜晶系,空间群分别为P21/n和P21/c,在化合物的晶体中,1通过Sn-O共价键,2通过Sn-O和Sn…O弱作用,分别形成了四锡核30元(1)和32元(2)二维大环网状结构。化合物1、2对人癌细胞Colo205、HepG2、MCF-7、Hela、NCI-H460均具有良好的体外抑制活性,对S. Aureus、B. Subtilis、E. Coli和S. Typhi具有选择性的抑菌作用。 相似文献
103.
Using the hydrothermal reactions of Mn(Ⅱ) and Ba(Ⅱ) salts with 2-(3-hydroxylphenyl)-1H-imidazole-4,5-dicarboxylic acid(m-OHPhH_3IDC),two novel metal-organic frameworks,namely,{[Mn(mOHPhHIDC)(H_2O)]2H_2O}_n(1) and {[Ba(m-OHPhH_2IDC)_2(H_2O)_3]-2H_2O)_n,(2) have been synthesized and structurally characterized by single-crystal X-ray crystallography,elemental analyses,and IR spectroscopy.Complex 1 features a novel non-interpenetrated three-dimensional(3,4)-connected network with one-dimensional open channels.Complex 2 exhibits a two-dimensional layered structure with rhombic grids.The role of the central metals in the formation of final architectures has been discussed.Furthermore,luminescent and thermal properties of the two complexes have been studied. 相似文献
104.
Guo-Qing Shi Yong-Chao Zhu Jing Wang Zong-Can Ren 《Journal of Coordination Chemistry》2016,69(14):2231-2246
Four metal-organic frameworks, [Sr(o-ClPhHIDC)(H2O)2]n (o-ClPhH3IDC = 2-(o-chlorophenyl)-1H-imidazole-4,5-dicarboxylic acid) (1), [Mg(m-ClPhHIDC)(H2O)2]n (2), [Sr(m-ClPhHIDC)(H2O)]n (3) and {[Co3(m-ClPhIDC)2(H2O)6]·2H2O}n (m-ClPhH3IDC = 2-(m-chlorophenyl)-1H-imidazole-4,5-dicarboxylic acid) (4), have been solvothermally synthesized and structurally characterized. Single-crystal X-ray analyses reveal that 1–3 show 2-D architectures and 4 exhibits a 3-D structure. The o-ClPhH3IDC and m-ClPhH3IDC ligands in the polymers can be partly deprotonated and coordinate to metal ions by various modes. The metal ions of 1–4 are coordinated only to oxygens. The thermal and luminescence properties of the polymers have also been investigated. 相似文献
105.
Qiu-Ying Huang Xiao-Yi Lin Xiang-Ru Meng 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(6):480-484
The N‐heterocyclic ligand 2‐[(1H‐imidazol‐1‐yl)methyl]‐1H‐benzimidazole (imb) has a rich variety of coordination modes and can lead to polymers with intriguing structures and interesting properties. In the coordination polymer catena‐poly[[cadmium(II)‐bis[μ‐benzene‐1,2‐dicarboxylato‐κ4O1,O1′:O2,O2′]‐cadmium(II)‐bis{μ‐2‐[(1H‐imidazol‐1‐yl)methyl]‐1H‐benzimidazole}‐κ2N2:N3;κ2N3:N2] dimethylformamide disolvate], {[Cd(C8H4O4)(C11H10N4)]·C3H7NO}n, (I), each CdII ion exhibits an irregular octahedral CdO4N2 coordination geometry and is coordinated by four O atoms from two symmetry‐related benzene‐1,2‐dicarboxylate (1,2‐bdic2−) ligands and two N atoms from two symmetry‐related imb ligands. Two CdII ions are connected by two benzene‐1,2‐dicarboxylate ligands to generate a binuclear [Cd2(1,2‐bdic)2] unit. The binuclear units are further connected into a one‐dimensional chain by pairs of bridging imb ligands. These one‐dimensional chains are further connected through N—H…O hydrogen bonds and π–π interactions, leading to a two‐dimensional layered structure. The dimethylformamide solvent molecules are organized in dimeric pairs via weak interactions. In addition, the title polymer exhibits good fluorescence properties in the solid state at room temperature. 相似文献
106.
Li-Juan Zhou Chang-Bao Han Yu-Ling Wang 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(2):133-138
Coordination polymers constructed from metal ions and organic ligands have attracted considerable attention owing to their diverse structural topologies and potential applications. Ligands containing carboxylate groups are among the most extensively studied because of their versatile coordination modes. Reactions of benzene‐1,4‐dicarboxylic acid (H2BDC) and pyridine (py) with ZnII or CoII yielded two new coordination polymers, namely, poly[(μ4‐benzene‐1,4‐dicarboxylato‐κ4O:O′:O′′:O′′′)(pyridine‐κN)zinc(II)], [Zn(C8H4O2)(C5H5N)]n, (I), and catena‐poly[aqua(μ3‐benzene‐1,4‐dicarboxylato‐κ3O:O′:O′′)bis(pyridine‐κN)cobalt(II)], [Co(C8H4O2)(C5H5N)2(H2O)]n, (II). In compound (I), the ZnII cation is five‐coordinated by four carboxylate O atoms from four BDC2− ligands and one pyridine N atom in a distorted square‐pyramidal coordination geometry. Four carboxylate groups bridge two ZnII ions to form centrosymmetric paddle‐wheel‐like Zn2(μ2‐COO)4 units, which are linked by the benzene rings of the BDC2− ligands to generate a two‐dimensional layered structure. The two‐dimensional layer is extended into a three‐dimensional supramolecular structure with the help of π–π stacking interactions between the aromatic rings. Compound (II) has a one‐dimensional double‐chain structure based on Co2(μ2‐COO)2 units. The CoII cations are bridged by BDC2− ligands and are octahedrally coordinated by three carboxylate O atoms from three BDC2− ligands, one water O atom and two pyridine N atoms. Interchain O—H…O hydrogen‐bonding interactions link these chains to form a three‐dimensional supramolecular architecture. 相似文献
107.
In this paper, three luminescent metal–organic frameworks, namely: [Zn(p-IPhHIDC)]n (1), {[Cd(p-IPhIDC)(H2O)]·CH3OH}n (2) and [Zn(p-TIPhHIDC)]n (3), bearing two novel substituted imidazole dicarboxylate ligands, 2-(p-N-imidazol-1-yl)-phenyl-1H-imidazole-4,5dicarboxylic acid (p-IPhH3IDC) and 2-p-(1H-1,2,4-triazol-1-yl)-phenyl-1H-imidazole-4,5dicarboxylic acid (p-TIPhH3IDC), have been prepared and characterised through infrared spectra, X-ray powder diffraction, elemental analyses, thermogravimetric analyses and single-crystal X-ray diffraction. Ignoring the free methanol molecule and coordinated water in 2, 1–3 are similar structures. Moreover, the luminescent properties of the MOFs have been explored. It was found that MOFs 1 and 2 show good luminescent sensing of Fe3+ in varying degrees, and 3 of K+. 相似文献
108.
Yongfeng Yang Tao Li Yanmei Chen 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(10):903-907
The title compound, poly[[diaqua‐1κ2O‐tetrakis(μ3‐pyridine‐2,3‐dicarboxylato)‐2:1:2′κ10N,O2:O2′,O3:O3′;2:1:2′κ8O3:O3′:N,O2‐diiron(III)strontium(II)] dihydrate], {[Fe2Sr(C7H3O4)4(H2O)2]·2H2O}n, which has triclinic (P) symmetry, was prepared by the reaction of pyridine‐2,3‐dicarboxylic acid, SrCl2·6H2O and Fe(OAc)2(OH) (OAc is acetate) in the presence of imidazole in water at 363 K. In the crystal structure, the pyridine‐2,3‐dicarboxylate (pydc2−) ligand exhibits μ3‐η1,η1:η1:η1 and μ3‐η1,η1:η1,η1:η1 coordination modes, bridging two FeIII cations and one SrII cation. The SrII cation, which is located on an inversion centre, is eight‐coordinated by six O atoms of four pydc2− ligands and two water molecules. The coordination geometry of the SrII cation can be best described as distorted dodecahedral. The FeIII cation is six‐coordinated by O and N atoms of four pydc2− ligands in a slightly distorted octahedral geometry. Each FeIII cation bridges two neighbouring FeIII cations to form a one‐dimensional [Fe2(pydc)4]n chain. The chains are connected by SrII cations to form a three‐dimensional framework. The topology type of this framework is tfj . The structure displays O—H...O and C—H...O hydrogen bonding. 相似文献
109.
One novel 1D polymer, [Cd2(m-BrPhHIDC)2(4,4′-bipy)(H2O)2]n (1) (m-BrPhH3IDC = 2-(3-bromophenyl)-1H-imidazole-4,5-dicarboxylic acid; 4,4′-bipy = 4,4′-bipyridine), has been hydrothermally synthesised and characterised by single-crystal X-ray diffraction, elemental analysis, IR, powder X-ray diffraction (PXRD) and thermogravimetric analysis. Polymer 1 composed of tetranuclear square [Cd2(m-BrPhHIDC)2] second building units and 4,4′-bipy bridges shows the interesting tunable luminescence properties aroused by pyridine. A luminescence enhance mechanism has been proposed. 相似文献
110.
C. Hakme I. Stevenson A. Voice G. Lespinasse G. Seytre L. David 《Journal of Polymer Science.Polymer Physics》2007,45(15):1950-1958
Poly(ethylene naphthalene‐2,6‐dicarboxylate) has been uniaxially stretched at different draw ratios and at two different temperatures below and above its glass transition (Tg ~ 120 °C) respectively, at 100 and 160 °C. Crystallinity has been evaluated from calorimetric analyses and compared to the values deduced by FTIR spectroscopic data. As expected, the obtained results are quite similar and show that films stretched at lower temperature (100 °C) are more crystalline than those stretched at 160 °C. Optical anisotropy associated with orientation has been evaluated by birefringence and show that films stretched at 100 °C are more birefringent than those stretched at 160 °C as a result of a higher chain relaxation above Tg. Polarized FTIR was also performed to evaluate the individual orientation of amorphous and crystalline phases by calculating dichroic ratios R and orientation functions 〈P2(cos θ)〉 and also show that amorphous and crystalline phases are more oriented in the case of films stretched below Tg. Nevertheless, the orientation of the amorphous phase is always weaker than that of the crystalline phase. Films stretched at 100 °C show a rapid increase in orientation (and crystallinity) with draw ratio and 〈P2(cos θ)〉 reaches a limit value when draw ratio becomes higher than 3.5. Films drawn at 160 °C are less oriented and their orientation is increasing progressively with draw ratio without showing a plateau. A careful measurement of the IR absorbance was necessary to evaluate the structural angles of the transition moments to the molecular chain axis. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1950–1958, 2007 相似文献