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41.
In the construction of coordination polymers, many factors can influence the formation of the final architectures, such as the nature of the metal centres, the organic ligands and the counter‐anions. In the coordination polymer poly[aqua(μ‐benzene‐1,2‐dicarboxylato‐κ4O 1,O 1′:O 2,O 2′)[μ‐2‐(1H‐imidazol‐1‐ylmethyl)‐6‐methyl‐1H‐benzimidazole‐κ2N 2:N 3]cadmium(II)], [Cd(C12H12N4)(C8H4O4)(H2O)]n or [Cd(immb)(1,2‐bdic)(H2O)]n , each CdII ion is seven‐coordinated by two N atoms from two symmetry‐related 2‐(1H‐imidazol‐1‐ylmethyl)‐6‐methyl‐1H‐benzimidazole (immb) ligands, by four O atoms from two symmetry‐related benzene‐1,2‐dicarboxylate (1,2‐bdic2−) ligands and by one water molecule, leading to a CdN2O5 distorted pentagonal bipyramidal coordination environment. The immb and 1,2‐bdic2− ligands bridge CdII ions and form a two‐dimensional network structure. O—H…O and N—H…O hydrogen bonds stabilize the structure. In addition, the IR spectroscopic properties, PXRD patterns, thermogravimetric behaviour and fluorescence properties of the title polymer have been investigated.  相似文献   
42.
Subtle modifications of N‐donor ligands can result in complexes with very different compositions and architectures. In the complex catena‐poly[[bis{1‐[(1H‐benzotriazol‐1‐yl)methyl]‐1H‐imidazole‐κN 3}copper(II)]‐μ‐benzene‐1,3‐dicarboxylato‐κ3O 1,O 1′:O 3], {[Cu(C8H4O4)(C10H9N5)2(H2O)]·2H2O}n , each CuII ion is six‐coordinated by two N atoms from two crystallographically independent 1‐[(1H‐benzotriazol‐1‐yl)methyl]‐1H‐imidazole (bmi) ligands, by three O atoms from two symmetry‐related benzene‐1,3‐dicarboxylate (bdic2−) ligands and by one water molecule, leading to a distorted CuN2O4 octahedral coordination environment. The CuII ions are connected by bridging bdic2− anions to generate a one‐dimensional chain. The bmi ligands coordinate to the CuII ions in monodentate modes and are pendant on opposite sides of the main chain. In the crystal, the chains are linked by O—H…O and O—H…N hydrogen bonds, as well as by π–π interactions, into a three‐dimensional network. A thermogravimetric analysis was carried out and the fluorescence behaviour of the complex was also investigated.  相似文献   
43.
The imidazole‐based dicarboxylate ligand 2‐(4‐(pyridin‐4‐yl)phenyl)‐1H‐imidazole‐4,5‐dicarboxylic acid (H3PyPhIDC), was synthesized and its coordination chemistry was studied. Solvothermal reactions of CaII, MnII, CoII, and NiII ions with H3PyPhIDC produced four coordination polymers, [Ca(μ3‐HPyPhIDC)(H2O)2]n ( 1 ), {[M32‐H2PyPhIDC)23‐HPyPhIDC)26(H2O)2] · 6H2O}n [M = Mn ( 2 ), Co ( 3 )], and {[Ni(μ3‐HPyPhIDC)(H2O)] · H2O}n ( 4 ). Compounds 1 – 4 were analyzed by IR spectroscopy, elemental analyses, and single‐crystal and powder X‐ray diffraction. Compound 1 displays a one‐dimensional (1D) infinite chain. Compounds 2 and 3 are of similar structure, showing 2D network structures with a (4,4) topology based on trinuclear clusters. Compound 4 has another type of 2D network structure with a 3‐connected (4.82) topology. The results revealed that the structural diversity is attributed to the coordination numbers and geometries of metal ions as well as the coordination modes and conformations of H3PyPhIDC. Moreover, the thermogravimetric analyses of all the compounds as well as luminescence properties of the H3PyPhIDC ligand and compound 1 were also studied.  相似文献   
44.
By employing 2-(4-methoxyphenyl)-1H-imidazole-4,5-dicarboxylic acid (p-MOPhH3IDC) to react with Cd(II), Zn(II) and Sr(II) ions, four polymers, [Cd(p-MOPhHIDC)(2,2′-bipy)]n (2,2′-bipy = 2,2′-bipyridine) (1), [Zn0.5(p-MOPhH2IDC)·H2O]n (2), {[Cd4(p-MOPhHIDC)4(C2H5OH)2(H2O)2]·4C2H5OH·2H2O}n (3) and {[Sr2(H2MOPhIDC)2(C8H4O4)(H2O)6]·6H2O}n (4) have been solvothermally synthesised and structurally characterised by single-crystal X-ray diffraction. Polymer 1 is a chain with 2,2′-bipy appending in the same side. Polymer 2 is a 2D rhombus grid structure. The π?π interactions between the aromatic groups supply the additional stabilisation for the solid-state structures of 1 and 2. Polymer 3 shows a 3D framework bearing 1D open channels. Polymer 4 exhibits a 2D latticed plane. The thermal and photoluminescence properties of 14 have been investigated as well.  相似文献   
45.
氧化双[三(2-甲基-2-苯基)丙基]锡分别与庚二酸和辛二酸反应, 合成了2个双[三(2-甲基-2-苯基)丙基锡]二元酸酯(CH2)n[CO2Sn(CH2CMe2Ph)3]2[(n=5 (1), 6 (2)], 经IR、1H和13C NMR、元素分析和X射线单晶衍射对化合物进行了表征。化合物属单斜晶系, 空间群为P21/c。锡原子均为畸型四面体构型, 化合物1以氢键作用形成一维链状结构, 化合物2以氢键和C-H…π作用形成二维网状结构。化合物12在340 ℃以下具有良好的热稳定性, 对人癌细胞Colo205、HepG2、MCF-7、Hela、NCI-H460均具有较好的体外抑制活性, 且具有一定的抑菌活性。  相似文献   
46.
丁二酸、戊二酸和己二酸分别与μ-氧-双[三(2-甲基-2-苯基)丙基]锡反应,合成了3个二[三(2-甲基-2-苯基)丙基锡]二元酸酯(CH2)n[CO2Sn(CH2CMe2Ph)3]2(n=2(1),3(2),4(3))。对化合物1~3进行了元素分析、红外光谱及核磁共振(1H,13C)表征,并通过X-射线晶体衍射分析测定晶体结构。化合物中锡与配基原子构成畸型四面体构型。试验表明,化合物23均对人癌细胞Colo205、HepG2、MCF-7、Hela、NCI-H460的增殖具有较强的抑制作用。  相似文献   
47.
By hydrothermal reactions of a newly designed ligand, 2-(p-tert-butylphenyl)-1H-imidazole-4,5-dicarboxylic acid (H3BuPhIDC) with Cd(II) or Zn(II), three metal-organic frameworks, [Cd(μ3-HBuPhIDC)(H2O)]·2H2O (1), [Cd(μ3-HBuPhIDC)(4,4′-bipy)0.5] (4,4′-bipy = 4,4′-bipyridine) (2), and [Zn23-HBuPhIDC)2(CH3OH)2] (3), have been obtained and characterized by elemental analyses, IR spectroscopy, and single-crystal X-ray diffraction. In 1, small countless diamond grids form a mesh structure and then are bridged through μ3-HBuPhIDC2? linkers building a 3-D framework. Compared with 1, 4,4′-bipy participates in the construction of a 3-D structure of 2. Polymer 3 shows an interesting 3-D open architecture, which contains infinite 1-D octagonal channels built by left- and right-handed helical chains. Thermal and solid-state photoluminescence properties of the polymers have been investigated.  相似文献   
48.
In this study, two new Mn(II) complexes consisting of a phenanthroline derivative and organic acid ligands, [Mn(3-PIP)(1,3-bdc)] n (1) and [Mn(3-PIP)2(1,4-bdc)] n (2) (3-PIP?=?2-(3-pyridyl)-imidazo[4,5-f]?1,10-phenanthroline, 1,3-H2bdc?=?benzene-1,3-dicarboxylic acid, 1,4-H2bdc?=?benzene-1,4-dicarboxylic acid), have been synthesized via hydrothermal reaction and characterized by Fourier transform infrared (FT-IR) spectra, elemental analyses, and single-crystal X-ray diffraction. Complex 1 is a one-dimensional (1-D) twisted double chain bridged by 1,3-bdc. The 3-PIP ligands in a parallel fashion are alternately attached to both sides of the 1-D double chain. Complex 2 exhibits a 1-D zigzag chain, to which pairs of crossed 3-PIP ligands are alternately attached. The two complexes are further extended into three-dimensional (3-D) supramolecular structures by hydrogen-bonding and π–π stacking interactions. The N-donor ligands with an extended π-system play a crucial role in formation and stabilization of the final supramolecular frameworks. Thermal properties of 1 and 2 and fluorescence of 2 are investigated in the solid state.  相似文献   
49.
Five new transition metal coordination polymers based on H2tzda and co-ligand bpe, {[M(tzda)(bpe)]·H2O}n [M=Zn(1), Cd(2), Mn(3), Co(4)] and [Ni2(tzda)2(bpe)2(H2O)]n (5) [H2tzda=(1,3,4-thiadiazole-2,5-diyldithio)diacetic acid, bpe=1,2-bis(4-pyridyl)ethane], have been hydrothermally synthesized and structurally characterized. Compounds 1-4 feature a 2D-layered architecture generated from [M(tzda)]n moiety with double-chain structure cross-linking bpe spacers. However, the conformations bpe adopts in 3 and 4 are different from those in 1 and 2 due to the rotation of C-C single bond in bpe. Polymer 5 exhibits an interesting 3D porous framework with 2-fold interpenetration, in which intriguing 1D double helix chains are observed. The photoluminescence properties of 1 and 2 in the solid-state at room temperature are investigated. In addition, variable-temperature magnetic data show weak antiferromagnetic behavior in 3-5.  相似文献   
50.
Three metal‐organic frameworks {[Cd( L )(glu)]?3 H2O} ( 1 ), {[Cd2( L )2(adi)2]?5 H2O} ( 2 ) and {[Cd( L )(sub)]?3 H2O?DMA } ( 3 ) ( L =pyridine‐3,5‐bis(5‐azabenzimidazole), H2glu=glutaric acid, H2adi=adipic acid and H2sub=suberic acid) were obtained under solvothermal conditions. Complex 1 shows a 2D (4,4) network constructing of Cd2‐glu and Cd‐ L chains. Complex 2 presents a 2‐fold interpenetrating 3D framework with pcu topology. Complex 3 is a 3D framework with cds topology. Three complexes with versatile structures were obtained by changing aliphatic dicarboxylate ligands with different lengths based on a N‐rich ligand. Moreover, the fluorescence measurements indicate that complex 1 is a good multifunctional chemosensor for the detection of Cr2O72? and MnO4? anions by fluorescence quenching effect, and ethylenediamine by fluorescence enhancement effect, with detection limits of 1.196 ppm, 0.551 ppm and 64.572 ppm, respectively. Both complexes 2 and 3 can selectively sense Cr2O72? anion with detection limits of 1.126 ppm for 2 and 0.831 ppm for 3 by a fluorescence quenching effect.  相似文献   
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