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Two new polyoxometalate-based metal–organic complexes with rigid pyridyl-triazole-tetrazole ligand and two different polyoxometalates have been prepared and characterized. The electrochemical behaviors and the adsorption activities have been described. Two new polyoxometalate-based metal–organic complexes, namely, [Ni 3 (Htyptz) 2 (γ-Mo 8 O 26)(H 2 O) 8 ]·4H 2 O (1) and [Ni 3 (H 2 typtz) 2 (TeMo 6 O 24)(H 2 O) 8 ]·6H 2 O (2) [H 2 typtz = 3-(tetrazol-5-yl)-5-(pyrid-3-yl)-1,2,4-triazole] have been successfully synthesized under hydrothermal conditions. Their structures have been identified by single crystal X-ray diffraction, and further characterized by elemental analysis, infrared spectra (IR), and powder X-ray diffraction (PXRD). In complex 1 , the [Ni(Htyptz) 2 ] mononuclear unit link the adjacent 1D Ni-γ-Mo 8 O 26 inorganic chains conducing to the formation of the 2D layer, then the adjacent 2D layers are connected through hydrogen bonds to construct a 3D supramolecular network. Complex 2 is a 2D coordination network, which is constructed from 1D [Ni 3 (H 2 typtz) 2 ] chains and TeMo 6 anions. The different polyoxometalates play important roles in tuning the structures of the title complexes. In addition, the adsorption activities of complexes 1 and 2 for methylene blue (MB), neutral red (NR), rhodamine 6G (R6G), Orange II (OrII) have been investigated. Moreover, their electrochemical behaviors and electrocatalytic properties have also been studied. [ABSTRACT FROM AUTHOR]

Three coordination polymers (CPs), [Co(3-bptzp)(BDC)] (1), [Zn(3-bptzp)(BDC)] (2), and [Cd(3-bptzp)(BDC)] (3) (3-bptzp = 1,4-bis(5-(3-pyridyl)tetrazolyl)propane, H2BDC = 1,3-benzenedicarboxylic acid), were synthesized under hydrothermal conditions. The CPs were structurally characterized by single-crystal X-ray diffraction, infrared spectroscopy (IR), elemental analyses, and powder X-ray diffraction (PXRD). Complexes 1-3 represent the first examples of CPs based on the flexible bis(pyridyl-tetrazole) 3-bptzp. Structure analyses reveal that 1-3 are 1-D ring-containing polymeric chains. For 2 and 3, adjacent 1-D chains are extended to 2-D supramolecular networks by hydrogen bonding. Dye adsorption properties of 1-3, electrochemical properties of 1, and fluorescent-sensing behaviors of 2 and 3 have also been investigated. [ABSTRACT FROM AUTHOR]

Two Co(II) coordination polymers, [CoL(npa)]·2H2O (1) and [CoL(Hnpa)2] (2) (L = 1,4-bis(5,6-dimethylbenzimidazole-1-yl)benzene, H2npa = 5-nitroisophthalic acid), have been synthesized in different solvent systems and characterized by Infrared (IR) spectroscopy, elemental analysis, and powder and single crystal X-ray diffraction. Compound1was synthesized under solvothermal conditions with DMF as solvent and had a pair of L ligands adopting aμ2-bridging mode and connecting two Co2+cations to generate a 26-membered Co2L2loop. The npa2−link adjacent Co2L2loops via a bis(monodentate) bridging mode to create a 1-D channel-like chain structure. Compound2was obtained under hydrothermal conditions, and the carboxylate of the monodeprotonated Hnpa−adopt aμ1-η0 : η1coordination to connect adjacent Co2+cations into a 2-D polymeric layer. Theμ2-bridging L ligands connect adjacent 2-D [Co(Hnpa)]npolymeric layers into a 3-D NaCl-like framework. The Co2+cations and the L ligands in compounds1and2exhibit different coordination geometries and conformations. Effects of solvents on the construction of Co(II) coordination polymers were investigated. In addition, the electrochemical behavior of carbon paste electrodes containing1and2and the thermal stabilities of1and2were investigated. [ABSTRACT FROM PUBLISHER]

Two metal–organic coordination polymers, [Cu3(4-bpcb)2(1,2,4-btc)2(H2O)2] (1) and [Cu3(3-bpcb)3(btec)1.5] (2), have been synthesized from hydrothermal reaction of copper chloride with mixed ligands [4-bpcb = N,N′-bis(4-pyridinecarboxamide)-1,4-benzene, 3-bpcb = N,N′-bis(3-pyridinecarboxamide)-1,4-benzene, 1,2,4-H3btc = 1,2,4-benzenetricarboxylic acid, and H4btec = 1,2,4,5-benzenetetracarboxylic acid]. X-ray diffraction analysis reveals that1exhibits a 2-D layer structure and2possesses a three-dimensional (3-D) network. In1and2, CuIIions are connected by bridging 1,2,4-btc or btec to form 2-D polymeric layers. Cu-1,2,4-btc layer does not propagate into a 3-D coordination framework in1due to 4-bpcb showing monodentate coordination (via ligation of only one pyridyl nitrogen). In2, Cu-btec 2-D layers are further extended into a 3-D network with (64.82)3topology by 3-bpcb ligand inμ2-bridging coordination (via ligation of two pyridyl nitrogens). The different structures of the two complexes illustrate the influence of different polycarboxylates and N-donor positions of organic ligands on the formation of such coordination architectures. Moreover, the thermal properties and electrochemical properties of the copper complexes bulk-modified carbon paste electrodes have been studied. [ABSTRACT FROM AUTHOR]

A new 3-D copper(II) complex, formulated as [Cu2(btec)(en)2]n (1) [H4btec = benzene-1,2,4,5-tetracarboxylate, and en = ethylenediamine], was hydrothermally synthesized and structurally characterized by elemental analysis, IR spectroscopy, thermal gravimetric analysis, and single crystal X-ray diffraction. The structural analysis of 1 reveals that copper(II) connect by μ6-bridging btec to form a 3-D coordination polymer, in which four carboxylates of btec show monodentate and bidentate coordination. Complex 1 was used as solid bulkmodifier to fabricate renewable carbon paste electrode (1-CPE) by direct mixing method. The cyclic voltammogram of 1-CPE displayed one-electron quasi-reversible redox waves in potential range 300 to -300 mV due to Cu(II)/Cu(I). Moreover, 1-CPE showed electrocatalytic activity toward the reduction of nitrite. [ABSTRACT FROM AUTHOR]

Abstract: A novel inorganic-organic hybrid compound based on polyoxometalates (POMs) and organic ligand formulated as [Cu2(bpp)4(H2O)2](SiW12O40)∼6H2O (1) [bpp=1,3-bis(4-pyridyl)propane], was hydrothermally synthesized and structurally characterized by elemental analysis, single-crystal X-ray diffraction analysis, IR, TG, and cyclic voltammetry. Crystal data for 1: Orthorhombic, Pbcn, a=23.0085(19)Å, b=14.6379(12)Å, c=23.6226(19)Å, V=7956.0(11)Å3, Z=4, Dc=3.315gcm–3, and R(final)=0.0826. X-ray diffraction study reveals that compound 1 was the first interpenetrating network of 2-D metal–organic cationic coordination framework [Cu2(bpp)4(H2O)2] n 4n+, in which Keggin-type anions SiW12O40 4– has been used as a non-coordinating anionic template. The electrochemical property of 1-bulk modified carbon paste electrode (1-CPE) has been studied, and the results indicate that 1-CPE has good electrocatalytic activities toward the reduction of nitrite in 1M H2SO4 aqueous solution. [Copyright &y& Elsevier]

Five new Anderson-type polyoxometalate-based metal–organic complexes, [Cu 4 (μ 3 -OH) 2 (H 2 O) 6 (4-dpye) 2 (TeMo 6 O 24 )]·2H 2 O ( 1 ), [Cu(4-dpyb)(CrMo 6 (OH) 6 O 18 ) 2 (H 2 O) 2 ][Cu(4-dpyb)(H 2 O) 4 ](4-H 2 dpyb)·6H 2 O ( 2 ), H[Cu 2 (3-dpyb) 2 (C 2 O 4 )(CrMo 6 (OH) 6 O 18 )]·8H 2 O ( 3 ), [Cu 2 (4-dpyh)(CrMo 6 (OH) 5 O 19 )(H 2 O) 8 ]·10H 2 O ( 4 ) and [Cu 4 (μ 2 -OH)(μ 3 -OH)(H 2 O) 6 (4-dpyh)(TeMo 6 O 24 )]·H 2 O ( 5 ) (4-dpye = N,N′-bis(4-pyridinecarboxamide)-1,2-ethane, 4-dpyb = N,N′-bis(4-pyridinecarboxamide)-1,4-butane, 3-dpyb = N,N′-bis(3-pyridinecarboxamide)-1,4-butane, 4-dpyh = N,N′-bis(4-pyridinecarboxamide)-1,6-hexane), were hydrothermally prepared and structurally characterized by single crystal X-ray diffraction analyses and characterized by single-crystal X-ray diffraction, elemental analysis, IR, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA). Complex 1 is a 2D network, which is constructed from Cu 4 –TeMo 6 inorganic chains and 4-dpye ligands. Complex 2 contains two types of 1D chains. Complex 3 shows a 1D ring-like chain structure, in which the CrMo 6 anions act as fourfold monodentate ligands consolidating the [Cu 2 (3-dpyb) 2 (C 2 O 4 )] rings. Complex 4 is a 0D structure containing a dinuclear complex cation [Cu 2 (4-dpyh)] 4+ and discrete CrMo 6 anion. Complex 5 exhibits a 3D framework constructed from 2D Cu 4 –TeMo 6 inorganic layer and 4-dpyh ligands. The spacer lengths and N-donor sites of the bis-pyridyl-bis-amide ligands, as well as different polyoxometalates play important roles in tuning the structures of the title complexes. The electrochemical behavior and electrocatalytic properties, as well as the photocatalytic activities of the title complexes have been studied. [ABSTRACT FROM AUTHOR]

A novel monosubstituted Keggin-type polyoxometalate (POM)-based metal–organic framework [Cu4 IICu2 I(pzca)6(HPCuMo11O39)(H2O)6]·2H2O (1) (pzca=2-pyrazinecarboxylic acid) has been hydrothermally synthesized and characterized by IR, elemental analysis, TGA and single crystal X-ray diffraction analysis. Compound 1 shows a (2,3,4,7)-connected three-dimensional framework with {4·62 ·9·102}{4·92}{42 ·69 ·87 ·103}{6·9·10}2{9}2 topology, which is constructed from the monosubstituted Keggin chains [HPCuMo11O39]n 4n− and metal–carboxylate chains [Cu6(pzca)6]n 4n+. The electrochemical behavior and photocatalytic activity of compound 1 have been investigated. [ABSTRACT FROM AUTHOR]

Abstract: A new inorganic–organic hybrid compound [Cu2(L)4(H2O)2](SiW12O40)·8H2O (1) [L =1,1′-(1,4-butanediyl)bis-1H-benzimidazole] has been hydrothermally synthesized and characterized by IR, elemental analyses, XRD and TG analysis. Compound 1 exhibits a two-dimensional (2D) layer network constructed from metal–organic cations . There exist π–π stacking interactions among the benzimidazole rings of the adjacent 2D layers leading to a double-sheet structure. The Keggin-type [SiW12O40]4− anions acting as inorganic templates are sandwiched by the double-sheet structure. There exist hydrogen bonding interactions between [SiW12O40]4− anions and double-sheet layers, which extend the 2D network to a 3D supramolecular framework. The electrochemical behavior and electrocatalysis of compound 1 have been studied. [ABSTRACT FROM AUTHOR]

Abstract: Two new Keggin-type polyoxoanion-templated inorganic-organic hybrids, [Cu(3,4-bpo)2(H2O)(SiW12O40)] ⋅ (3,4-H2bpo) ⋅ 7H2O (1), and [Cu(4,4′-Hbpo)2(4,4′-bpo)(H2O)(SiW12O40)] ⋅ 3H2O (2) (3,4-bpo = 2-(3-pyridyl)-5-(4-pyridyl)- 1,3,4-oxadiazole, 4,4′-bpo = 2,5-bis(4-pyridyl)-1,3,4-oxadiazole), have been hydrothermally synthesized by changing the terminal N-donor’s orientation of the nonlinear ligands. X-ray structural analyses indicate that compound 1 shows a two-dimensional (2D) (4,4) grid sheet. The discrete SiW12O40 4− anions as templates locate on the square voids of the sheet. Compound 2 exhibits an arm-shaped chain structure. It is believed that the isomeric organic ligands play a key role in the structure control of the self-assembly processes. Furthermore, compound 1 bulk-modified carbon paste electrode (1-CPE) displays good electrocatalytic activity toward the reduction of nitrite. [Copyright &y& Elsevier]

Abstract: A new Preyssler-type polyoxometalates-based inorganic–organic hybrid compound [Co(Hbbbm)2(H2O)2(H2P5W30O110)]2·9H2bbbm·20H2O ( 1 ) [bbbm=1,1′-(1,4-butanediyl)bis-1H-benzimidazole] has been synthesized under hydrothermal conditions and characterized by IR, TG and XRD. Single crystal X-ray diffraction analysis reveals that compound 1 is composed of two Preyssler-type [H2P5W30O110]13− anions (P5W30), two [Co(Hbbbm)2(H2O)2]4+ cations, nine discrete protonated [H2bbbm]2+ molecules and twenty crystallization water molecules. Two P5W30 anions are covalently bridged by two [Co(Hbbbm)2(H2O)2]4+ cationic fragments to form a P5W30-based dimer. The dimers are ultimately extended to a three dimensional (3D) network by π∙∙∙π stacking and hydrogen-bonding interactions. Compound 1 represents the first bisupporting Preyssler-type structure modified by transition metal coordination complex (TMC). Additionally, the electrochemical behavior and electrocatalysis of compound 1 have been investigated. [ABSTRACT FROM AUTHOR]

Abstract: A new Wells–Dawson type polyoxometalate (POM)-templated compound, [Cu4(μ2-O)2(4,4′-bpo)4(INA)2(H2O)4][(P2W18O62)]·H2O (1) (4,4′-bpo=2,5-bis(4-pyridyl)-1,3,4-oxadiazole; INA=pyridine-4-carboxylic acid), has been hydrothermally synthesized. Compound 1 contains a novel bitrack sinusoid-like chain constructed from alternating dicopper units and non-linear rigid 4,4′-bpo linkers. Induced by POM templates, the adjacent chains formed elliptical spaces to accommodate the Wells–Dawson type anions. [Copyright &y& Elsevier]