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Three new polyoxometalate (POM)-based metal–organic complexes, {Ni3(Hpytty)2[AlMo6(OH)5O19](H2O)4(CH3O)}·5H2O (1), {Ni3(Hpytty)2 [CrMo6(OH)5O19](H2O)10}·6H2O (2), and {Co2(pytty)[γ-Mo8O26]0.5 (H2O)5}·4H2O (3) (H2pytty = 3-(pyrazine-2-yl)-5-(1H-1,2,4-triazol-3-yl)-1,2,4-triazolyl), have been prepared by the solvothermal method. Complexes 1 and 2 show similar 0-D structures containing a [Ni3(Hpytty)2]4+ and Anderson-type [AlMo6(OH)5O19]4− /[CrMo6(OH)5O19]4− anions. The [γ-Mo8O26]4− anion was generated in-situ from the [IMo6O24]5− anion in 3, which shows a 3-D coordination structure constructed from 2-D Co-pytty metal–organic layers and γ-Mo8 anions. The results reveal that the POMs play key roles in tuning the diverse architectures of the final complexes. For 1–3, their adsorption properties for MB/GV and their electrochemical activities have been investigated. [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]

By introducing three pyridyl-1H-tetrazole derivatives to Keggin–Ag-(1,10-phenanthroline) system, five new polyoxometalate-based inorganic–organic hybrid compounds with different dimensionalities and structures, [Ag3(4-ptz)2Na(phen)(HPMo12O40)]·2H2O (1), [Ag4(3-ptz)2(phen)2(HPMo12O40)] (2), [Ag4(3-ptz)2(phen)2(HVW12O40)] (3), [Ag3(3-bptzb)(phen)2(PMo12O40)] (4) and [Ag3(3-bptzb)(phen)2(VW12O40)] (5) (phen = 1,10-phenanthroline, x-ptzH = 5-(x-pyridyl)-1H-tetrazole (x = 3, 4), 3-bptzb = 1,4-bis(5-(3-pyridyl)-tetrazolyl)butane), have been synthesized under hydrothermal conditions. Compound1is a 1-D belt architecture constructed from an Ag-4-ptz metal–organic chain and two Ag–PMo12O40–Na–phen inorganic–organic chains. When 3-ptzH was introduced as secondary ligand in2and3instead of 4-ptzH, two isostructural architectures were obtained, which contain a 1-D zigzag Ag-3-ptz chain with phen ligands hanging on both sides of the chain. The Keggin anions connect adjacent Ag-3-ptz chains to construct 2-D networks. When the flexible 3-bptzb was selected, isostructural4and5with 2-D networks were obtained, which were constructed from binuclear subunits and Keggin–Ag inorganic chains. The influence of three pyridyl-1H-tetrazole derivatives as secondary ligands on the dimensionalities and architectures of1–5was discussed. The electrochemical and photocatalytic properties of the compounds were investigated. [ABSTRACT FROM PUBLISHER]

Two new isopolymolybdate-based metal–organic complexes, [Cu2(2-ptz)2(Mo4O14)0.5] (1) and [Cu3(OH)2(3-ptz)4(γ-H4Mo8O26)(H2O)4]·10H2O (2) (2-ptzH = 5-(2-pyridyl)-1H-tetrazole, 3-ptzH = 5-(3-pyridyl)-1H-tetrazole), constructed from isomeric ligands with different N-donor sites were synthesized under hydrothermal conditions. In1, each [Mo4O14]4−cluster connected with six neighboring [Mo4O14]4−clusters through six binuclear [Cu2(2-ptz)2]2+subunits to yield a 2-D layer. In2, bidentate inorganic [Mo8O26]4−anions link the trinuclear [Cu3(OH)2(3-ptz)4] clusters to construct a 1-D chain. Adjacent chains connect through Mo–N bonds between the [Mo8O26]4−anions and pyridyl groups from the trinuclear clusters to form a 2-D layer. The effect of the N-donor sites of the rigid isomeric ligands on the structures of1and2was discussed. The electrochemical properties and photocatalytic activities of1and2have also been studied. [ABSTRACT FROM PUBLISHER]

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]

Three copper(II) isomers, [Cu(dtcd)(DNBA)2]n(1–3) (HDNBA = 3,5-dinitrobenzoic acid, dtcd = N,N-di(4H-1,2,4-triazole)cyclohexane-1,4-dicarboxamide), were synthesized in a one-pot reaction, and structurally characterized. Polymer1shows a 1-D single chain in which dtcd connect adjacent Cu2+ions, while DNBA?is monodentate. In2, every two Cu2+ions are linked by carboxylate of a DNBA?in a chelate-bridging mode into a binuclear unit, which is further connected by dtcd ligands into a 1-D double chain. In3, dtcd connect Cu2+ions via triazole nitrogens to generate 1-D single chains, which are further extended into a 2-D network by the amide oxygens of a dtcb from an adjacent chain. The pH plays an important role in product distribution of1–3. The coordination behaviors of dtcd and DNBA?also influence the final structures. Luminescent properties of1–3have been investigated. [ABSTRACT FROM PUBLISHER]

A Keggin-type polyoxometalate (POM)-based complex, [Ag5(L)3(H2O)2]·6H2O (1) (L = N,N′-bis(3-pyridinecarboxamide)-1,2-ethane), has been hydrothermally synthesized. Compound1shows a 3D + 3D interpenetrating network with a (3,4,4,4)-connected (4 × 62)2(42 × 62 × 82)(65 × 8)2topology, and it represents the first example of interpenetrating POM-based complex based on flexible bis-pyridyl-bis-amide ligands. Moreover, the electrochemical behavior and luminescence of1have been investigated. [ABSTRACT FROM AUTHOR]

Two new Pb(II) coordination polymers, [Pb(3-pdip)(L1)] · 0.5H2O (1) and [Pb(4-pdip)(L2)] (2) [L1 = heptane diacid, L2 = hexane diacid, 3-pdip = 2 -(3-pyridyl)imidazo[4,5-f]1,10-phenanthroline, 4-pdip = 2 -(4-pyridyl)imidazo[4,5-f]1,10-phenanthroline], have been obtained from hydrothermal reactions of Pb(II) nitrate with two flexible fatty carboxylic acids and two phenanthroline derivatives. Single-crystal X-ray diffraction analysis reveals that 1 is a 1-D staircase-like double chain coordination polymer extended by binuclear [Pb2N4O8] subunits and pairs of L1 ligands. Compound 2 exhibits a 2-D (4,4) network based on bi-metallic [Pb2N6O8] units and (L2)2/(4-pdip)2 double linkers. Furthermore, adjacent chains of 1 and layers of 2 are extended into 3-D supramolecular networks by π–π stacking interactions between aromatic rings of phenanthroline groups. The organic carboxylic acids with different lengths show great influence on the shapes of Pb(II)-carboxylate double chains. Phenanthroline derivatives possessing different sites of N-donors (3-pyridyl and 4-pyridyl) determine the final coordination frameworks of 1 and 2. Photoluminescence and thermal stabilities of 1 and 2 were also investigated. [ABSTRACT FROM AUTHOR]

A new 3-D cobalt(II) mixed ligand, metal-organic framework {[Co2(bpp)2(DNBA)4H2O] · MDNBA} (1), (bpp = 1,3-di(4-pyridyl)propane, DNBA = 3,5-dinitrobenzoate and MDNBA = methyl-3,5-dinitrobenzoate) was synthesized in aqueous-methanol medium. X-ray structural analysis of 1 revealed that the dinuclear cobalt clusters interlinked by two μ-carboxylates and a μ2 water molecule, acting as a node, are connected to four other clusters through bridging bpp to generate an extended neutral 3-D network. MDNBA was in-situ synthesized and encapsulated in the framework as a guest molecule. Moreover, the fluorescence spectrum shows 1 exhibits blue fluorescent emission in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

A new 1-D cadmium(II) mixed ligand dimer supramolecular ladder [Cd2L4(3,5-DNBA)2]H2O (1), (L = 3-(2-pyridyl)pyrazole and 3,5-DNBA = 3,5-dinitrobenzoate) was synthesized by hydrothermal methods. X-ray structural analysis of complex 1 revealed that two cadmium(II) cores are bridged by two deprotonated pyrazole groups of L, leading to dinuclear cadmium(II) [Cd2L4(3,5-DNBA)2]. The dimers are joined by hydrogen-bonding interactions between two different cadmium(II) dimers to form a one-dimensional ladder-like framework and stabilized by weak π-π interactions. Moreover, the fluorescence spectrum of compound 1 exhibits blue fluorescent emission in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

Two solid-state materials, {M 2 (DMF) 12 [Mo 6 O 19 ] 2 } (M = Co, Ni, DMF = dimethylformamide), have been designed, synthesized under mild reaction conditions and characterized by elemental analyses, IR spectra and single-crystal X-ray diffraction. The structures exhibit extended 2D networks through hydrogen bonds among polyanions and [M(DMF) 6 ] 2+ ; hydrogen-bonding interactions are responsible for the stability of the crystal. [ABSTRACT FROM AUTHOR]

Four coordination polymers, [Cu(4-dpyh)0.5(1,2-BDC)(H2O)3]·H2O (1), [Cu(4-dpyh)(1,3-BDC)(H2O)] (2), [Cd(3-dpyh)0.5(1,3-BDC)(H2O)2]·H2O (3), and [Zn(3-dpyh)(1,3-BDC)]·3H2O (4) [4-dpyh = N,N′-bis(4-pyridinecarboxamide)-1,6-hexane, 3-dpyh = N,N′-bis(3-pyridinecarboxamide)-1,6-hexane, 1,2-H2BDC = 1,2-benzenedicarboxylic acid and 1,3-H2BDC = 1,3-benzenedicarboxylic acid], have been hydrothermally synthesized. X-ray diffraction analyses reveal that1is a discrete [Cu2(4-dpyh)(1,2-BDC)2] dinuclear structure. Compound2exhibits a 2-D grid layer constructed from 1-D linear [Cu(1,3-BDC)]nchains and [Cu(4-dpyh)]nchains. Compound3features a 1-D ladder-like chain formed by the 1-D linear [Cd(1,3-BDC)]nchains and 3-dpyh bridging ligands. Compound4displays a 2-D undulated layer containing meso-helical [Zn(3-dpyh)]nchains and linear [Zn(1,3-BDC)]nchains. The neighboring dinuclear complexes for1, adjacent chains for3, and adjacent layers for2and4are further linked by hydrogen bonding interactions to form 2-D (for1) or 3-D supramolecular networks (for2–4). The influences of the different dicarboxylates and metal on the structures of1–4have been discussed. The electrochemical behaviors of1and2, the thermal stabilities and fluorescent properties of1–4, and the fluorescent selectivities of3and4have been investigated. Four new metal–organic coordination polymers have been hydrothermally synthesized by the flexible bis-pyridyl-bis-amide ligands and two different aromatic dicarboxylates. The influences of the different dicarboxylates and central metal ions on the structures of1–4have been reported. Moreover, the electrochemical behaviors of1and2, thermal stabilities, and the fluorescent properties of1–4have been investigated. [ABSTRACT FROM AUTHOR]

Two new cobalt complexes based on benzene tricarboxylates 1,2,4-H3BTC (1,2,4-H3BTC = 1,2,4-benzenetricarboxylate) or 1,3,5-H3BTC (1,3,5-H3BTC = 1,3,5-benzenetricarboxylate), and the bent dipyridyl ligand 2,5-bis(3-pyridyl)-1,3,4-oxadiazole (3-bpo) or its 4-pyridyl N-donor analog (4-bpo), formulated as [Co(1,3,5-BTC)(4-bpo)(H2O)3]2[Co(H2O)6] · 10H2O (1) and [Co3(1,2,4-BTC)2(3-bpo)2(H2O)12] (2), have been hydrothermally synthesized and characterized by elemental analyses, IR spectroscopy, TG analyses, and single-crystal X-ray diffraction. Structure analysis reveals that 1 is a 3-D porous supramolecular network based on the 1-D polymer chain , in which discrete [Co(H2O)6]2+ units and lattice water molecules are dispersed. In 2, bridging 3-bpo and 1,2,4-BTC connect cobaltions to form a trinuclear cobalt unit. Adjacent trinuclear cobalt units are further linked by π–π stacking interactions and hydrogen-bonding interactions to form a 3-D supramolecular framework. Electrochemical properties of cobalt(II) compounds bulk-modified carbon paste electrodes (1-CPE and 2-CPE) have been studied. [ABSTRACT FROM PUBLISHER]

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]

Depending on the in situ ligand transformation of 3,5-di(1,2,4-triazol-1-yl)benzonitrile (DTCN) to 3,5-di(1,2,4-triazol-1-yl)benzoic acid (DTCA) under hydrothermal condition, three polyoxometalate-based copper complexes, [CuI4CuII2(OH)2(H2O)4(DTCA)4(HPMoVI10MoV2O39)] (1), [Cu4(OH)2(H2O)4(DTCA)2(SiW12O40)]·11H2O (2), and {Cu2Cl(H2O)(HDTCA)2[CrMo6(OH)6O18)]}·4H2O (3), have been isolated through changing the polyoxoanions. Introducing Keggin-type polyoxoanions [PMo12O40]3− or [SiW12O40]4− to reaction systems, both 1 and 2 display 3-D framework structures containing Cu/DTCA metal-organic belts, and a kind of poly-Keggin chain derived from [PMo12O40]3− polyoxoanions exist in 1. When the Anderson-type polyoxoanion [CrMo6(OH)6O18)]3− is utilized, a 2-D grid-like layer resulted in 3, in which the DTCA ligands are embedded, revealing that the polyoxoanions have key roles in regulating the structures of complexes. The investigations on electrochemical properties and photocatalytic activities for the degradation of organic dyes of 1–3 have been carried out. [ABSTRACT FROM AUTHOR]

Four Cu(II)/Co(II) coordination polymers, [Cu(L)(BDC)(H2O)]·3H2O (1), [Cu(L)(DNBA)2] (2), [Co(L)2(DNBA)2] (3), and [Co(L)(NIPH)(H2O)]·H2O (4) (H2BDC = 1,4-benzenedicarboxylic acid, HDNBA = 3,5-dinitrobenzoic acid, H2NIPH = 5-nitroisophthalic acid, L = N,N′-di(3-pyridyl)sebacicdiamide), have been synthesized under hydrothermal conditions. The structures of1–4have been determined by single-crystal X-ray diffraction analyses and1–4were further characterized by infrared spectroscopy and thermogravimetric analyses. Complex1is a 2-D polymeric layer with a 4-connectedsqltopology. Complex2displays a 1-D zigzag chain. Complex3possesses a 1-D double-chain structure. Complex4exhibits a ribbon chain based on the 1-D [Co–L]nmeso-helical chain. Adjacent layers for1and adjacent chains for2–4are further linked by hydrogen bonding orπ–πstacking interactions to form 3-D supramolecular networks. The differences of carboxylates and metal ions show significant effect on the ultimate architectures of the four complexes. Thermal stabilities, fluorescent properties and photocatalytic activities of1–4were also studied. [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]