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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]

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]

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]