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Abstract: The reactions of metal salts with pyrazine-2,3-dicarboxylic acid (H2pzdc), pyridine-2,5-dicarboxylic acid (H2pydc), pyrazine-2,3,5,6-tetracarboxylic acid (H4pztc), 4,4′-bipyridine (bipy) and 1,10-phenanthroline (phen) afforded four new ternary complexes, namely [Co2(pzdc)2(bipy)(H2O)2] n ·3nH2O (1), [Zn2(pzdc)2(bipy)(H2O)2] n ·3nH2O (2), [Co(pydc)2(H2O)2](H2bipy) (3) and [Cu2(pztc)(phen)2(H2O)2]·2HNO3·2H2O (4). The metal centers are all six-coordinated. Compounds 1 and 2 are 2D coordination polymers exhibiting wave-like polymeric networks. The 2D layers are stacked in an interpenetrating mode to form double-layered frameworks, which possess ∼8Å×6Å tunnels occupied by (H2O)6 clusters. Compound 3 is a mononuclear supramolecular compound in which 4,4′-bipyridine is protonated and acted as a cationic building block. Compound 4 is a centro-symmetric binuclear complex. Pztc4− as a hexadentate ligand coordinates to two Cu(II) ions to form four chelating rings. Phen are arranged in an ABAB parallel fashion to form a supramolecular architecture incorporating HNO3 lattice molecule. The thermal stabilities of 1−4 and luminescence of zinc complex 2 were also investigated. [Copyright &y& Elsevier]

Abstract: Three supramolecular compounds, [Mn2(chda)(phen)4(H2O)]·(ClO4)2·phen·4H2O (1), [Cu(mal)(bipy)] n ·2nH2O (2) and [Cu(ca)2(bipy)]·2H2O (3) (chda=1,1-cyclohexanediacetate, mal=maleate, Hca=cyanuric acid, bipy=2,2′-bipyridine), have been synthesized and characterized by elemental analyses, IR spectra, thermal analyses and X-ray structural analyses. Compound 1 is a carboxylate-bridging binuclear complex incorporating uncoordinated 1,10-phenanthroline bonded by hydrogen bonding and π–π stacking interactions. Compound 2 is a 1D zigzag chain carboxylate coordination polymer incorporating cyclic (H2O)4 tetramers of lattice water, which further connect the zigzag chains through strong hydrogen bonds to form 2D supramolecular network. Compound 3 is a mononuclear complex in which H-bonding (H2O)8 water clusters further combine the complex through hydrogen bonds to form supramolecular framework. Thermal stabilities of 1 and 3 have also been investigated. [Copyright &y& Elsevier]

Abstract: Two new cyano-bridged bimetallic complexes, [Cu(TAAB)Fe(CN)5(NO)]·2H2O (1) and [Mn(bpy)2(H2O)Fe(CN)5(NO)]·H2O (2) (where TAAB=tetrabenzo[b,f,j,n][1,5,9,l3]tetraaza-cyclohexadecine and bpy=2,2′-bipyridine), have been synthesized and characterized by elemental analyses, IR spectra and TG-DSC analyses. Single crystal X-ray structure analyses revealed that the complex 1 has a cyano-bridged binuclear structure in which Cu(II) center is coordinated by tetraazacyclic TAAB ligand to form an intriguing saddle-shaped structure, and Fe(II) center is in an octahedral coordination environment with nitrosyl group trans to the cyano-bridge. In complex 2, Mn(II) center is cis six-coordinated and linked to nitroprusside though a bridging cyanide group to form a binuclear structure, while the nitrosyl group is cis to the cyano-bridge. The thermal stabilities of both complexes were investigated, which shows the nitrosyl and cyanide groups of nitroprusside released by two-steps in the temperature range of 200–380°C. [Copyright &y& Elsevier]

Abstract: Two acetylenedicarboxylate complexes, [Mn2(C4O4)(phen)4(H2O)2](ClO4)2·H2O (1) and [Cu(C4O4)(2,2′-bpy)] n (2), have been synthesized and characterized by elemental analyses and IR spectra. MnII ions have distorted octahedral coordination geometry and bridged by C4O4 2− to form a binuclear structure. Thermal analysis shows C4O4 2− released in the range of 180–280°C. CuII is five-coordinated by 2,2′-bipyridine and three oxygen atoms from three different C4O4 2− ligands, leading to a square-pyramidal coordination geometry. Each C4O4 2− links three CuII centers through bifunctional carboxylate to form a polymeric structure of (4,4) layers with nodes being dimer of Cu2O2 and bridges of C4O4 2−. Its variable-temperature magnetism was also investigated. [Copyright &y& Elsevier]

Abstract: Reactions of 4-amino-3,5-bis(3-pyridyl)-1,2,4-triazole (3-abpt) with metal acetates gave rise to four new complexes [Cu(3-abpt)(ip)] n ·2nH2O (1), [Co(3-abpt)(ip)(H2O)2] n ·2nH2O (2), [Ni(3-abpt)(tp)(H2O)2] n (3) and [Cu(3-abpt)2(CH3COO)2(H2O)2] (4) (ip=isophthalate, tp=terephthalate), which were characterized by EA, IR and X-ray crystallography. Compound 1 consists of two kinds of ring-like chain which are interconnected to form an unusual two-dimensional layered motif. Compounds 2 and 3 are both 1D ring-like infinite chains. Compound 4 is a mononuclear complex. The thermal stabilities of coordination polymers 1–3 have been investigated. [Copyright &y& Elsevier]