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Three new coordination polymers, [Cu(butca)0.5(bipy)(H2O)]n · 2nH2O (1), [Zn(H2butca) (phen)(H2O)]n · nH2O (2), and [Cd(H2chhca)0.5(phen)(H2O)]n · 2nH2O (3) (H4butca =1,2,3,4-butanetetracarboxylic acid, H6chhca = 1,2,3,4,5,6-cyclohexanehexacarboxylic acid), were prepared and characterized by EA, IR, TG, and X-ray crystallography. Complex 1 is a 1-D double-chain coordination polymer in which tetradentate butca4- coordinates to four Cu(II) ions through four monodentate carboxylates. Complex 2 is a 1-D chain with tridentate H2butca2- coordinating to two Zn(II) ions through monodentate and chelating carboxylates. Complex 3 is a 1-D double-chain coordination polymer. H2chhca4- is octadentate coordinating to four Cd(II) ions through four chelating carboxylates. Hydrogen bonds and π-π stacking interactions play important roles in the formation of supramolecular architectures. The thermal stabilities of 1-3 show dehydrated coordination polymers are thermally stable in the range 260-400°C. [ABSTRACT FROM AUTHOR]

Abstract: Four novel coordination polymers constructed from flexible pamoic acid, namely [Co(pam)(4,4′-bipy)] n ·nH2O (1), [Ni(pam)(4,4′-bipy)(H2O)2] n ·2nCH3CN (2), [Cd(pam)(py)2] n ·npy (3) and [Mn2(pam)2(py)6(H2O)2] n ·2npy (4), (H2pam=pamoic acid, 4,4′-bipy=4,4′-bipyridine, py=pyridine), have been synthesized and characterized by elemental analysis, infrared spectra and X-ray crystallography. Complex 1 is a 2-D coordination polymer constructed from chelating bis-bidentate pam and 4,4′-bipyridine bridging ligands. Complex 2 is a 2-D coordination polymer assembled by bis-monodentate pam and 4,4′-bipyridine, where acetonitrile is filled in the rectangle channels. Both 2-D coordination polymers display undulated (4,4) grid layers as sql topology. Complex 3 displays a 1-D polymeric chain using chelating bis-bidentate pam as bridging ligand. Complex 4 exhibits an interesting bis-monodentate pam-Mn(II) 1-D polymeric chain, in which exist two-type six-coordinated manganese centers. Mn(1) is bound to four pyridine ligands, whereas Mn(2) is combined to two pyridine and two H2O molecules. Their thermal stabilities have been investigated. Cadmium complex 3 displays strong green luminescence with emission maximum at 543nm. [Copyright &y& Elsevier]

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]

Five new metal-organic frameworks based on 2,4,6-tris(4-pyridyl)-1,3,5-triazine (tpt) ligand have been hydrothermally synthesized. Reaction of tpt and AgNO3 in an acidic solution at 180 °C yields {[Ag(Htpt)(NO3)]NO3 · 4H2O}n (1). Ag(I) is trigonally coordinated by two pyridyl nitrogen and one nitrato oxygen to form a 1D zigzag chain. Reaction of tpt with CuSO4 affords {[Cu2(tpt)2(SO4)2(H2O)2] · 4H2O}n (2). Copper(II) is bonded to two pyridyl nitrogen, two sulfato oxygen, and two water oxygen atoms to form an elongated octahedral geometry. Each H2O ligand bridges two copper(II), whereas sulfate bridges copper(II) via μ-1,3 and μ-1,1 fashions. The copper(II)-sulfate-H2O 2D layers are linked by bidentate tpt to form a 3D polymeric structure. Reaction of Cu(SO4)2, tpt, and 1,2,4,5-benzenetetracarboxylic acid (H4btec) in the presence of piperidine gives [Cu(tpt)(H2btec)1/2]n (3). Copper(I) is located in a trigonal-pyramidal coordination environment and coordinated by three pyridyl nitrogen of tpt in a plane, whereas a carboxylate oxygen is coordinated to the copper(I) axially. The tpt-Cu forms a layer, and the layers are linked through H2btec2- to form a 2D double-layered coordination polymer. Replacing CuSO4 with ZnI2 in the synthesis gives {[Zn(tpt)(btec)1/2] · H2O}n (4). Zinc(II) is in a distorted tetrahedral geometry and linked through bidentate tpt and exotetradentate btec4- to form a 2D coordination grid. Reaction of tpt with CuCN leads to the assembly of a 3D metal-organic framework [Cu3(CN)3(tpt)]n (5). Copper(I) is trigonally coordinated by one pyridyl nitrogen and two cyanides to form an intriguing honeycomb architecture. Luminescence study shows that 1, 3, 4, and 5 have blue fluorescence, which can be assigned to be ligand-centered emissions. Thermal analysis shows that all of these complexes are quite stable, and especially for 4, the framework is stable up to 430 °C. [ABSTRACT FROM AUTHOR]

Abstract: Reactions of metal acetates with 4-amino-3,5-bis(3-pyridyl)-1,2,4-triazole (3-abpt) and co-ligands gave rise to four new complexes, namely [Zn2(3-abpt)(beta)(DMF) (H2O)2] n ·nH2O (1), [Zn(3-abpt)(ip)] n ·3nH2O (2), [Zn(3-abpt)(ip)(H2O)2] n ·2nH2O (3), and [Cu2(3-abpt)2(C6H5COO)4(H2O)2] n ·2nH2O (4) (ip=isophthalate, beta=1,2,4,5-benzenetetracarboxylate). Compound 1 is a 3D coordination polymer with uncommon 3,4-connected (62.8)2(62.82.102) network. Compounds 2–4 are all 1D coordination polymers, which exhibit diversity structures. Compound 2 is a tubular-like chain, 3 is a ring-like network, and 4 is a zigzag chain. Their thermal stabilities and the photoluminescence of 1 have also been 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]