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Three Cu(I)-cyanide coordination polymers based on trigonal 1,3,5-tris(1H-imidazol-1-yl)benzene (tib) ligand, namely [Cu 3 (CN) 3 (tib)] n ( 1 ), [Cu 4 (CN) 4 (tib)] n ( 2 ), and [Cu 2 (CN) 2 (tib)] n ( 3 ), have been prepared and characterized by elemental analysis, IR, PXRD, thermogravimetry and single-crystal X-ray diffraction analysis. Complex 1 displays a 3D metal-organic framework with nanosized pores. Complex 2 is a 3D coordination polymer assembled by three μ 2 -cyanides and a μ 3 -cyanide with a very short Cu(I)···Cu(I) metal bond(2.5206 Å). Complex 3 is a 2D coordination polymer constructing from 1D Cu(I)-cyanide zigzag chain and bidentate tib spacer. Three Cu(I) complexes are thermally stable up to 250–350 °C. Complexes 1 – 3 show similar orange emission band at 602 nm originating from LMCT mechanism. [ABSTRACT FROM AUTHOR]

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: Hydrothermal reaction of CuCN with 2,5-bis(3-pyridyl)-1,3,4-oxadiazole (3-bpo) affords a wave-like infinite chain coordination polymer [Cu2(CN)2(3-bpo)] n (1). Replacement of 3-bpo by its isomer 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (4-bpo) could yields polymer [Cu(CN)(4-bpo)] n (2). In the complex 1, the bent 3-bpo ligand adopts bidentate chelating mode binds with the Cu(I)-cyanide chain to form 16-membered macrocyclic structure. The complex 2 exhibits a layered metal–organic framework, in which exo-bidentate 4-bpo ligand connects the Cu(I)-cyanide chains to form 2-D rectangle grid. Both of these Cu(I) complexes are thermal stable under 200°C and release 3-bpo or 4-bpo ligand in 200–360°C. Luminescent study reveals that 1 has green-light emission, while 2 has blue-light emission. [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: Hydrothermal reaction of CuCN, K3[Fe(CN)6] with 4-(6-amino-2-pyridyl)-1,2,4-triazole (apt) afforded a coordination polymer [Cu7(CN)7(apt)2] n (1), while solvothermal reaction of CuSCN with apt in acetonitrile afforded a coordination polymer [Cu2(SCN)2(apt)] n (2). Complex 1 shows two-dimensional polymeric network with large hexagonal channels constructing by CuCN chains and tridentate apt ligands. Complex 2 shows two-dimensional polymeric framework assembled by ladder-like [Cu(SCN)] n chains and bidentate apt ligands, in which thiocyanate acts as a tridentate bridging ligand. Both polymers are thermal stable and strong fluorescent in the solid state. [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]

A novel organic ligand, 6-diphenylamine carbonyl 2-pyridine carboxylic acid (HDPAP), and the corresponding lanthanide complexes, tris(6-diphenylamine carbonyl 2-pyridine carboxylato) samarium (III) (Sm-DPAP) and tris(6-diphenylamine carbonyl 2-pyridine carboxylato) dysprosium (III) (Dy-DPAP) have been designed and synthesized. The crystal structures and photoluminescence of Sm-DPAP and Dy-DPAP have been studied. The results showed that the lanthanide complexes have electroneutral structures, and the solid samarium complex emits characteristic red fluorescence of Sm (III) ions at room temperature while the dysprosium complex emits the DPAP ligand phosphorescence. The lowest triplet level of DPAP ligand was calculated from the phosphorescence spectrum of Gd-DPAP in N,N-dimethyl formamide dilute solution determined at 77 K, and the energy transfer mechanisms in the lanthanide complexes were discussed. [Copyright &y& Elsevier]

Four unique complexes with diverse coordination architectures were synthesized upon complexation of 5,5-(1,4-phenylenebis (methylene))bis (oxy)- diisophthalic acid (H 4 L) with zinc ions by using different solvent. namely, {[Zn(H 2 L) (bpp)]·DEF} n ( 1 ), {[Zn 2 (L) (bpp) 2 ]·4H 2 O} n ( 2 ), {[Zn 2 (L) (pdp) 2 ]·3H 2 O·DEF} n ( 3 ), {[Zn 2 (L) (pdp) 2 ].4H 2 O} n ( 4 ). Complexes 1 , 2 and 3 , 4 are obtained by varying solvents to control their structures. The size of solvent molecular plays an important role to control different structure of these compounds. Compound 1 is 2D waved framework with (4, 4) grid layer as sql topology. Compound 3 displays a (4,6)-connected 2-nodal net with a fsc topology. Compounds 2 and 4 are all three-dimensional network simplified as (4,4)-connected 2-nodal net with a bbf topology. The photochemical properties of compounds 1 – 4 were tested in the solid state at room temperature, owing to their strong luminescent emissions, complexes 1 – 4 are good candidates for photoactive materials. [ABSTRACT FROM AUTHOR]

Six Mn metal-organic frameworks have been synthesized under solvothermal conditions with V-shaped terphenyl tetracarboxylate ligands (H 4 ttac). Their structures were characterized by elemental analysis, infrared spectra, PXRD, thermogravimetric analysis, and single-crystal X-ray diffraction analysis. Crystal structures reveal that the coordination number of H 4 ttac ligand varies from 6 to 10, and each ligand links 4–8 Mn(II) ions. Coordination modes vary from η 6 μ 4 to η 10 μ 8 . The existence of DMF solvent can increase coordination number of the ligand. The first coordination saturated phthalate is presented. The variable-temperature magnetic studies indicate that complexes exhibit dominant antiferromagnetic behaviors. Structural parameters and coordination modes were summarized. The porosity of these complexes is less than 15%, indicating that the V-shape ligand is not a good choice to construct porous coordination polymers. [ABSTRACT FROM AUTHOR]

Abstract: Three new copper(II) azide coordination polymers with derivatives of 1,2,4-triazole as bridging coligands, namely [Cu2(admtrz)2(N3)4] n (1) (admtrz=4-amino-3,5-dimethyl-1,2,4-triazole), [Cu(4-abpt)(N3)2] n ·2nH2O (2) (4-abpt=4-amino-3,5-bis(4-pyridyl)-1,2,4-triazole) and [Cu3(2-ptrz)2(N3)6] n (3) (2-ptrz=4-(2-pyridyl)-1,2,4-triazole), were prepared and characterized by elemental analyses, IR spectra and X-ray structural analyses. Compound 1 has a 1D chain structure in which Cu(II) ions are bridged by end-on (EO) azides and admtrz ligands. This compound contains three kinds of coordination modes for Cu(II) ions, including tetrahedral, square pyramidal and octahedral geometries. Compound 2 displays an interesting 3D framework structure, in which the azide ligands link Cu(II) ions in end-to-end (EE) mode affording a 2D square layer. This 2D layers are further bridged by bent 4-abpt ligands to form an interesting 3D framework. Furthermore, this structure also exhibits an alpha-Po net topology. Compound 3 displays a 1D rectangle-like chain structure linked by azides adopting end-on (EO) and end-to-end (EE) modes and 2-ptrz ligands. The IR and thermal stabilities of these coordination polymers 1–3 have also been studied. [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]

Two new Cd(II) coordination polymers based on a flexible ligand 5-(bis(4- carboxybenzyl)amino)isophthalic acid (H 4 L) namely {[Cd 2 (L)(NMP) 2 (H 2 O) 2 ]·H 2 O} n (1) and{[Cd 4 (L) 2 (NMP) 2 (H 2 O)]∙2NMP} n (2) (NMP=N-methyl-2-pyrrolidone) have been prepared under hydrothermal conditions. Structural analyses revealed that 1 and 2 all exhibit three-dimensional network structures. Compound 1 shows 4-connect crb topology with [Cd 2 (CO 2) 4 ] as secondary building unit, while compound 2 can be regarded as a new 4,4,8-connect with a {411.615.82}{45.6}{46} topology with tetranuclear [Cd 4 (CO 2) 8 ]. By step-wise synthesis, tetranuclear cluster-based {[Cd 4 (L) 2 (NMP) 2 (H 2 O)]∙2NMP} n (2) can be synthesized successfully by using compound 1. The powder X-ray diffraction, the thermal stabilities, and solid-state luminescence properties of compounds 1 – 2 have also been investigated. Two 3D Cd coordination polymers with different topology were synthesized successfully. By step-wise synthesis, binuclear-cluster units can be transferred to tetranuclear cluster. Image 1 • Achieving the structure transformation from binuclear units to tetranuclear units by employing a step-wise synthesis method. • Two cadmium coordination polymers have been synthesized by using flexibly carboxylic ligand. • A new topology with 4,4,8-connected 3-nodal net. [ABSTRACT FROM AUTHOR]