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Solvothermal reactions of CuSCN with 4-amine-3,5-bis(3-pyridyl)-1,2,4-triazole (3-Abpt), 5-(4-pyridyl)tetrazole (4-Ptz), and 2-(n-pyridyl)benzimidazole (n-PyHBIm, n = 4, 3, 2) in acetonitrile afford six novel coordination polymers: [Cu5(SCN)5(3-Abpt)2]n (1), [Cu(SCN)(3-Abpt)]n (2), [Cu(SCN)(4-Ptz)]n (3), [Cu2(SCN)2(4-PyHBIm)]n (4), [Cu2(SCN)2(3-PyHBIm)]n (5), and [Cu2(SCN)2(2-PyBIm)(2-PyHBIm)]n (6). All these complexes were structurally characterized by X-ray diffraction analysis. 1 is the first example of a 1,1,1,3-μ4-tetradentate thiocyanate complex which displays a three-dimensional (3D) polymeric framework constructed from thiocyanate and tetradentate 3-Abpt. 2 exhibits a two-dimensional (2D) 4.82 network constructed from unidentate thiocyanate and tridentate 3-Abpt. 3 is a one-dimensional (1D) ladder-like double-chain polymer assembled by bidentate thiocyanate and 4-Ptz ligands. 4 shows a 2D 1,1,3-μ3-thiocyanate copper 4.82 network where bidentate 4-PyHBIm locates at both sides of the 2D layer. 5 dis...

Hydrothermal reactions of CuCN, K3[Fe(CN)6] with 2,2′-bipyridine, 1,10-phenanthroline or 2,6-bis(1,2,4-triazolyl)pyridine (btp) afford three coordination polymers, [Cu7(CN)7(bipy)2] n (1), [Cu2(CN)2(phen)] n (2) and [Cu3(CN)3(btp)] n (3). Complex 1 displays 1D polymeric ribbons which are assembled through Cu ··· Cu and π–π stacking interactions into a 3D framework. Complex 2 shows a 1D zigzag chain structure in which phen is a side ligand. In 3, the copper cyanide 2D polymeric networks are connected by tridentate btp to form a 3D metal-organic framework. These coordination polymers exhibit strong fluorescent emissions in the solid state.

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 AgNO 3 in an acidic solution at 180 degrees C yields {[Ag(Htpt)(NO3)]NO(3).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 micro-1,3 and micro-1,1 fashions. The copper(II)-sulfate-H2O2D 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 H 2btec2- 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 degrees C.

Hydrothermal reaction of CuCN, K 3 [Fe(CN) 6 ] with 4-(6-amino-2-pyridyl)-1,2,4-triazole (apt) afforded a coordination polymer [Cu 7 (CN) 7 (apt) 2 ] n ( 1 ), while solvothermal reaction of CuSCN with apt in acetonitrile afforded a coordination polymer [Cu 2 (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.

Two amino acid complexes, [Cd(L-glu)(H2O)] n · nH2O (1) and [Co(L-asp)(phen)(N3)] · 2H2O (2) (L-glu = L-glutamate, L-asp = L-aspartate, phen = 1,10-phenanthroline), have been synthesized and characterized by elemental analyses, IR spectra and TG-DSC analysis. Single crystal X-ray structure analyses revealed that each L-glutamate acts as a pentadentate ligand binding to three octahedral Cd(II) atoms through the amino group and two carboxyl groups to form a neutral helical network. Complex 2 is a mononuclear compound in which Co(III) is octahedrally coordinated by tridentate L-aspartate, monodentate azide and chelating phen ligand. Thermal stability and fluorescence of 1 have been investigated. The complex shows strong blue fluorescence in the solid state.

Hydrothermal reaction of ZnSO4 · 7H2O with 1,3,5-benzenetricarboxylic acid (H3btc) and 2,6-bis(1,2,4-triazolyl)pyridine (btp) afforded a novel metal–organic network {[Zn3(btc)2(btp)2(H2O)2] · 4H2O}n (1) with a supramolecular cocrystal [H3btc · btp · H2O]n (2). The complex 1 exhibits an unusual network containing two molecular squares and a rectangle. The networks interpenetrate to make a 3D metal–organic framework, which is quite thermal stable. Compound 2 shows a 2D supramolecular network assembled through strong hydrogen bonds.

Two new cyano-bridged bimetallic complexes, [Cu(TAAB)Fe(CN) 5 (NO)]·2H 2 O ( 1 ) and [Mn(bpy) 2 (H 2 O)Fe(CN) 5 (NO)]·H 2 O ( 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.

Hydrothermal reaction of CuCN, K3[Fe(CN)6] and 1,10-phenanthroline affords a novel cyanide-bridged copper(I) coordination polymer [Cu3(CN)3(phen)]n (1). The complex displays an interesting one-dimensional neutral double helical framework with (phen)Cu–CN– side-arms as interchain bridges. The double helical chains are close packed in a parallel fashion, and the phen ligands stack in an interpenetrating mode, which leads to π–π interactions between parallel phen planes. The thermal stability and fluorescent property have also been investigated.

In the title complex, [Mn(C(8)H(4)NO(6))(2)(H(2)O)(4)] x 2H(2)O, cyclic water tetramers forming one-dimensional metal-water chains have been observed. The water clusters are trapped by the co-operative association of coordination interactions and hydrogen bonds. The Mn(II) ion resides on a center of symmetry and is in an octahedral coordination environment comprising two O atoms from two 5-carboxy-2-nitrobenzoate ligands and four O atoms from water molecules.