Synthesis And Luminescent Properties Of {CuCN} Coordination Polymers Modified By Heterocyclic Ligands

Coordination ploymers containing Cu CN with novel structure have potential application in gas adsorption, catalyst, fluorescent material and anti-tumor. However the raw materia are often KCN, a kind of toxic material, which limit the further research. The exploration of the use of lower toxic reaction material for the synthesis of polymer is the attention between the material and chemist scientists. Under hydrothermal condition, nine coordination ploymers based on Cu CN building blocks were prepared with K4 [Fe(CN)6] by adjusting the reaction concerntration, the control of reaction temperature and time and characterized by elemental analysis, ICP and TG.(bimb=1,4-bis(imidazole-l-yl)butane,dip=1,5-di(1H-imidazol-l–yl)pentance,bix=1,4-bis(imidazol-l-ylmethyl)benzene,btb=1,4-bis(1H-1,2,4–triazol-1-yl)butane,bth=1,6-bis(1,2,4-triazol-1-yl)hexane,bib=1,4-bis(1-imidazoly)benzene,bbi=4,4'-bis(imidazoly)biph enyi, bdae=benzimidazole-5,6-dicarboxylic acid anhydride, H3pimdc=2-propyl-1H-imidazole-4,5-dicarboxylic acid)All the title complexes are characterized by IR spectroscopy, X-ray diffraction(XRD) and single-crystal X-ray diffraction. Structural analysis showed that: In compound 1, the smallest four-metal memebered ring units form two parallel chains by the hexacoordination copper atom and intermolecular forces. The compound 2 is a 2D layer with hexagonal lattice, which forms a 3D open pore structure via cyanide, the dip ligand as template filling the hole. In compound 3, Cu+ connects CN- forming2 D grid structure, which links the bix ligand to form a 3D “spider” structure. In compound 4, two types of twenty nuclear ring units with unilateral shared formation form a 2D layer structure, which is further connected by btb ligand to compose 2D sandwich structure. In compound 5, butterfly-shaped four-membered metallocyclic ring units link with each other to form a layer structure. These adjacent layers form a 3D sturcutre in ABAB mode through CN-. In compound 6, each Cu+ links adjacent two CN- forming {Cu(CN)2} structure units, which forms [Cu(CN)]n chains. These isolated chains form a 2D sturcutre with the bib coordination. In compound 7, bbi ligands and Cu atoms form a 1D chain, adjacent chains form a "ladder" structure through the free bbi ligands interspersing. The compound 8 contains two types of hexagonal bore connetced by dimeric{Cu2(CN)2} to form 2D layers, bdae ligands locates above the layers, which have the modification effect on the structure. In compound 9, adjacent K+ cations connect carboxyl oxygen atom ?3-O8 to form a dinuclear K clusters, which act as the connectors to link the Hpimda2- and {Cu CN} to form a 2D layer. The layers are further connected to form a 3D network by H3 pimda and {Cu CN}.The thermal stability properties show that compounds 1-9 ecompose above 190, 170, 280, 223, 214, 260, 130, 180, 100 ?, respectively, which show that the compounds have good thermal stability. As meanwhile, the fluorescence properties were studied for compounds 1-9, showing that these compounds have good fluorescence properties. The emmission bands are assigned to a metal-to-ligand charge transfer(MLCT:Cu—CN), which is expected to have the potential for light emitting devices.