| As one class of emerging inorganic organic hybrid material with the special structure and properties, metal organic frameworks have potential applications in many fields. In this paper, we have designed, constructed and characterized two series of MOFs based on various functionalized imidazole and carboxylic acid ligand.1. Complexes 1-5({Co4(L1)4·11H2O}n(1), {Zn(L1)(0.5L2)(H2O)}n(2),{Co(L1)(L2)·2H2O}(3), {Cu(L1)(0.5L2)·H2O}n(4), {Ni(L1)(L2)·2H2O}n(5)) have been successfully synthesized based on 9, 10-dihydro anthryl-9, 10-bridge-α, β succinic acid and 1-(5-(1H-imidazol-1-yl)anthracen-1-yl)-1H-imidazole with rigid backbone and anthracyl under hydrothermal and solvothermal conditions, the structures were characterized and confirmed by P-XRD, elemental analysis, infrared spectroscopy and Diamond, TOPOS40. Complex 1 shows a beautiful butterfly structure, 2 is a three-dimensional wavy-like layer formed by hydrogen bonding, while 3 is a 2D layer,complex 4 with 3D frameworks can be simplified as a honeycomb networks by TOPOS40. 5 is a 3-connect and uninodal net forming a three-dimensional structure by stacking interactions. In order to study the thermal stability and the performance on photoluminescence and storage of the five complexes, we have carried out the TGA,solid-state UV, fluorescence in solid state and isothermal absorption for nitrogen and hydrogen experiments. The MOFs exhibit good thermal stability, and their decomposition temperature are about 250 ℃. The gas adsorption experiment shows that2 and 5 with the moderate adsorption capacity. 1-5 show outstanding fluorescent properties and fluorescence enhancement phenomena can be observed in 1 compared to the corresponding ligands, while the fluorescence quenching can also be observed in 1after adding nitrobenzene solution and the quenching percentages are increasing with the increase of the concentration of the nitro compds.2 We have constructed and characterized six MOFs({Co2(biim-4)2(A)2·H2O}n(6),{Co(biim-4)(B)2·4H2O)}n(7), {Ni2(biim-4)2(A)2·H2O}n(8),{Cd6(biim-4)1.5(L1)6·5H2O}n(9), {Co(BIE)(A)}n(10), {Ni(BIE)(A)}n(11))(biim-4 =1-(4-(1H-imidazol-1-yl)butyl)-1H-imidazole, BIE =1-(2-(2-(1H-imidazol-1-yl)ethoxy)ethyl)-1H-imidazole, H2 A = Benzopheno-4,4’dicarboxylic acid; H2 B = 1, 2-diethyl ether-4, 4 ’-dibenzoic acid) based on two flexible dis-imidazole ligands modified by alkyl chain or alkyl ether chain and three kinds of dicarboxylic acids with rigid or flexible skeleton. 6, 8 and 11 are 3D 2-fold interpenetration network. Complex 7 contains medium sized channel formed by the two-dimensional wave layers. Coordination polymer 9 shows the three-dimensionalstructure formed by the rare six nuclear cadmium clusters. The accumulation effect between molecules results in 3D structure of 10. TG testing shows that 9 and 10 are so favourable stable for heat that they do not collapse until reach 390 ℃ and 378 ℃,respectively. 7, 9 and 10 display mild adsorption capacity for N2 and H2. The six complexes exhibit strong fluorescence intensity in the solid, and complexes 6, 7 and 8show relatively enhancement compared to which of the corresponding ligands, in view of this, the Mg2+, Ca2+ and picric acid can be effectively sensing by fluorescence quenching after adding the above analyte to 6 and 8, and the quenching percentage rise with the increasing of the concentration of the analyte.3. Two different types of porphyrin derivatives decorated by diverse functional group have been successfully designed and synthesized based on the porphyrin ring fragment. Besides, we intend to prepare MOFs with potential applications based on these compounds, and the follow-up work is still in progress. |
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