Construction And Property Of Amide Decorated Metal Organic Frameworks Based On N-heterocyclic And Carboxylate Ligands

Metal-organic frameworks（MOFs） are an emerging class of porous materials, generally constructed from metal ions（or metal clusters） and organic ligands. Both of the structure and function of MOFs have been flexibly adjusted by the design of the metal centers and organic ligands. It is different from the zeolites. And more attentions have been paid to the MOFs. In this thesis, seven organic ligands with the –CONH- and their complexes with different metals were synthesized. Ten novel coordination polymers were obtained. Their structure and properties were studied. The main contents are as follows:（1） Three organic ligands with the functional group of tetrazole, H₃ ttzta,Hntban and Hntfca,were synthesized. Four coordination compounds, Zn（Hntban）₂（H₂O）₂（1）, Mn₃（Hntban）6（2）,Zn（Hntfca）₂（3） and Zn（H₃ttzta）（DMSO）（H₂O）（4） with different structures were prepared by hydro/solvothermal methods. The results of single-crystal X-ray diffractions show that the structure of the complex 1 is different from the complex 2 for the different metal centers, and the complexes 1, 2 and 3 are symmetric while the complex 4 appears asymmetric. The gas adsorption of the complex 4 was investigated, the results show the amount of adsorbed nitrogenup is up to about 32cm3/g. The above indicates that multi-topic ligands could be of benefit to construct porous MOFs.（2） One flexible ditopic carboxylate ligand H₂ dpba has been synthesized, and three rare earth complexes with H₂ dpba, [La（H₂dpba）（NO₃）（H₂O）]·3DMA（5）, [Nd（H₂dpba）（NO₃）（H₂O）]·3DMA（6） and [Sm（H₂dpba）（NO₃）（H₂O）]·3DMA（7）, are obtained by hydro/solvothermal methods. The results of single-crystal X-ray diffractions of the three complexes show that their structure is similar, the central metal ions are all nine-coordinated and there are one-dimensional channels inside three frameworks. The gas adsorption of compound 6 was carried out and the results show that compound 6 is able to adsorb both of N₂ and CO₂. One flexible tetratopic carboxylate ligand H₄ tbmbahas been synthesized and one zinc complex, [Zn（H₄tbmba）]（DMA）（C₂H₈N）₂（H₂O）₃（8）was obtained via hydro/solvothermal method. The results of single-crystal X-ray diffraction and powder X-ray diffraction reveal that compound 8 is an anionic MOFs with the dia topological net. The dye adsorption, ion exchange and gas adsorption were carried out. And it shows that the complex 8 could adsorb the rhodamine B rapidly, and its ability of adsorbing N₂ and CO₂ could be enhanced after Cu²⁺ exchange treatment. The above indicates multi topic carboxylate ligands could be of benefit to construct porous MOFs.（3） Three transition metal coordination compounds with mixed ligands,[Ni-2（L-1）₂（H₂bdtz）₂（H₂O）]·5DMA·H₂O（8）, [Co₂（L₂）₂（Hbdap）（DMA）（H₂O）₂]·2DMA（9）, and Zn（H₃tpim）（ H₂dpba）·DMA·3H₂O（10） were synthesized via hydro/solvothermal methods. The results of single-crystal X-ray diffractions show that the compound 9 exhibits a（2,8）-connected topological structure with dinuclear unit and its effective free volumeis up to 54.2%. In the structure of the compound 10, every single nuclear unit connects together forming one-dimensional chain and the combination of chains results in 2-D layers under hydrogen-bond interactions, further extend into 3-D supramolecular architecture under π-π stacking interactions.Similar to the compound 10, there are also one-dimensional channels and transformation from2-D layers to 3-D supramolecular architecture under hydrogen-bond and π-π stacking interactions in the structure of the compound 11. The gas adsorption shows that all the three compounds can adsorb certain amount of N₂, and the compound 10 can adsorb the gas CO₂. The above indicates mixed ligands and bridging ligands could be of benefit to construct porous MOFs.