| Coordination polymer is a kind of coordination compound with periodiccrystalline frameworks constructed by the self-assembly of metal-containingsecondary units and organic linkers. As a kind of coordination polymers,metal-organic framework (MOF) materials hold ultrahigh porosity, specific surfacearea, tunable pore size, modifiable inner-pore surface and high thermal and chemicalstability. Great attention on MOFs has been paid by chemists for the potentialapplication in adsorption, storage, separation, identification, catalysis, optical,electrical, magnetic, biomedical and other fields. In this thesis, we chose such ligandsas isophtalic acid,2,4,6-pyridinetricarboxylic acid,2-amino-pyrimidine-4,6-dicarboxylic acid and2,2’-bipyridine-4,4’-dicarboxylic acid to synthesize someporous metal-organic framework products with specific ligand geometricconformation. In the thesis, we obtained some functional MOF materials as expected.The results are divided into six parts as following:In chapter one, we fully reviewed the basic concept, history development, andsynthetic techniques, and we also introduced some particular properties andapplication of the MOFs. In addition, the interest and scheme on our research topic isgiven in this part.In chapter two, we have synthesized two2D layed coordination polymersLNU-17and LNU-18by using isophtalic acid as ligand and Co(NO3)2as metal salt inthe same solvent condition and different ion environment, The results showed thatLNU-17possesses a isotactic chain in the b direction, while LNU-18, whichcrystallizes in P21, holds a syndiotactic chain in the b direction, so that LNU-17andLNU-18are a pair of isomers in configuration. This steric effect results in differentphysical properties, such as thermal stability, optics and magnetism.In chapter three, some N-heteroeyclie carboxylic acid derivative, such as H3PTCand H2APDC were used as angular ligand to prepare some novel functioncoordination polymers which can absorbed the geust of CO2. The product of H3PTCreacting with bismuth nitrate under hydrothermal condition is1D coordination polymer, named as LNU-19. A small molecule complexe LNU-20was synthesizedby react H2APDC with copper dichloride under solvothermal condition.In chapter four,2,2’-bipyridine-4,4’-dicarboxylic acid as a ligand with flexibleconformation change may be coined into the cis-isomer, and form into trianglaurprism or square structure unit by the coordination of zinc and cobalt. These secondarystructure units coordinatedly linked by some rare earths produced a series of3d-4fheterometallic porous coordination polymers LNU-n (n=21-27). The structures of allthe compounds were characterized and the properties were selectively studied.In chapter five, we selected LNU-21as the starting material to investigate thesingle crystal to single crystal transformations. Since the oxalic acid in LNU-21iseasily oxidized, we have observed the single crystal to single crystal transformationsof LNU-21at different oxidizing reagent. Three different products, such as LNU-21-1,LNU-21-2, LNU-21-3were abtained in the dilute solution of potassiumpermanganate, dilute aqueous solution of bromine at50℃and80℃,respectively.As a result, LNU-21-1is a3D coordination polymer by removal of oxalate rare earth,LNU-21-2is a2D product being partly oxidized and LNU-21-3was oxidized into asmall molecule,[Co(H2BPDC)(BPDC)2]·6H2O.In the last chapter, we have summarized some representative results includingthe structure and special properties of eleven coordination polymers, and threeproducts of single crystal transformation. In addition, some key synthetic factorswhether these products form or not are outlined in this part. |
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