The Study Of Coordination Polymers Constructed From Flexible Multi-Carboxylic Acids

A series of coordination polymers ?CPs? with intriguing structures and potential applications constructed from four flexible carboxylic acids and transition metal ions have been synthesized under solvothermal/hydrothermal conditions and characterized by the single crystal X-ray diffraction, infrared spectra ?IR?, powder X-ray diffraction spectra ?PXRD?, elemental analyses and thermogravimetric analysis ?TGA?. The experimental conditions have been investigated systematically. We found many factors, such as coordination patterns of organic carboxylic acids, the introduction of auxiliary ligands and pH values of reaction systems may effect on the final structures. In addition, metal ions exchange, adsorption, photeluminescence and luminescent sensing small molecules properties of some compounds were also studied.1. An exceedingly rare porous metal-organic framework that is based on cadmium ions and multicarboxylate ligands, namely, Na_0.25[?CH₃?₂NH₂]_1.75[Cd?L?₂]· 2DMF·9H₂O ?1?, has been successfully synthesized under solvothermal conditions. Compound 1 exhibits a 2D net work that is constructed from left- and right-handed helical chains. Strikingly, compound 1 exhibits the highly efficient exchange of metal ions from the main framework components whilst maintaining the structural integrity and the crystallinity of the network. In addition, compound 1 also shows outstanding performance in the reversible adsorption of iodine.2. Nine new coordination polymers, namely, [Mn₅?HL?₂?H₂O?₂]·2C₂H₅OH· 4H₂O ?2?, Mn₃?L??phen?₂ ?3?, Mn₃?LX2,2'-bpy?₂ ?4?, Cd₃?LX2,2'-bpy?₂ ?5?, Cd₃?L??phen?₂ ?6?, Co2Na?HL??phen?₂0.5C₂H₅OH·H₂O ?7?, Co₃?L??4,4'-bpy? ?8?, Cu₂?H₂L??4,4'-bpy?4· 0.5H₂O ?9? and Cu₂?H₂L??ttp?₂·2C₂H₅OH·2H₂O ?9?, have been synthesized under hydrothermal conditions ?H₆L=1,2,3,4,5,6-hexakis?3-carboxyphenyloxymethylene? benzene, phen= 1,10-phenathroline,2,2'-bpy= 2,2'-bipyridine,4,4'-bpy= 4,4'-bip-yridine and ttp= 2-?6-?pyridin-2-yl?-4-p-tolylpyridin-2-yl?pyridine?. Compound 2 sho-ws a 2D layer structure. Compounds 3-6 display the similar 2D networks, whi-ch are further extended into a 3D supramolecular architecture by ?-? interactio-ns. Compound 7 exhibits a 3D binodal 4-connected framework with ?4²6³8?₂ topology. Compound 8 furnishes a 3D ?4,6?-connected framework with ?4⁴6²?(4⁴6¹⁰8)topology. Compound 9 reveals a 3D 4-connected framework with 66 topology. Compound 10 displays a 1D chain structure, which is further linked by hydrogen-bonding inter-actions to yield a 3D supramolecular architecture. The effects of coordination modes of the H₆L ligand and the N-donor ligands on the structures of products have been discussed in detail. Moreover, the diffuse reflectivity spectra of all the compounds and the solid state photoluminescent properties of compounds 5-6 were studied.3. Two Cu???-organic frameworks, Cu?H₂L?·DMF·2H₂O ?11? and Cu?H₂L?·3H₂O ?12?, constructed by a new macrocycle-based tetracarboxylate have been solvothermally synthesized by varying the organic solvents under the same synthetic conditions ?H₄L=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclot-etradecane-1,8-N,N'-dimethylene-isophthalic acid?. The structure of compound 11 is composed of hexagonal and triangular rings, showing the characteristic Kagome lattice. Compound 12 displays a ?44?-sql net with square channels. Strikingly, two compounds show different degrees of gas adsorption and reversible iodine adsorptions.4. Ten new coordination complexes, [Cd₃?H₂L??H₂O?₇]·6H₂O ?13?, [Mn₃?H₂L? ?H₂O?₇]·7H₂O ?14?, [Zn₃?H₂L??H₂O?₆]·6H₂O ?15?, [Co₃?H₂L??H₂0?₆]·5.75H₂O ?16?, [Fe3?H₂L??H₂O?8]·6.5H₂O ?17?, [Co₃?H₂L??teta?₃]·5H₂O ?18?, [Ni₄?L??teta?₄]·2.5H₂O ?19?, [Ni3?H₂L??teta??H₂O?₆]·6H₂O ?20?, [Cd₄?L??teta?₄?H₂O?₂]·H₂O ?21?, and [Cu₂?H₄L??teta?₂]·2H₂O ?22? ?H₈L= 1,4,8,11-tetrazacyclododecane-N,N'N",N'"- tetra-methylene-isophthalic acid and teta= 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraaza-cyclotetradecane? have been synthesized. Compounds 13 and 14 are isomorphous, and demonstrate the identical 3D ?4,6?-connected nets with ?6⁴·7²??6⁸·7⁶·8? topologies. Compounds 15-17 are isostructural and unfold 3D 4-fold interpenetr-ating frameworks with (4¹²·6³) topologies. Compound 18 is a 3D 2-fold interp-enetrating framework with (4¹²·6³) topology. Compound 19 features a 3D 6-connected (4¹²·6³) net. Compounds 20 and 21 reveal 2D layers, where hydrogen-bonding interactions further link adjacent layers together to obtain 3D supramol-ecular architectures. Compound 22 presents a 1D ribbon. These ribbons are co-mbined by ?-? stackings to produce a 2D supramolecular layer. The effects of the coordination pattern of H₈L, the teta ligand, and pH values on the resultant structures are discussed in detail. Besides, the fluorescent properties of H₈L and compounds 13,15 and 21 have been explored. In addition, the lumi-nescent sensing properties of compounds 13 and 15 for small molecules have been studied.