Solvent-Templated Self-assembly Of Coordination Polymers With Halogenated Aromatic Carboxylates: Syntheses, Structures And Properites

Coordination polymers with halogenated aromatic carboxylates haveattracted a great deal of attention for their complicated networks andpotential physical chemical properties for the important applications inthe separation, catalysis, magnetism, and optics. In this thesis, a series ofnew coordination polymers involving halogenated aromatic acids asbridging ligands and various transition metal ions as nodes have beenobtained at room temperature. This research focuses on the solvent effecton the structures and properties of coordination polymers. The contentswill be described as follows:1Three new polymeric CdIIcomplexes,[Cd（fip）（MeOH）₃]_n（1）,{[Cd₂（fip）₂（H₂O）₅]·4H₂O}_n（2）, and {[Cd₃（fip）₄（H₂O）₂][Cd（DMF）₂（H₂O）₄]·2DMF}_n（3）, have been prepared from the reactions of CdIIacetate with a rigid fluorinated ligand5-fluoroisophthalic acid （H₂fip）under different solvent systems. Complex1shows a one-dimensionalzigzag coordination chain with a mononuclear [Cd（COO）（MeOH）₃]unit, and complex2displays a2-D neutral layered structurecontaining a dinuclear [Cd₂（COO）₄（H₂O）₅] entity, while complex3presents a2-D anionic coordination network with linear trinuclear[Cd₃（COO）₈（H₂O）₂] clusters as linking nodes. The results clearlysuggest that the judicious choice of solvent systems does play acritical role in the construction of coordination frameworks withdistinct connectivity and dimensionality. The spectroscopic, thermal,and luminescent properties of1–3have also been investigated.2Two new polymeric MnIIcomplexes,{[Mn（1,2-BDC-F₄）（H₂O）₃]（EtOH）}_n（4） and [Mn（1,2-BDC-F₄）（H₂O）₂（DMF）]_n（5）, have beenprepared from the reactions of MnIIacetate with a perfluorinatedligand3,4,5,6-tetrafluoro-1,2-benzenedicarboxylic acid （1,2-H₂BDC-F₄） under different solvent systems. Both complexes crystallize in thetriclinic space group P1and have similar one-dimensional doublechain structures, which consist of unique8-membered and 14-membered rings. The effects of solvents as ligands and/or guestson the self-assembly of both supramolecular networks and on theirphotoluminescent properties in the solid state are discussed in detail.3Four new MnIIcomplexes {[Mn6（1,2-BDC-Cl₄）₆（DMF）₆（EtOH）₄]（DMF）₂（EtOH）₂}（6）,{[Mn₂（1,2-BDC-Cl₄）₂（H₂O）9]（H₂O）₂}（7）,[Mn（1,2-BDC-Cl₄）（H₂O）₂（DMF）]_n（8） and {[Mn₂（1,2-BDC-Cl₄）₂（H₂O）₆（DEF）]（H₂O）₂}（9） were prepared from the reactions of MnIInitratewith a perchlorinated ligand3,4,5,6-tetrafluoro-1,2-benzened-icarboxylic acid （1,2-H₂BDC-Cl₄） in different solvents. Single-crystalX-ray diffraction reveals that the structural transformation ofcomplexes6–9vary from a hexanuclear complex for6, a dinuclearstructure for7, one-dimensional double helix structure for8to a chiraldinuclear structure for9, respectively. In these reaction processes,solvents induced the formation of chiral network structures. Inaddition, the luminescent properties of complexes6–9in the solidstate were investigated.4Four new CuIIand NiIIcoordination polymers {[Cu（BDC-I4）（MeOH）₄]（H₂BDC-I4）（MeOH）₂}_n（10）,[Cu（BDC-I4）（dioxane）（MeOH）₂]_n（11）,{[Ni（BDC-I4）（MeOH）₄]（H₂BDC-I4）（MeOH）₂}_n（12） and {[Ni（BDC-I4）（DMF）₂（H₂O）₂]（DMF）₂（H₂O）}_n（13） with a rigid periodinated ligand2,3,5,6-tetraiodo-1,4-benzenedicarboxylic acid （H₂BDC-I4） have beenprepared in different solvent systems. X-ray diffraction structuralanalysis reveals that complexes10–13all possess one-dimensional（1-D） chain structures. However, the solvents play an important role inthe final supramolecular networks via both directed coordination andintermolecular O–H I, O–H O, or C–I π weak interactions. Inaddition, the luminescent properties of the free ligand H₂BDC-I4andcomplexes10–13in the solid state were investigated.