Synthesis, Structure And Properties Of Polyhalogenated Phthalic Acid Coordination Polymers

On the basis of construction strategy of crystal engineering, a serious of coordination polymers with novel network have been constructed by empolying halogen substituted ammatic di-carboxylic acids as building block with different heterocyclic oganics as co-ligands, under appropriate conditions. Our current work involves developing a better understanding of the manner in which halogen substituted benzenedicarboxylates incorporate into hybrid structures, and find out the law of how substituent group, the synthesis conditions, the ancillary ligand and the weak interaction between molecular acting on coordination frameworks.Eight coordination polymers (1-8) varying from zero-dimentional dimer unit, one dimentional chain, two-dimentional (4,4)-net to2Dâ†'3D two fold interpenetrating and3Dâ†'3D four fold interpenetrating, have been builded’by empolying two kind of perfluorinated benzenedicarboxylates (Tfbdc and Tfph) as primary ligand. There are strong C-H…F hydrogen bonds present in those eight complex, especially in compound1and compound3in which the effect of hydrogen bonds are more obvious。For the existence of C-H…F hydrogen bonds, the two carboxylate groups of Tfbdc (complex1) are bended by10°relative to the phenyl ring plane and one armotic ring of4,4-bipy are twisted by40.7°relative to the other armotic ring. Those enrich our understanding of the form and strength of C-H…F hydrogen bonds and provide significant structure information for the follow-up complexes.Complex9-14have been synthesised by employing2,5-Dbta as building block and1,10-phen,2,2-bipy and5,5-Dm-2,2-bipy as co-ligand which is easy to form Ï€-Ï€ stacking interaction, under solvothermal conditions. The Ï€-Ï€ stacking phenomenon appear in those six coordination polymers. Interestiongly, there are dimer second building unit exist in the formed trasition-based CPs (complex9,11,12,13,14) and the expected C-H…π interaction have been constructed by introduce5,5-Dm-2,2-bipy in the synsesis process. More interestingly, even under the condition of Terminal ligand5,5-Dm-2,2-bipy participate in the coordination progress, alkali metal (Ca)-based coordination polymer form a3Dâ†'3D diamond topology.Six coordination polymers (15-20) varying from zero-dimention to two dimention, have been builded by empolying Tbta as primary ligand with different heterocyclic oganics as co-ligands. By the traction of weak interaction between molecular, those low dimentional structure stack into3D supramolecular framework. It is interesting that one armotic ring of4,4-Dm-2,2-bipy are bended by17.16°relative to the other armotic ring in compound15and the phenomenon of Ancillary ligand free appear in compond19.Twenty coordination polymers(complex21-40) have been synthesised by employing two kind of chlorine-substituted phthalic (Tcph and Dcph) as primary ligand. Those structure are different with those compound construct by phthalic, which show the effect of chlorine-substituted.