| Investigation on the coordination complexes constructed by transition metals or lanthanide ions and ligands with muti-functional groups through coordinative bonds is an active research field in recent years. Due to the wide applications of coordination complexes in photoelectricity, magnetic material, redox catalysis, ion exchange, adsorption, separation, and molecular recognition etc., much attention has been devoted to the design and synthesis of novel kinds of structural topologies and compounds with special properties. It is important to master the factors influencing the structure of the coordination complex, such as solvent, conformations of ligands and temperature etc., so that we can control the formation of the complexes.In the past several decades, planar carboxylate ligands have been widely studied because of their strong coordination ability and varieties of coordination modes. As known, the ligand conformation and coordination geometries of the metal ion have signifinant influence on the final structures of a MOF, and a little change of the ligand may result in new topological complexes. In this thesis, we try to synthesize novel coordination complexes by the use of carboxylic acids or combination with imidazole/pyridine/phenanthroline ligands assembling with metal ions through coordinative bonds or supramolecular weak interactions and to study the factors influencing the final structures and properties. The coordination chemistry of carboxylate ligands has been reviewed. The assembly reactions of rigid benzene-muti-carboxylate and and N-donor ligands with metal ions have yielded 14 novel coordination complexes: Cu4(OH)2(SO4)(HBTC)2(bpy)·bpy (1), Cu1.5(H2O)(TMBTC)(bpy)·0.5H2O (2), Cd2(H2O)5(TMBTC)(bpy)2·NO3·3H2O (3), Ni(BITMB)(TMIPA)·2H2O (4), Zn(BITMB)(IPA)·H2O (5), Zn2(BITMB)2(HIPA)2(IPA)·H2O(6), Zn(TBDC1)0.5(TBDC2)0.5 (7), Er(BDC),.5(dmf)(H2O) (8), Tm(BDC)1.5(dmf)(H2O) (9), Er2(BDC)3(phen)2-3H2O (10), Tm(TBDC)1.5(dmf)(H2O)·2H2O (11), Er2(TBDC)3(phen)2·4dmf-2H2O (12), Tm(BDC)1.5(H2O)0.5dmf·C2H5OH·2H2O (13), Tm4(BDC)6(H2O)2(dmf)2·4dmf·2H2O (14).All complexes have been determined by single-crystal X-ray diffraction. Complex 1 is three-dimensional three-fold interpenetrated complex; complexes 2 possesses three-dimensional two-fold interpenetrated structure; complexes 3 belongs to three-dimensional architecture; complexes 4 is one-dimensional chain; complex 5 belongs to two-dimensional interpenetrated layers; complexes 6 is three-dimensional porous framework; complexes 7 possesses three-dimensional framework with a rare (3,5)-connected net based on a dinuclear SBU; complex 8 and 9 are both three-dimensional structures with two-fold interpenetrating nets; complexes 10-14 belong to three-dimensional non-interpenetrated lanthanide-organic framework. In complexes 1 and 2, the different geometries of the carboxylate ligands (planarity and nonplanarity) induced two different assembly units. The flexible BITMB adopts syn or anti conformations in the complexes 4,5,6 which can be controlled by the presence or lack of water in the reaction, moreover, the dimensionality of the product can be controlled by the ligand conformation of BITMB. Complex 7 can be transformed from a previously reported 2D double layer (MOF-47) by liberating the coordinated water and dmf molecules, which was confirmed by X-ray powder diffraction. Complexes 8 and 9 are isostructural; complexes 10-12 apply organic ligands containing large hindrance groups to prevent the formation of interpenetration; while complexes 13-14 use in-situ reactions generated rod-shaped SBUs to improve final framework, with non-interpenetrated porous nets. Complexes 3,5-7 have been characterized by fluorescent spectra and gas sorption studies have been done for complexes 12-14; complexes 1-8,12 and 13 have been measured by TGA.The results reported herein demonstrate that the use of non-plannar polybenzenecarboxylate ligands as precursors to bind transition metal or lanthanide metal ions, is a new approach for the formation of novel supramolecular networks with interesting physical properties. |
