Research On The Construction And Properties Of Transition Metal Coordination Polymers Based On V-type Bisbenzimidazole Benzene

Due to the novel structures and many potential applications,coordination polymers have been a hotspot in the field of chemistry and materials science.Rational design and synthesis of coordination polymers and exploration of structure-property correlation are the important research contents.In this thesis,V-shaped 1,3-bis?benzimidazole?benzene?bbib?is chosen as the primary ligand,and seventeen novel transition metal coordination polymers have been synthesized under solvothermal conditions and structurally characterized by single crystal X-ray diffraction,elemental analyses,IR,powder X-ray diffraction?PXRD?and so on.In addition,the structures of these coordination polymers are investigated in detail and the laws of ancillary ligands and synthetic conditions in this system are summarized.Moreover,thermostability,fluorescent and magnetic properties about some complexes are also discussed.The main contents are summarized as follows:1.By using four dicarboxylic acids with different shapes and sizes as ancillary ligands and diverse transition metal ions,eleven complexes have been successfully constructed and structurally characterized.Structural analysis indicates that undersized carboxylic acids are in favor of the construction of variform complexes in bbib system,and 1D,2D and 3D frameworks are obtained.While the structures based on carboxylic acids with larger size are only 2D,indicating that organic ligands play an important role in the formation of diverse structures.Moreover,fluorescence studies show that complex 8 has high sensitivity and selectivity toward Fe³⁺and MnO₄^-,which is a potential bifunctional chemosensor.2.With the ancillary ligand of 1,4-naphthalenedioic acid?H₂ndc?and different transition metal ions,six complexes have been synthesized by the regulation of synthetic conditions and structurally characterized.The investigation suggests that solvent has a significant impact on the structure of targeted complexes.For example,13 and 14 exhibit 2D and 3D framework,respectively,when only using different solvents.Cd^?-and Cu^?-based complexes show 3D framework,while Zn^?-and Co^?-based complexes display 2D and 3D structure.Fluorescence measurements show that 12 and 14 can selectively sense Al³⁺and acetylacetone based on turn-on effect,respectively.Interestingly,14 is the first example of MOF-based turn-on fluorescent sensor for acetylacetone.The magnetic studies of 16 indacate antiferromagntic couplings between the adjacent Co^? ions within the dinuclear cluster.