Supramolecular Self-assembly And Functional Applications Of Tetraphenyl-pyrazole Ligands

Supramolecular chemistry is a chemical science originated from the cross of many sciences,which aims to study the interactions beyond molecular level,and is a rapidly developing subject.The life sciences,the materials sciences,the physical sciences,and the traditional chemical sciences are all exploring the extraordinary impact that supramolecules are having on their fields.The concept of self-assembly,extended from supramolecular systems,is even more subtle.This highly order and spontaneous process forconstructing supramolecular structures helps us understand the construction and maintenance of life.Then we can better understand life and transcend it.Therefore,based on the concept of supramolecular self-assembly,artificially designed metal-organic supramolecular structures have brought about new applications,including fluorescence imaging,information storage,industrial catalysis and other functions which can be designed through supramolecular construction.Based on the construction of supramolecular self-assembly system,the following work has been done in this thesis:In chapter 2,three new tetraphenyl-dipyrazole ligands were synthesized as isomers of each other.The supramolecular structure is stabilized by the coordination of pyrazole and binuclear metal vectors,and the reversible isomerization process becomes one-way irreversible isomerization process.These ligands reacted with binuclear metal vector[（bpy）₂Pd₂（NO₃）₂]（NO₃）₂ or[（bpy）₂Pt₂（NO₃）₂]（NO₃）₂（where bpy=2,2’-bipyridine）to give three different assembled supramolecular structures.The new assemblies were characterized by NMR,mass spectrometry and their structures were determined by X-ray single crystal diffraction.Experimental results show that Z and E ligands can be converted into each other under the condition of heating and irradiation,and this transformation is reversible and the final isomerization ratio can be about 50/50.The supramolecular structure constructed by the E configuration ligand and Pd can be completely transformed into the supramolecular structure constructed by Z and Pd metal under certain conditions,and the isomerization ratio is infinitely close to 100%.Supramolecules constructed by E and Pt metals can also achieve this transformation under certain conditions,but the transformation conditions are more demanding.In chapter 3,the luminescence properties and hydrogen-bonding self-assembly of pyrazole ligands are studied.Tetraphenylpyrazole ligands have the aggregation and crystallization induced emission properties.In addition,they also displayed the unique binding phenomenon with Hg（II）,which can be used as highly specific and selective fluorescent chemosensor for sensing of Hg（II）...