Bipyridinium Derivatives As Synthons For The Self-assembly Of Functional Metal-organic Frameworks

Metal-organic frameworks(MOFs)as newly emerged materials have experienced rapid development in the last few years.The modular synthesis procedure allows integrating functional groups in their frameworks with varied applications.So synthesis of functional materials with excellent performance has been a hotspot in the research of the chemistry.1,1'-disubstituted-4,4'-bipyridinium salts(viologens)and their derivatives possess excellent photoelectrochromic properties and electron-accepting ability,and have been extensively applied to the assembly of solid functional materials.Due to the easy modification of the backbone and highly charged characteristics with interesting electron-active properties,the use of bipyridinium derivatives as synthons for the fabrication of functional metal-bipyridinium frameworks(MBPFs)has attracted increased interest over the past few years.Various bipyridinium-bearing ligands have been designed for the construction of functional MBPFs,and some of them present intriguing properties for potential applications including photochromism and photoswitching,sensing,molecule adsorption and separation.Ligand HBCbpyCl was synthesized following our previously reported method.We utilize it with metal ions and different auxiliary ligand to construct functional coordination polymers.We have successfully obtained seven compounds,which are characterized by IR,UV,TGA,EPR,X-ray single crystal/powder diffraction studies,gas adsorptions and photochemistry.We have systematically studied how the different molecular configuration and coordination assembly conditions affect the performance of adsorption and photochromic of compounds,the innovative features of my present work are described as follows:(1)We introduced auxiliary ligands with different functional groups in the process of assembling,and explore the different substituent effect on the structure and properties of the compounds.We found that different substituent groups will affect the structure accumulation of the compound and space configuration,resulting in differences in their property.(2)We try different reaction conditions and methods to improve the structure and properties of the compounds obtained step by step.We aim to get the desired holes compounds,using it to make adsorption test to study the adsorption performance of small molecule compounds.