Synthesis,Characterization And Heterogeneous Catalytic Performance Of Porphyrin-based Porous Organic Polymers

Recently,with the rapid development of the global science and technology,various problems are emerging one after another,such as pollution and excessive energy consumption.Scientists are encouraged to carry out scientific research based on the principles of sustainable development and green environmental protection.From the perspective of materials science and chemistry,the designed and synthesized materials not only have excellent properties,but also minimize pollutants when they were used.To date,the flourishing porous materials can well meet with these requirements mentioned above due to their large surface area,permanent porosity and adjustable structure.The third chapter of this thesis,a catalytically active conjugated microporous polymer（SP-CMP-Cu）is constructed by the polycondensation reaction of Salen-Cu（salen=N,N’-bis（3-tert-butyl-5-formyl salicyl）ethylene diamine）and pyrrole,then its structure was characterized.As an amorphous material,SP-CMP-Cu exhibits superior catalytic activity,selectivity and recyclability for the Henry reaction in the water phase owning to the medium specific surface area,uniform pores,the chelation of Cu catalytic sites and the hydrophilicity of the porphyrin structure.In addition,as a heterogeneous catalyst,the Salen-porphyrin-based conjugated microporous polymer is proved as a multifunctional catalytic platform that can be used for synergistic catalysis and/or asymmetric organic conversion,which further demonstrates the unique attraction of organic porous material based on the porphyrin structure.In the fourth chapter of this thesis,a covalent organic framework（Por-COF-Zn）based on the structure of porphyrin and thiophene is synthesized by one-pot method with 5,10,15,20-tetra-（4-aminophenyl）porphyrin（TAPP）,thieno[3,2-b]thiophene-2,5-dicarbaldehyde and acetic acid Zinc.The obtained material has high stability,large specific surface area and rich photophysical properties.Por-COF-Zn can effectively separate light-induced electron-hole pairs and response to photocurrent,thus it can be used to catalyze the synthesis of benzimidazole under the irradiation of white LEDs in aqueous phase at room temperature.Furthermore,after the catalytic cycle experiment,the crystallinity of the material decreased after ten cycles,but it still has good photocatalytic activity,which proves that the material is an excellent heterogeneous photocatalyst.Moreover,the EPR test shows that the active species produced by the catalyst under light is ¹O₂,and the catalytic site of the catalyst is not limited to metal zinc but also contains organic structural framework.Therefore,porphyrin-based organic porous materials have great potential as photocatalysts.