Synthesis And Properties Of Fiber-supported Small Molecules And Metal Complex Catalysts

Supported catalyst has been valued for its advantages of easy separation,recovery and reuse from the reaction system,easy separation and purification of products,and low environmental impact.In recent years,the study of cheap and easily available new carrier materials for supported catalysis in order to obtain higher activity and selectivity of the reaction has attracted the attention of chemists.Based on the concept of"green chemistry",starting from the development of a new,efficient,economical and environmentally friendly catalytic system,a series of catalysts for polymer fiber-supported small molecules and metal complexes have been designed and developed through the regulation of the structure of the carrier skeleton and catalyst.Catalytic application research has been carried out on the synthesis of some fine chemicals and the efficient conversion of biomass and CO₂.The ultra-high performance fiber polyphenylene sulfide?PPS?has excellent acid resistance,and its macromolecular chain contains a large amount of benzene ring framework,which can be used as a modification site for sulfonation reaction.In chapter2 of this article,a sulfonic acid functional fiber catalyst is synthesized by chlorosulfonation and hydrolysis,and used it for the catalytic conversion of biomass components into a platform compound methyl acetylpropanate?ML?reaction.Using fructose as substrate,the yield of ML was up to 70%after optimization of the system conditions,and the system could effectively simulate the catalytic reactor of rotating frame.It also has a good catalytic effect on other seven biomass components including hydroxymethylfurfural,furfuryl alcohol,glucose,sucrose,chrysanthemum powder,starch,and microcrystalline cellulose,and the yield of ML was 52-96%.The polyacrylonitrile fiber?PANF?contains a large amount of cyano and methoxycarbonyl groups in the polymer chain,which makes it easy to carry out the loading by ammoniating modification.In chapters 3 to 8 of this paper,we functionalized PANF with N-?3-aminopropyl?imidazole,and then salted with the halide to obtain five kinds of PANF-supported imidazolyl onium salt catalyst.And its properties were tested in the cycloaddition reaction of CO₂ with epoxide.The results showed that the PANF supported 3-carboxyethyl imidazole ammonium bromide had the best catalytic activity,six kinds of cyclic carbonate compounds were synthesized with81-99%yield by simulated rotating frame catalytic reactor.And the catalyst was recycled for 21 times with the yield of the product not decrease obviously.Subsequently,used N,N-dimethyl-1,3-malondiamine and triethylenetramine as ammonia reagents,fiber supported organic base catalysts with primary amine,secondary amine,and tertiary amine groups were prepared by twice ammonia reactions.In addition,the universality of Knoevenagel in water and other different solvents was confirmed,and a series of?,?-unsaturated compounds were synthesized in a nearly quantitative yield.Then,the phase transfer catalyst of PANF supported multistage quaternary ammonium salt was prepared by salinization,neutralization and quaternification of polyethylene polyamine functionalized fibers.Its outstanding phase transfer catalytic performance in the water-phase nucleophilic substitution reaction was verified in a rotating-frame reactor.On this basis,a series of fiber-supported metal complex catalysts were prepared by using the coordination properties of polyamine functional fiber with metal iron and copper salt.Among them,the simple synthesis of polyamine functional fibers and iron salt complexes,and the preparation of fiber-supported iron complexes catalyst is used as a supported Lewis acid have demonstrated excellent catalytic performance and application performance in the three-component Biginelli reaction.Some of the3,4-dihydropyrimidine 2-ketones were synthesized at yield of 81-94%;In addition,multi-stage tertiary amine functionalized fibers were prepared from polyamine functionalized fibers,and the fiber-supported copper complex catalysts were prepared by their complexation with copper salts,which could be used in the"click chemistry"CuAAC reaction in aqueous phase.It clarified the long-chain linker effect,as well as the multifunctional synergy of phase transfer activity on fiber carriers and copper catalysis.When the amount of catalyst is only 1mol%,the reaction can also be completed within 15 min,and the catalytic system can simulate the catalytic reactor with rotating frame effectively,it has the advantages of high yield and simple post-treatment process.Finally,the multistage quaternary ammonium salt-copper complex was constructed on the surface of fiber by using the multistage quaternary ammonium salt prepared in the previous period,and the loading mode of anion coordination was clarified.The loss of copper caused by the reaction of tertiary amine groups with halogenated hydrocarbons and acids is avoided and used to catalyze coupling and cycloaddition reactions involving terminal alkynes.It was found that in different solvents such as polar non-proton solvent ethyl acetate,non-polar solvent toluene,and polar proton solvent water,under mild conditionsin can efficiently catalyze the Glaser coupling reaction?yield 83-99%?,A³ coupling reaction?yield 81-94%?and“Click Chemistry”CuAAC reaction?yield 82-98%?,respectively,which showed good catalyst applicability and excellent recycling performance.Based on the study of the characterization and catalytic performance of fiber supported small molecular catalysts such as sulfonic acid,imidazolium salt,organic amine and quaternary ammonium salts as well as iron and copper complex catalysts loaded on fiber,the reliability of the preparation method and the stability of the catalyst application were fully verified.Compared with the reported research results,its mild reaction conditions,outstanding recycling performance,simple post-processing operations,effective system amplification and application in rotary frame reactor show that the fiber-supported catalysts with a good potential for industrial application,which provides a new way for continuous chemical industry production.