Study On Synthesis Of Functionalized Alkynes And Metalloporphyrin Polymers By Sonogashira Coupling Reaction

Carbon-carbon（C-C）bonds is the essential structure in organic chemicals and it also is the basic unit to construct organic skeleton.Therefore,the construction of C-C bonds plays an important role in the fields of organic chemistry,pharmaceutical chemistry,polymer chemistry and materials science.Nowadays,transition-metal-catalyzed C-C bonds formation has been developed rapidly and widely used in the synthesis of natural products,drug molecules,fine chemicals and polymer catalysts.Alkynes are important structural units,which can undergo many transformations with valuable applications.It is of high research value to develop new efficient synthesis methods and application transformation of alkynes.Firstly,based on the study of Sonogashira coupling reaction,we investigated and summarized the previous works with traditional cross-coupling by free radical mechanism or other methods to construct Csp³-Csp bonds.The catalytic properties of metalloporphyrin polymers were summarized,and the synthesis of metalloporphyrin polymers was described.Based on the above,the research background and significance of the main work of this paper are put forward.Secondly,the construction of alkyl alkynes with traditional Sonogashira coupling reaction is very challenging.In this paper,non-noble metal cobalt catalyzed ammoniated alkynylation of alkenes to construct Csp³-Csp bonds,and alkyl alkynes with heterocyclic structure were prepared.The structure of the product was characterized by NMR and HRMS.In this reaction,an important cobalt intermediate is formed by pyridine coordination effect,which is then transmetallization with the alkyne-copper compound,and then reduced and eliminated to give the corresponding alkyne compound.Third,using halogenated metalloporphyrin and di-alkynyl biphenyl as monomers,using Sonogashira cross-coupling reaction.In Et₃N-THF solvent,a porous two-dimensional metalloporphyrin polymer Po P（MTPP）（M=Co、Mn）was successfully synthesized.The morphology,structure and elements of the catalyst Po P（MTPP）were characterized and analyzed by SEM,FT-IR,TG,BET and XPS.It was found that the catalyst Po P（MTPP）has been successfully synthesized and has the morphology of porous accumulation,high specific surface area,mesoporous pore size distribution and good thermal stability.Then Po P（MTPP）catalyst was used to catalyze the cycloaddition reaction of epoxide and CO₂.It was found that Po P（MTPP）could catalyze the cycloaddition reaction effectively under the condition of solvent free,and the yield of cyclocarbonate was up to 90%.In addition,nitrogen-doped metalloporphyrin polymer-based carbon material(C_PMTPP)was prepared from Po P（MTPP）.It was found that C_PMTPPshowed graphite-like lamellar morphology,among which,the crystal structure of C_{PCo TPP}was amorphous,while the crystal shape of C_{PMn TPP} was better,showing good catalytic performance for oxygen reduction reaction in alkaline medium.In a word,based on Sonogashira coupling reaction,bifunctionalized alkynes were synthesized and Csp³-Csp bonds was constructed.Metalloporphyrin polymer catalyst was successfully prepared by Sonogashira coupling reaction.The catalyst can not only be used for thermocatalytic synthesis of cyclocarbonate,but also can be used for oxygen reduction reaction after carbonization.The controllable porosity and unique structural characteristics of metalloporphyrin determine their excellent catalytic performance.It opens up a new way of nanostructured carbon materials for fuel cells,batteries and supercapacitors.