Study On The Suzuki And Sonogashira Reactions Of Heteroaromatic Rings Catalyzed By Functional Palladium

Palladium catalyzed cross coupling reaction is an important reaction for the formation of carbon and carbon bonds,which is widely used in organic synthesis.The Suzuki reaction and the Sonogashira reaction are the most classic.The factors affecting the reaction are substrate activity,the selection of alkali,the choice of solvent and the selection of the catalyst.The ligands of Pd generally are phosphorus ligands,but they are unstable.After discharge,they are polluted to some extent,and the catalysts are afraid of oxygen.Therefore,most reactions need deoxygenation.As a kind of important supramolecular compounds,cyclodextrin is widely used in pharmaceutical research,catalysis research and artificial mimetic enzyme research because of its special external hydrophobic inner cavity structure.In recent years,the catalytic activity of cyclodextrin as a catalyst has become a hot spot of research.Through the study of the C-C cross coupling method,we try to find third kinds of catalysts to improve the reaction conditions and make them conform to the concept of green chemistry.Cyclodextrin derivatives a Cyclohexanediamine graft were designed and synthesized.The cyclodextrin derivatives can form metal complexes with palladium chloride.The new cyclodextrin metal complex can efficiently catalyze the Suzuki reaction and the Sonogashira reaction of mono(double)halogenated heteroaromatic rings in aqueous phase,and obtain the mono substituted coupling products,and it can be recycled and reused.In addition,the organic small molecules containing thiophene unit were prepared by one pot method of Suzuki and Sonogashira reaction,and the photoelectric properties were tested.We improved the palladium catalyzed cross coupling reaction of Suzuki and Sonogashira and successfully applied the method to the preparation of the precursor of small molecular functional materials.The main contents of this paper are divided into 3 parts:1.A new type of water soluble supramolecular metal palladium complexes has been synthesized: DACH-Pd-?-CD,using Suzuki coupling reaction and reduction reaction as the template.The catalyst was characterized by NMR,XRD,TEM,HR-TEM and XPS.2.In the study of catalytic performance of coupling reaction,we screened the best catalytic reaction conditions,and made Suzuki coupling reaction and Sonogashira coupling reaction for mono and disubstituted heteroaromatic rings and aromatic boric acid with different substituents.The substrates expanded by 25 and 16 respectively.And the catalyst can be repeatedly used,the catalyst dosage is bottom,and the substrate has a certain selectivity,the reaction conditions are mild,green and environmental protection.3.2,5-substituted five membered heterocyclic aromatic compounds are often used as light and liquid crystal materials,in this paper we proposed synthesis of small molecule compounds thiophene 2,5-substituted aryl,using functional Pd catalyst by using the Suzuki and Sonogashira reaction conditions step was prepared on both sides of asymmetric target compounds 35,27 of which are the new compound has not been reported before,we selected seven compounds for optical preliminary performance test.