The Construction Of Indole And Quinolone Derivates Via Transition-metal-catalyzed C-H Functionalization Reactions

In the recent years,transition-metal-catalyzed C-H fuctionalization reactions has has attracted great attention from synthetic chemists.Direct C-H fuctionalization can not only avoid pre-functionalization of the raw materials,shorten the reaction steps,but also improve the atom economy,reduce environmental pollution.Manyheterocyclicderivativeshavebeensynthesizedthrough transition-metal-catalyzed C-H functionalization.However,these methods usually use some expensive transition metals,such as palladium,ruthenium,rhodium,etc.,and with the low regioselectivity.Therefore,it is very important to develop cheap and efficient metal catalysts to construct heterocyclic compounds.In this paper,we achieved the transition-metal-catalyzed C-H bond functionalization of heterocyclic compounds in the specific position.In addition,the transition-metal-catalyzed radical tandem reaction was used to construct the heterocyclic compounds.The content of this thesis are summarized as follows:1.We carried out the study of copper catalyzed C-H nitration of quinoline derivates.a series of nitro substituted quinoline derivatives at the C5 position was obtained between the reactions of 8-aminoquinoline amide derivatives and sodium nitrite.The reaction features wide substrate scope,high yields,mild reaction conditions and extremely short reaction time.At the same time,the structure of the product was further determined by single crystal diffraction and the possible mechanism was speculated.In addition,we also performed the gram scale synthesis under the standard conditions.Importantly,nitro-containing quinolone derivatives were obtained through this transformation.It is noteworthy that the reaction overcomes some shortcomings in the traditional nitration strategies,such as requiring harsh conditions?HNO₃/H₂SO₄strong acid system?,and poor regioselectivity.This newprotocol may provide a green and efficient approach to construct nitrated quinoline derivatives with potential biological activity.2.We carried out the study of nickel catalyzed synthesis of oxindole derivates.A series of fluorinated 3,3-disubstituted 2-oxindole derivates were obtained with excellent yields,by using easy available N-arylacrylamides as the sustrate,inexpensive R_fX as the fluoro source,as well as employing unprecious nickel salt as the catalyst.Based on the control experiments and previous reports,we described a radial-based mechanism.Two new C-C bonds were formed with one step and C-H functionalization of Aromatic ring was achieved in this reaction?In addition,This strategy may provide a new approach to construct fluorinated oxindole derivates with potential biological activity and functional material properties.