Study On Coupling Reaction Of Trifluoromethyl(Acyl) Hydrazones With Aryldiazonium Tetrafluoroborates

Trifluoromethyl（CF₃）group is an important functional group for introducing fluorine into organic compounds.Due to its unique electronic effect,its introduction into organic compounds can significantly improve the stability,metabolic stability and lipophilicity of the parent compounds.Trifluoromethyl compounds have been widely used in medicines,pesticides and materials.Many efficient methods have been developed for introducing trifluoromethyl functional group into organic molecules.Researchers have developed many efficient methods for introducing trifluoromethyl functional groups into organic molecules.There are two main methods to introducing trifluoromethyl group into organic molecules:direct trifluoromethylation and trifluoromethyl building block synthesis.The trifluoromethyl block method is widely used in the synthesis of trifluoromethyl compounds due to its low cost,easy availability in industry,stable properties and wide variety.Among them,trifluoromethyl（acyl）hydrazone compounds is one of the most used fluorine-containing synthetic blocks,which have been greatly developed in recent years.This thesis mainly investigates the coupling reaction of trifluoromethyl（acyl）hydrazone.This thesis consists of the following three chapters:Chapter one:Research progress in the Reactions of Trifluoromethyl（Acyl）HydrazonesIn this chapter,the development of fluorine chemistry and the application of trifluoromethyl compounds in medicine,pesticides,materials and other fields are briefly described.Then,the application of trifluoromethyl（acyl）hydrazone as a trifluoromethyl building block in organic synthesis is systematically reviewed.The research progress of N-alkylation,1,2-addition and cycloaddition of trifluoromethyl（acyl）hydrazones was reviewed.Chapter two:Study on the Coupling Reaction of Trifluoromethyl（Acyl）Hydrazones and Aryldiazonium TetrafluoroboratesThis chapter mainly explores the coupling reaction of trifluoromethyl（acyl）hydrazones with aryl diazo tetrafluoroborates.Firstly,the effects of bases,solvents,material ratio and temperature on the reaction yield were investigated,and the optimal reaction conditions were determined.Under the optimum reaction conditions,the reaction of trifluoromethyl（acyl）hydrazones and aryl diazo tetrafluoroborate was explored,and the effects of the electronic and spatial effects of the substrates on the reaction were investigated.A series of trifluoromethyl formazan compounds were synthesized with medium to excellent yields.The reaction has the advantages of mild reaction conditions,high yield,good functional group tolerance,simple operation,and good substrate applicability.The experimental results show that trifluoromethyl（acyl）hydrazones can perform coupling reaction at Csp² of imine structure with aryl diazo tetrafluoroborates as an efficient trifluoromethyl building block.Chapter three:Study on the Coupling Reaction Trifluoromethyl Acylhydrazones and Aryldiazonium Tetrafluoroborates under Visible Light PromotionThis chapter explores the coupling reaction of trifluoromethyl（acyl）hydrazones with aryl diazo tetrafluoroborates under photocatalytic conditions.The effects of bases,solvents,material ratio and temperature on the reaction yield were investigated,and the optimum reaction conditions were determined.