Study On Functionalization Of P-H Bond Catalyzed By Metal/Chiral Selenium

Organophosphorus compounds are powerful compounds with a wide range of applications in biological activities,natural products,pharmaceuticals,agricultural chemicals and organic chemical materials,as well as as ligands in catalysis.The preparation of these compounds requires synthesis techniques with novel catalytic systems,ranging from transition metal,photoand electrochemical catalysis to conversion without metal catalysts.Organophosphorus chemistry is a mature and professional field.We hope to develop new methods for the synthesis of organophosphorus compounds and play a positive role in the development of organophosphorus chemistry.Secondary phosphine oxide(SPO)is an important organophosphorus compound,which has the advantages of good stability,low toxicity,odorless and so on.Meanwhile,as a highly active substance,various organophosphorus compounds are constructed by P-H bond functionalization through metal catalysis,photocatalysis,electrochemistry and small molecule catalysis.This thesis mainly focuses on the design of secondary phosphine oxides to develop some synthetic methods,the main content includes the following chapters:Chapter 1: The research progress of P-H bond functionalization of secondary phosphine oxides was summarized.In organophosphorus chemical synthesis methodology,the construction of organophosphorus compounds through the P-H bond of secondary phosphine oxides is an important strategy.Secondary phosphine oxides,as reaction substrates,participate in transition metal-promoted cross-coupling reactions,addition reactions between P-H bonds and unsaturated bonds,radical reactions,and construction of chiral phosphine compounds.Chapter 2: We developed a new method for the esterification and hydroxylation of secondary phosphine oxides via P-H/C-H tandem cyclization to generate dibenzoxyphosphorus.The process showed good functional group tolerance,and the corresponding products were obtained with high yield and selectivity.This reaction will provide an effective method for the synthesis of different functionalized dibenzophosphorus oxides.Chapter 3: Since the following work involves the catalysis of organic small molecules with chiral selenium,this chapter introduces various important synthetic organic transformations promoted by achiral and chiral organic selenium catalysts.Several chiral organic selenium catalysts were studied to achieve different stereoselective reactions.Chapter 4: We developed a chiral selenium-catalyzed asymmetric N-P coupling of secondary phosphine oxides and amines to construct P-chiral phosphoramide compounds.Through intermolecular cross-dehydrogenation coupling,the reaction conditions are simple and mild,and the substrate is suitable for a wide range,which is a new method with high atom economy and green.It provides a new strategy for the construction of a wide range of P-chiral phosphoramide compounds and a new idea for the fields of asymmetric catalysis and drug development.