Enantioselective Synthesis Of Phenylalanine Derivatives By Direct C–H Oxidative Cross-coupling

Chiralα-amino acid derivatives have various and special structures as well as widely application value.Therefore,they are employed in theelaboration of peptides and proteins as chiralcatalysts andas chiral pool in the ligand design and total synthesis.The historical overview about the elaboration ofenantiopure chiralα-amino acid derivatives can be classified into three periods.First, chiralα-amino acid derivatives can be isolated throughchemical and enzymatic resolutionsfrom natural sources. Second,thediastereoselective synthesis of chiralα-amino acid derivatives, based on the design of chiral templates derived from glycine, alanine, andother chiralα-amino acid derivatives. Finally, catalytic enantioselective methods have been overwhelmingly preferred, and used to synthesis of chiralα-amino acid derivatives. This thesis describes the studies on the enantioselective synthesis of phenylalanine derivatives by direct C–H oxidative cross-coupling and nucleophlic addition reactions.According to the contents of our study, this thesis can be concluded astwo parts:Chapter 1. This chapter mainly introduces the methods of enantioselective synthesis of chiralα-amino acid derivatives, including asymmetric hydrogenation of α-imino esters and enamine, nucleophlic addition reactions between nucleophilic reagent and α-imino esters, reductive amination ofα-keto acids andα-keto esters,asymmetric Strecker-type reactions.Chapter 2. The enantioselective synthesis of phenylalanine derivatives by direct C–H oxidative cross-coupling.Under the action of transition metal catalyst, the enantioselective synthesis of phenylalanine derivatives by direct C–H oxidative cross-coupling and nucleophlic addition reactions that are implemented. The method is compatible with the oxidation and nucleophlic addition system. Reaction havesaveral features, including widely source of substrate, simple operation,with optical activity.The method for the synthesis ofα-amino acid derivatives provide a novel flexible way. The new method as a new power is injected into the dynamic asymmetric research field.