Design And Synthesis Of Pyridoxal / Pyridoxamine Catalyst And Its Application In Asymmetric Catalytic Conversion Of α - Alkyl Ester

Amino acids are a kind of very important organic compounds which are the basic structural units of proteins and vital nutrients for biological organisms. Because of the highly active and extensive use of Amino acid, its synthesis has been attracted much attention. Although there are variety of synthetic methods, such as transition metal catalytic asymmetric hydrogenation, asymmetric alkylation of amino acid derivatives,and asymmetric Strecker reaction, it is still difficult to synthesize chiral amino acids in organic synthesis. Hence, it is important to develop new and efficient methods for the synthesis chiral amino acids.In this thesis, we designed and synthesized a variety of chiral pyridoxal and pyridoxamines. The catalysts exhibited good catalytic activity and promising enantioselective control ability in transamination of α- ketone esters, provided a mild,efficient, and attractive way for the synthesis of optically active amino acid esters.The studies include the following three parts:(1) Design and synthesis of a series of chiral pyridoxal or pyridoxamine catalysts.(2) Investigation of the pyridoxal or pyridoxamine catalysts in asymmetric transamination of α-keto acids and optimization of reaction conditions.(3) Examination of substrate scope under the optimal reaction conditions for the chiral- pyridoxamines-catalyzed asymmetric transamination of keto esters.