New Progress in Asymmetric Synthesis of Quaternary α-Amino Acids

Background: Quaternary α-amino acids with a tetrasubstituted carbon stereocenter have a variety of biological activities. Due to the steric hindrance of the quaternary carbon centers, highly efficient asymmetric catalytic synthesis is greatly challenging. Objective: In this paper, with a focus on the asymmetric formation of chemical bonds in reactions, the asymmetric catalytic synthesis of quaternary α-amino acids in recent years is reviewed. Conclusion: Several representative catalytic asymmetric reactions are introduced, and the effects of different catalysts on the reaction results are discussed.