Based Organocatalysts in Asymmetric Oxidations

Epoxidation of Enones and a, 3-Unsaturated Sulfones Using Cinchona-Based Chiral Phase-Transfer Catalysts 

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Optically active a-amino acid derivatives are of great importance and have applications in the synthesis of biologically active peptides, natural products and organocatalysts. Based on the concept that catalytic oxidative a-sp C-H bonds of secondary amines provide reactive imines, and considering that the nucleophilic addition to imines has been studied clearly, Wang and coworkers studied the asymmetric CDC reactions of glycine esters with a-substituted ketoesters in the presence of Cu(OTf)2 and a chiral bisoxazoline, obtaining a series of optically active a-allq l a-amino acids and Cl-allq lated THIQs (Scheme 3.22). 

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