example of oxyamination of azlactones with oxaziridines was realized using a chiral bisguanidinium salt. Efficient catalytic asymmetric oxyamination and kinetic resolution of oxaziridines occurred simultaneously. Various chiral oxazolin-4-one derivatives with potential biological activity were obtained (up to 92% ee). Meanwhile, a series of optically pure oxaziridines were recovered with up to 99% ee and
Chirality transformation is a basic, attractive, and important strategy for obtaining enantioenriched products with desired chiral elements. The reported chirality conversion reaction often involves the process from one type of chirality to another one. To better utilize the chirality transformation strategy for obtaining two or more products with different chiral elements in a single reaction, a new
Kinetic Resolution of Oxaziridines via Chiral Bifunctional Guanidine-Catalyzed Enantioselective α-Hydroxylation of β-Keto Esters
作者:Xiaobin Lin、Sai Ruan、Qian Yao、Chengkai Yin、Lili Lin、Xiaoming Feng、Xiaohua Liu
DOI:10.1021/acs.orglett.6b01614
日期:2016.8.5
efficient kinetic resolution of racemic oxaziridines has been realized via catalytic asymmetric α-hydroxylation of available β-ketoesters. In the presence of a chiral bifunctional guanidine catalyst, a variety of optically active oxaziridines and chiral α-hydroxy β-ketoesters were generated with excellent results (ee’s of up to 99% and 97% and yields of up to 44% and 54%, respectively).
Lewis Acids Promoted 3 + 2 Cycloaddition of Oxaziridines and Cyclic Allylic Alcohols through Carbonyl Imine Intermediates
作者:Erbao Zhao、Feilong Zhou、Yujun Zhao
DOI:10.1021/acs.joc.9b00246
日期:2019.4.5
Syntheses of isoxazolidines through the carbonyl imine intermediates are currently limited to monosubstituted olefin substrates. Herein, we reported syntheses of novel bicyclic isoxazolidine-containing compounds through 1,3-dipolar cycloaddition reactions using cyclic allylicalcohols as substrates, which proved challenging in previous reports. Generally, the reaction yields range from good to high