Highly Enantioselective Epoxidation of α,β-Unsaturated Ketones Catalyzed by Rare-Earth Amides [(Me3Si)2N]3RE(μ-Cl)Li(THF)3 with Phenoxy-Functionalized Chiral Prolinols
Chao Zeng, Dan Yuan, Bei Zhao* and Yingming Yao*
*College of Chemistry, Chemical Engineering and Materials Science, Dushu Lake Campus, Soochow University, Suzhou 215123, People's Republic of China, Email: zhaobeisuda.edu.cn, yaoymsuda.edu.cn
C. Zeng, D. Yuan, B. Zhao, Y. Yao, Org. Lett., 2015, 17, 2242-2245.
A simple and efficient enantioselective epoxidation of α,β-unsaturated ketones is catalyzed by rare-earth metal amides in the presence of phenoxy-functionalized chiral prolinols at room temperature using tert-butylhydroperoxide (TBHP) as the oxidant. The combination of an Yb-based amide and a chiral proligand provided chiral epoxides in excellent yields and enantiomeric excess of up to 99%.
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Asymmetric Epoxidation of Unsaturated Ketones Catalyzed by Heterobimetallic Rare Earth-Lithium Complexes Bearing Phenoxy-Functionalized Chiral Diphenylprolinolate Ligand
Q. Qian, Y. Tan, B. Zhao, T. Feng, Q. Shen, Y. Yao, Org. Lett., 2014, 16, 4516-4519.