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An Efficient Catalytic Asymmetric Epoxidation Method

Zhi-Xian Wang, Yong Tu, Michael Frohn, Jian-Rong Zhang and Yian Shi*

*Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, Email: yianlamar.colostate.edu

Z.-X. Wang, Y. Tu, M. Frohn, J.-R. Zhang, Y. Shi, J. Am. Chem. Soc., 1997, 119, 11224-11235.

DOI: 10.1021/ja972272g (free Supporting Information)


Abstract

A highly effective catalytic asymmetric epoxidation method allows the conversion of trans-disubstituted and trisubstituted olefins using potassium peroxomonosulfate (Oxone) as oxidant and a fructose-derived ketone as catalyst with high enantioselectivies. Functional groups such as tributylsilyl ether, acetal, chloride, and ester are tolerated. Enantiomeric excesses for cis-olefins and terminal olefins are not high yet.

see article for more examples

proposed transition state



Highly Enantioselective Epoxidation of cis-Olefins by Chiral Dioxirane

H. Tian, X. She, L. Shu, H. Yu, Y. Shi, J. Am. Chem. Soc., 2000, 122, 11551-11552.

Asymmetric Epoxidation of 1,1-Disubstituted Terminal Olefins by Chiral Dioxirane via a Planar-like Transition State

B. Wang, O. A. Wong, M.-X. Zhao, Y. Shi, J. Org. Chem., 2008, 73, 9539-9543.


Key Words

Epoxides, Organocatalysis, Oxone, Shi Epoxidation


ID: J48-Y1997-750