Asymmetric Epoxidation of 1,1-Disubstituted Terminal Olefins by Chiral Dioxirane via a Planar-like Transition State
Bin Wang, O. Andrea Wong, Mei-Xin Zhao and Yian Shi*
*Department of Chemistry, Colorado State University, Fort
Collins, Colorado 80523, Email: yianlamar.colostate.edu
B. Wang, O. A. Wong, M.-X. Zhao, Y. Shi, J. Org. Chem., 2008, 73, 9539-9543.
DOI: 10.1021/jo801576k
Abstract
Up to 88% ee has been achieved for asymmetric epoxidation of 1,1-disubstituted terminal olefins using a chiral lactam ketone as catalyst. A planar transition state is likely to be a major reaction pathway.
see article for more examples
proposed transition state
An Efficient Catalytic Asymmetric Epoxidation Method
Z.-X. Wang, Y. Tu, M. Frohn, J.-R. Zhang, Y. Shi, J. Am. Chem. Soc., 1997, 119, 11224-11235.
Highly Enantioselective Epoxidation of cis-Olefins by Chiral Dioxirane
Z.-X. Wang, Y. Tu, M. Frohn, J.-R. Zhang, Y. Shi, J. Am. Chem. Soc., 1997, 119, 11224-11235.
Key Words
Epoxides, Organocatalysis, Oxone, Shi Epoxidation
ID: J42-Y2008-3660