Diastereoselective epoxidation of various camphor-derived enones with different oxidants: Reversal of stereoselectivity

ORGN 460

Kwunmin Chen, Wei-Der Lee, Chai-Ling Fan, Ching-Chen Chiu, and Hua-Lin Hsu. Department of Chemistry, National Taiwan Normal University, 88 sec. 4 TingChow Road, Taipei, 116, Taiwan

Treatment of various camphor-derived enones with different oxidants afford the corresponding epoxides with high material yields in good to excellent diastereoselectivity (up to >95% de). Both diastereomeric isomers of epoxides with high optical purity are obtained when camphorsultam (1) and camphorpyrazolidinone (2) derived enones are treated with an urea hydrogen peroxide/TFAA and methyl(trifluoromethyl)dioxirane, respectively. One of the major goals was to determine the scope of the epoxidation with respect to substituent tolerance on the chiral auxiliaries. The stereochemical bias will be presented.

Total Synthesis, Asymmetric Reactions and Syntheses, Bioorganic 9:00 AM-11:00 AM, Wednesday, March 31, 2004 Anaheim Convention Center -- Hall C, Poster Sci-Mix 8:00 PM-10:00 PM, Monday, March 29, 2004 Anaheim Convention Center -- Hall A, Sci-Mix Division of Organic Chemistry The 227th ACS National Meeting, Anaheim, CA, March 28-April 1, 2004