The stereoselective thermal rearrangement of chiral lophine peroxides |
| |
Authors: | Masaru Kimura Gonghao Lu Mitsuru Tsunenaga Zhizhi Hu |
| |
Institution: | a Department of Chemistry, Faculty of Science, Okayama University, Okayama 700-8530, Japan b Department of Applied Chemistry, University of Science and Technology Liaoning, Anshan 114044, PR China |
| |
Abstract: | The thermal reaction of chiral 2-phenyl-4-(p-X-phenyl)-5-(p-Y-phenyl)-4-tert-butyldimethylsilylperoxy-4H-isoimidazoles (5b: X = CF3, Y = OMe; 5c: X = CF3, Y = F) was carried out in DMSO. The chiral 2-phenyl-5-(p-X-phenyl)-5-(p-Y-phenyl)-5H-imidazol-4-ones (4b: X = CF3, Y = OMe; 4c: X = CF3, Y = F) were quantitatively obtained in 50-60% enantiomer excess (ee). The mechanism for the reaction was proved to be stereoselective 1,5-phenyl migration. Although the sigmatropic 1,5-phenyl migration should be thermally allowed according to the Woodward-Hoffmann rule, the migration actually includes a stepwise process. |
| |
Keywords: | 1 5-Sigmatropic migration Lophine peroxide Imidazolone Imidazol-4-ol Rearrangement Stereoselectivity |
本文献已被 ScienceDirect 等数据库收录! |
|