作者:Michael E. Jung、Alexandra van den Heuvel、Andrew G. Leach、K. N. Houk
DOI:10.1021/ol0350801
日期:2003.9.1
[structure: see text] Non-aldol aldol rearrangement of the epoxy silyl ether 13b afforded the expected anti methyl ketone 14, while the diastereomeric epoxy silyl ether 13a afforded the syn methyl ketone 8b via an unprecedented syn hydride migration. Calculations suggest that this unusual reaction proceeds via the carbocation, which cannot easily rotate due to steric hindrance.
[结构:见正文]环氧甲硅烷基醚13b的非羟醛缩醛重排提供了预期的抗甲基酮14,而非对映体环氧甲硅烷基醚13a通过前所未有的合成氢化物迁移提供了合成甲基甲酮8b。计算表明,这种异常反应是通过碳正离子进行的,由于位阻,碳正离子不能轻易旋转。