Metalated Epoxides as Carbenoids − Further Advances in the Stereospecific Synthesis of Spirocyclopropanes
作者:Luc Dechoux、Claude Agami、Eric Doris、Charles Mioskowski
DOI:10.1002/1099-0690(200111)2001:21<4107::aid-ejoc4107>3.0.co;2-a
日期:2001.11
The intramolecular cyclopropanation of β,γ-unsaturated metalated epoxides derived from 11 yielded the highly strained tricyclic intermediates 7. The facile hydrolysis of the latter species afforded the α-keto spirocyclopropanes 8 in a stereospecific fashion. Indeed, the stereochemistry of the starting alkenes 11d−e governs the relative configuration of the cyclopropanes 8d−e. Furthermore, these spiro
衍生自 11 的 β,γ-不饱和金属化环氧化物的分子内环丙烷化产生高度紧张的三环中间体 7。后一种物质的轻松水解以立体有择的方式提供了 α-酮基螺环丙烷 8。事实上,起始烯烃 11d-e 的立体化学决定了环丙烷 8d-e 的相对构型。此外,这些螺环系统很容易通过各种亲核试剂进行酸介导的开环,从而产生取代的烯酮 12。