报道了两种高烯丙基卤化物的简洁有效的合成方法,它们是制备紫杉烷 A 环系统的有用前体。与文献中报道的合成路线相反,该方法不使用昂贵的四甲基乙烯作为起始材料。该合成路线使用容易获得且廉价的乙酰乙酸乙酯、1,2-二溴乙烷、甲基三苯基碘化鏻和甲基溴化镁作为起始原料。合成的关键步骤是酸介导的环丙基叔醇开环,得到相应的高烯丙基二烯卤化物。衍生自溴化物的相应格氏试剂用于通过与 1,3-环己二酮的烯醇乙醚反应合成先前用作紫杉二烯酮前体的烯酮。
Stereoselective Synthesis of the Taxane Ring System via the Tandem Diels−Alder Cycloaddition
作者:Jeffrey D. Winkler、Hak Sung Kim、Sanghee Kim、Kaori Ando、Kendall N. Houk
DOI:10.1021/jo961620e
日期:1997.5.1
The application of the tandem Diels-Alder cycloaddition to the stereoselectivesynthesis of the tricyclic ring system of the taxane diterpenes is described. The exceedingly direct, two-step synthesis of the B/C cis-fused taxane nucleus in 50% overall yield from the reaction of two readily available acyclic precursors underscores the efficiency of this approach. A critical feature of the second, intramolecular