Cascade Metathesis Reactions for the Synthesis of Taxane and Isotaxane Derivatives
作者:Cong Ma、Aurélien Letort、Rémi Aouzal、Antonia Wilkes、Gourhari Maiti、Louis J. Farrugia、Louis Ricard、Joëlle Prunet
DOI:10.1002/chem.201600592
日期:2016.5.10
Tricyclic isotaxane and taxane derivatives have been synthesized by a very efficient cascade ring-closing dienyne metathesis (RCDEYM) reaction, which formed the A and B rings in one operation. When the alkyne is present at C13 (with no neighboring gem-dimethyl group), the RCEDYM reaction leads to 14,15-isotaxanes 16 a,b and 18 b with the gem-dimethyl group on the A ring. If the alkyne is at the C11
三环异紫杉烷和紫杉烷衍生物已通过非常有效的级联闭环二烯炔复分解(RCDEYM)反应合成,该反应在一次操作中形成了A和B环。当炔烃存在于C13处(没有相邻的二甲基二甲基)时,RCEDYM反应生成在A环上具有二甲基二甲基的14,15-异紫杉烷16a,b和18b。如果炔烃位于C11位置(并在其旁接有一个二甲基gem基),则RCEDYM反应仅在C13处存在三取代烯烃的情况下进行,这不利于竞争性的二烯闭环易位反应,从而形成三环核紫杉醇44。