Hong Xuechuan, France Stefan, Mejía-Oneto José M, Padwa Albert
Department of Chemistry, Emory University, Atlanta, GA 30322, USA.
Org Lett. 2006 Oct 26;8(22):5141-4. doi: 10.1021/ol062029z.
An approach to the hexacyclic framework of the kopsifoline alkaloids has been developed and is based on a Rh(II)-catalyzed cyclization-cycloaddition cascade. The resulting [3+2]-cycloadduct was readily converted into the TBS enol ether 23. Oxidation of the primary alcohol present in 23 followed by reaction with CsF afforded compound 24 that contains the complete hexacyclic skeleton of the kopsifolines. [reaction: see text]
已经开发出一种构建柯蒲木碱六环骨架的方法,该方法基于铑(II)催化的环化-环加成串联反应。所得的[3+2]环加成产物很容易转化为叔丁基二甲基硅烷基(TBS)烯醇醚23。对23中存在的伯醇进行氧化,然后与氟化铯反应,得到含有柯蒲木碱完整六环骨架的化合物24。[反应:见原文]