作者:Patrick Zimdars、Yuzhou Wang、Peter Metz
DOI:10.1002/chem.202100560
日期:2021.5.20
intramolecular Diels-Alder reactions were applied to generate the tricyclic core. A chemoselective Mitsunobu inversion of a syn 1,2-diol allowed for further streamlining of the original reaction sequence by two steps. Overall, (−)-salvinorin A was synthesized in only 16 steps starting from 3-furaldehyde with 1.4 % total yield. Furthermore, an alternative intramolecular Diels-Alder strategy employing a 2-bromo-1
报道了新克罗丹二萜 (−)-salvinorin A 的简明对映选择性全合成。C-12处的立体中心是通过催化不对称炔丙基化安装的,具有优异的对映选择性,其余六个立体中心在底物控制下高度非对映选择性地建立。至于我们之前合成的外消旋Salvinorin A,应用了两个分子内Diels-Alder反应来生成三环核心。顺式1,2-二醇的化学选择性 Mitsunobu 反转允许通过两个步骤进一步简化原始反应序列。总体而言,从 3-糠醛开始,仅经过 16 个步骤即可合成 (−)-salvinorin A,总产率为 1.4%。此外,还研究了采用 2-溴-1,3-二烯部分的替代分子内 Diels-Alder 策略。