Enantioselective Total Synthesis of Dysiherbols A, C, and D
Enantioselective Total Synthesis of Dysiherbols A, C, and D
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DOI：
10.1021/jacs.2c08435
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发表时间：
2022-10-13
影响因子：
15
通讯作者：
Tang, Yefeng
中科院分区：
文献类型：
--
作者：
Hu, Shengkun;Tang, Yefeng
本文报道了6/6/5/6/6五环醌/对苯二酚倍半萜类化合物A、C和D的对映选择性全合成，以光诱导醌-烯[2 + 2]环加成和[1,2]-阴离子重排/环丙烷裂解为关键元素。基于我们的全合成，我们对原提出的化合物C和D的结构进行了修正。为了深入了解前所未有的[1,2]-阴离子重排，进行了详细的计算研究，结果表明，尽管是一个对称禁止的过程，但由于高环应变能的释放和过渡态局部芳构性的演化，这种转变是通过协调一致的方式进行的。综上所述，本工作提供了一种机制上有趣且综合有用的方法来获取异酚和相关同系物。
Herein, we report the enantioselective total synthesis of dysiherbols A, C, and D, a unique group of 6/6/5/6/6 pentacyclic quinone/hydroquinone sesquiterpenes, featuring a photo-induced quinone-alkene [2 + 2] cycloaddition and a tandem [1,2]-anionic rearrangement/cyclopropane fragmentation as key elements. Based on our total synthesis, the originally proposed structures of dysiherbols C and D have been revised. Detailed computational studies were carried out to gain deep insight into the unprecedented [1,2]-anionic rearrangement, which revealed that the transformation, albeit a symmetry-forbidden process, proceeded through a concerted manner owing to the release of high ring-strain energy and the evolution of local aromaticity in the transition state. Taking all, the present work offers a mechanistically interesting and synthetically useful approach to accessing dysiherbols and related congeners.