Palladium-catalyzed C–H glycosylation and retro Diels–Alder tandem reaction <i>via</i> structurally modified norbornadienes (smNBDs)
作者:Yang An、Bo-Sheng Zhang、Ya-Nan Ding、Zhe Zhang、Xue-Ya Gou、Xue-Song Li、Xiaolei Wang、Yuke Li、Yong-Min Liang
DOI:10.1039/d1sc03569j
日期:——
glycosides were applied to the reaction smoothly, and N-alkyl (primary, secondary and tertiary) C4-glycosidic indoles can also be obtained by this method. In terms of mechanism, the key ANP intermediates characterized by X-ray single-crystal diffraction and further controlled experiments proved that the migration-insertion of smNBDs with phenylpalladium intermediate endows them with high chemo- and
本报告描述了钯催化的 C-H 糖基化和通过结构修饰的降冰片二烯 (smNBD) 进行的逆狄尔斯-阿尔德串联反应。smNBDs 被提议用于调节芳基降冰片二烯钯环 (ANP) 的反应性,包括其高化学选择性和区域选择性,这是构建 C2 和 C3 未取代的 C4-糖苷吲哚的关键。这种基材的范围很广;卤代六元和五元糖苷反应顺利,N-烷基(伯、仲和叔)C4-糖苷吲哚也可以通过该方法获得。在机理方面,通过 X 射线单晶衍射表征的关键 ANP 中间体和进一步的受控实验证明,smNBDs 与苯基钯中间体的迁移插入赋予它们高化学和区域选择性。最后,密度泛函理论(DFT)计算进一步验证了该机制的合理性。