Two epimeric pairs of N‐Ts‐protected cyclohexylamines that incorporate an unsaturated side‐chain at the C2 position have been prepared. Contrary to expectations, none of these underwent clean, photochemically‐induced intramolecular hydroamination reactions to give the corresponding perhydro‐indole or ‐quinolines. However, they did participate in efficient olefin cross metathesis (OCM) reactions with methyl crotonate. Three of the four acrylates so‐formed engaged in base‐promoted and completely diastereoselective, intramolecular aza‐Michael addition (cyclisation) reactions to give the isomeric and C2‐substituted perhydro‐indoles or ‐quinolines with the structures of these being confirmed by single‐crystal X‐ray analyses. DFT calculations generated results consistent with the observed diastereoselectivities and the proposed transition states. Manipulation of the ester groups associated with the cyclization products allowed for their conversion, inter alia, into the corresponding n‐propyl residues and thus providing novel analogues of neurotoxic alkaloids such as pumiliotoxin C.

中文翻译：

---

C2位不饱和侧链氨基环己烷衍生物的合成及闭环反应。


已制备出两对 N-Ts 保护的环己胺的差向异构体，它们在 C2 位上包含不饱和侧链。与预期相反，这些都没有经历干净的、光化学诱导的分子内氢胺化反应以产生相应的全氢吲哚或喹啉。然而，它们确实参与了与巴豆酸甲酯的有效烯烃交叉复分解（OCM）反应。如此形成的四种丙烯酸酯中的三种参与碱促进和完全非对映选择性的分子内氮杂迈克尔加成（环化）反应，得到异构体和C2取代的全氢吲哚或喹啉，这些结构通过单-证实晶体X射线分析。 DFT 计算生成的结果与观察到的非对映选择性和提出的过渡态一致。对与环化产物相关的酯基进行操作，可以将其转化为相应的正丙基残基，从而提供神经毒性生物碱（例如普米里奥毒素 C）的新型类似物。