Site-selective amination towards tertiary aliphatic allylamines
Site-selective amination towards tertiary aliphatic allylamines
复制标题
针对脂肪族烯丙胺的位点选择性胺化
作者：
Shengchun Wang;Yiming Gao;Zhaoiun Liu;Demin Ren;He Sun;Linbin Niu;Dali Yang;Dongchao Zhang;Xingan Liang;Renyi Shi;X. Qi;A. Lei
脂肪族烯丙胺被广泛用于合成农用化学品和医药的各种构件；因此，人们对利用常见的化学原料--烯烃和胺开发合成脂肪族烯丙胺的多种直接路线很感兴趣。然而，这种偶联反应的例子仍然有限。通过精确的现场控制来实现这一目标甚至更具挑战性。在这里，我们报告了光催化剂和钴肟的结合，使烯烃与仲烷基胺的位置选择性胺化得到烯丙基胺，从而消除了对氧化剂的需求。这种方法与广泛的烯烃相容，并且可以扩展以实现萜烯的位置选择性和非对映选择性的胺化。机理研究揭示，反应通过钴肟促进的氢原子转移途径进行，得到的产物是较强的伯烯丙基C-H键相对于其他较弱的烯丙基C-H键的裂解产物。未活化的烯烃与脂肪胺的烯丙胺化反应是有机化学中一个长期存在的合成难题。现在，这是通过使用光催化剂和钴络合物的组合来实现的，该过程无需氧化剂，具有位置选择性，用于烯烃和烷基胺的偶联放氢。
Aliphatic allylamines are widely used for the synthesis of diverse building blocks for agrochemicals and pharmaceuticals; there is therefore considerable interest in developing versatile and direct routes to aliphatic allylamines using common chemical feedstocks—olefins and amines. However, examples of such coupling reactions remain limited. It is even more challenging to achieve this goal with precise site control. Here we report that the combination of a photocatalyst and cobaloxime enables site-selective amination of olefins with secondary alkyl amines to afford allylic amines, eliminating the need for oxidants. This method is compatible with a broad scope of olefins and can be extended to achieve a site- and diastereoselective amination of terpenes. Mechanistic studies disclose that the reaction proceeds via a cobaloxime-promoted hydrogen atom transfer pathway to afford the product that results from cleavage of the stronger, primary allylic C–H bonds over other weaker allylic C–H bond options. Allylic amination of unactivated alkenes with aliphatic amines is a long-standing synthetic challenge in organic chemistry. This is now accomplished in an oxidant-free, site-selective process by using a combination of a photocatalyst and cobalt complex for the coupling of olefins and alkyl amines with hydrogen evolution.
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影响因子：
15
作者：
Dian Wang;Karina Targos;Zachary K. Wickens
通讯作者：
Dian Wang;Karina Targos;Zachary K. Wickens
影响因子：
15
作者：
Reed, Sean A.;Mazzotti, Anthony R.;White, M. Christina
通讯作者：
White, M. Christina
影响因子：
15
作者：
Pattillo CC;Strambeanu II;Calleja P;Vermeulen NA;Mizuno T;White MC
通讯作者：
White MC
影响因子：
12.9
作者：
Ganley JM;Murray PRD;Knowles RR
通讯作者：
Knowles RR