Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA.
Angew Chem Int Ed Engl. 2019 May 6;58(19):6385-6390. doi: 10.1002/anie.201813960. Epub 2019 Mar 14.
Direct amination of C(sp )-H bonds is of broad interest in the realm of C-H functionalization because of the prevalence of nitrogen heterocycles and amines in pharmaceuticals and natural products. Reported here is a combined electrochemical/photochemical method for dehydrogenative C(sp )-H/N-H coupling that exhibits good reactivity with both sp and sp N-H bonds. The results show how use of iodide as an electrochemical mediator, in combination with light-induced cleavage of intermediate N-I bonds, enables the electrochemical process to proceed at low electrode potentials. This approach significantly improves the functional-group compatibility of electrochemical C-H amination, for example, tolerating electron-rich aromatic groups that undergo deleterious side reactions in the presence of high electrode potentials.
直接胺化 C(sp ）-H 键在 C-H 官能化领域具有广泛的兴趣，因为氮杂环和胺在药物和天然产物中很常见。本文报道了一种电化学/光化学联合方法，用于脱氢 C(sp ）-H/N-H 偶联，该方法对 sp 和 sp N-H 键均具有良好的反应性。结果表明，使用碘化物作为电化学介体，并结合光诱导中间 N-I 键的断裂，如何使电化学过程能够在低电极电势下进行。这种方法显著提高了电化学 C-H 胺化的官能团兼容性，例如，容忍富电子芳基，这些芳基在高电极电势存在下会发生有害的副反应。
