Department of Chemistry, IIT Guwahati, 781039, India.
Chem Commun (Camb). 2020 Mar 12;56(21):3167-3170. doi: 10.1039/c9cc09616g.
Traditionally, amines react with nitrosoarenes to provide the corresponding imines or azo compounds. Herein, we report an acid mediated annulation reaction of aliphatic amines and nitrosoarenes to provide indole derivatives. The elusive direct annulation of aliphatic amines and nitrosoarenes via simultaneous C-C and C-N bond formation was achieved under metal free conditions. This conceptually novel method for indole synthesis does not require pre-functionalization steps for the new C-C and C-N bond formation. The method has been applied for an elegant synthesis of nor-neocryptolepine and neocryptolepine.
传统上，胺与亚硝基芳烃反应生成相应的亚胺或偶氮化合物。在此，我们报告了一种酸介导的脂肪胺和亚硝基芳烃的环化反应，可提供吲哚衍生物。在无金属条件下，通过同时形成 C-C 和 C-N 键，实现了脂肪胺和亚硝基芳烃难以直接环化的反应。这种通过新的 C-C 和 C-N 键形成的概念新颖的吲哚合成方法不需要预官能化步骤。该方法已应用于去甲新隐丹参碱和新隐丹参碱的优雅合成。
