A variety of 3‐substituted and 2,3‐disubstituted indoles were synthesized efficiently in good yields through the intramolecular amination of 2‐alkenylanilines promoted by readily available iodine(III) reagents in a short reaction time. Mechanistic studies showed that the reaction pathway went through a nitrenium ion and that 3‐acetoxy indoline was the key intermediate in the indole formation. The indole product was easily prepared on a gram scale and amination also proceeded smoothly using catalytic 3,5‐dimethylphenyl iodine in the presence of mCPBA. Furthermore, the indolo[3,2‐a]carbazole scaffold was prepared in good yield in six steps from commercial ortho‐iodoaniline.

中文翻译：

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碘（III）试剂介导的2-烯基苯胺分子内胺化反应以制备吲哚

通过在很短的反应时间内即可获得的碘（III）试剂促进的2-烯基苯胺的分子内胺化反应，可以高收率高效合成各种3-取代和2,3-二取代的吲哚。机理研究表明，反应路径通过一个氮离子，3-乙酰氧基吲哚是吲哚形成的关键中间体。吲哚产物很容易以克为单位制备，并且在m CPBA存在下，使用催化的3,5-二甲基苯基碘也可以顺利进行胺化反应。此外，吲哚并[3,2-a]咔唑支架的制备要比市售邻碘碘苯胺分6步高收率。