An efficient synthesis of N-acetyl-2-substituted indole derivatives via direct intramolecular hydroamination of N-acetyl-2-alkynylaniline derivatives was developed. The reaction could be applied to a wide range of substrates employing only 1–2 mol% of PtCl₄ as the catalyst to furnish the desired indole products in moderate to excellent yields. The current protocol is efficient, reliable and scalable, and could serve as an important tool for convenient and rapid access to this important class of N-heterocyclic skeleton from readily available substrates.

中文翻译：

---

PtCl ₄催化的N-乙酰基-2-炔基苯胺的环化反应：N-乙酰基-2-取代的吲哚的温和而有效的合成

通过N-乙酰基-2-炔基苯胺衍生物的直接分子内加氢胺化反应，开发了一种N-乙酰基-2-取代的吲哚衍生物的有效合成方法。该反应可应用于仅使用1-2 mol％的PtCl ₄作为催化剂的各种各样的底物，以中等至极好的收率提供所需的吲哚产物。当前的协议是有效，可靠和可扩展的，并且可以用作从容易获得的底物方便且快速地访问这一重要的N-杂环骨架类的重要工具。