One-Pot Two-Step Multicomponent Process of Indole and Other Nitrogenous Heterocycles or Amines toward α‑Oxo-acetamidines

A cesium carbonate promoted three-component reaction of N–H containing heterocycles, primary or secondary amines, arylglyoxaldehydes, and anilines is reported. The key step involves a tandem sequence of N-1 addition of a heterocycle or an amine to preformed α-iminoketones, followed by an air- or oxygen-mediated oxidation to form α-oxo-acetamidines. The scope of the reaction is enticingly broad, and this novel methodology is applied toward the synthesis of various polycyclic heterocycles.本文报道了一种以碳酸铯（cesium carbonate）为促进剂，由含N-H键的杂环（N–H containing heterocycles）、伯胺或仲胺、芳基乙二醛（arylglyoxaldehydes）与苯胺（anilines）参与的三组分反应。该反应的关键步骤为串联过程：杂环或胺的N1位加成至预先形成的α-亚胺酮（preformed α-iminoketones）中间体，随后经空气或氧气介导的氧化（air- or oxygen-mediated oxidation）反应生成α-氧代乙脒（α-oxo-acetamidines）类产物。该反应的底物范围极为广泛，此新型合成方法可应用于多种多环杂环（polycyclic heterocycles）化合物的制备。