Abstract When we used 2-ferrocenethynylaniline (1a) as reactant and NaAuCl4·2H2O (5%) as catalyst to prepare 2-ferrocenylindole (2a), we were surprised to find that 3,3′-ferrocenylbiindole (3a) was obtained simultaneously. 3a was characterized by elemental analysis, FT-IR, MS, NMR, and X-ray single crystal diffraction. The reactant substitution reaction, in-situ HNMR, XPS, EPR characterization, and calculations were carried out to interpret why 3a was obtained in one pot. The results showed that the hydroperoxyl radical played a key role in the reaction, which induced synthesis of 3a. Graphical Abstract

中文翻译：

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二茂铁诱导一锅法合成 3,3'-二茂铁二吲哚

摘要 当我们以 2-二茂铁基苯胺 (1a) 为反应物和 NaAuCl4·2H2O (5%) 为催化剂制备 2-二茂铁基吲哚 (2a) 时，我们惊讶地发现同时获得了 3,3'-二茂铁基二吲哚 (3a)。通过元素分析、FT-IR、MS、NMR和X射线单晶衍射表征了3a。进行了反应物取代反应、原位 HNMR、XPS、EPR 表征和计算，以解释为什么在一锅中获得 3a。结果表明，氢过氧自由基在该反应中起关键作用，诱导了 3a 的合成。图形概要