A novel Brønsted acid promoted condensation reaction between a primary aniline and 2-hydroxycyclobutanone provides access to diverse tryptamine derivatives in moderate to good yields. The proposed mechanism involves an α-iminol rearrangement, ring expansion, ring closure, and a depart-and-return rearrangement process.

中文翻译：

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通过瞬时2-取代的2-羟基环丁基亚胺的α-亚氨基重排引发的新型布朗斯台德酸介导的串联反应合成色胺

一种新颖的布朗斯台德酸促进伯胺与2-羟基环丁酮之间的缩合反应，可提供中等至良好收率的多种色胺衍生物。所提出的机制涉及α-亚氨基重排，环的扩展，环的闭合以及离去和返回的重排过程。