Thermolysis of a coumarin trichloroacetimidate yields a single rearrangement product. The proposed mechanism is a pseudopericyclic allowed (Woodward–Hoffman forbidden) [3,5]-sigmatropic rearrangement to form the corresponding amide followed by a sigmatropic [1,5]-hydrogen migration. Transition state calculations at the B3LYP/6-31G(d,p) level support this mechanism and suggest the selectivity is influenced by the stability of the intermediates.

中文翻译：

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香豆素三氯乙酰亚氨酸酯衍生物的伪周边[3,5]-σ重排

香豆素三氯乙酰亚胺酸酯的热解产生单个重排产物。提出的机制是准周环允许的（伍德沃德-霍夫曼禁用）[3,5]-σ重排形成相应的酰胺，然后发生σ[1,5]-氢迁移。在B3LYP / 6-31G（d，p）水平上的过渡态计算支持该机制，并表明选择性受中间体稳定性的影响。