Johnson–Claisen原乙酸酯重排

在少量弱酸存在下，加热烯丙醇类化合物与过量的原乙酸三酯反应得到γ,δ-不饱和酯的反应。

反应机理

机理同Claisen重排（Claisen重排反应），原乙酸酯先和烯丙醇反应生成原乙酸混酯，其失去一个醇得到乙烯缩醛，接着发生[3,3]-σ单电子重排得到γ,δ-不饱和酯。

反应实例

【 J. Am. Chem. Soc. 1987, 109, 3025–3036】.

【 J. Org. Chem. 1993, 58, 4280–4286】.

【Angew. Chem. Int. Ed. 1998, 37, 2085–2087】.

【Bioorg. Med. Chem. Lett. 2005, 15, 1647–1650】.

【Org. Lett. 2008, 10, 681–684】 .

Johnson, W. S.; Werthemann, L.; Bartlett, W. R.; Brocksom, T. J.; Li, T.-t.; Faulkner, D. J.; Peterson, M. R. J. Am. Chem. Soc. 1970, 92, 741. William S. Johnson (1913-1995) was born in New Rochelle, New York. He earned his Ph.D. in only two years at Harvard under Louis Fieser. He was a professor at the University of Wiscon sin for 20 years before moving to Stanford University, where he was credited with building the modern-day Stanford Chemistry Department.

参考文献：

Name Reactions （A Collection of Detailed Reaction Mechanisms）, Jie Jack Li, Johnson–Claisen orthoester rearrangement, page 150-151.