β-酮基酯和羟胺环化得到3-羟基-异恶唑（3-异恶唑酚）的反应，称为Claisen异恶唑合成。
由于β-酮基酯有酯基和酮两个反应位点，此反应有个副反应得到5-异恶唑酮：
反应实例
【J. Org. Chem. 2000, 65, 1003-1007】
【J. Med. Chem. 2001, 44, 1051-1059】
相关文献
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编译自：Name Reactions （A Collection of Detailed Reaction Mechanisms）, Jie Jack Li, Claisen isoxazole synthesis， page 138-139.
2022-8-22 摘自 有机合成公众号