含活泼亚甲基的酯在碱金属盐存在下，DMSO中脱除烷氧羰基。该反应可取代乙酰乙酸乙酯合成法和丙二酸酯合成法中最后酯的水解和脱羧两步反应。值得一提的是，Krapcho反应是一意外发现，原先的目的是用KCN进行Sn2取代反应，缺意外的得到部分氧羰基脱除产物。后来反现碱金属LiI，LiCl，KCN，NaCN，LiCN均可用于这个反应。

反应机理

反应实例

参考文献

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摘自：有机人名反应——机理及应用 第四版，Strategic Applications of Named Reactions in Organic Synthesis