Substrate-Controlled Synthesis of Spirocyclopropylpyrazolones and Bicyclic 4,5-Dihydropyrazoles from 1,2-Diaza-1,3-dienes with Sulfur Ylides

作者：Jiaan Shao, Wenteng Chen, Menghao Zhao, Ke Shu, Huan Liu, Pai Tang · 发表于：Organic Letters · 年份：2018 · DOI：10.1021/acs.orglett.8b01562 · 被引用次数：40 · 研究领域：Cyclopropane Reaction Mechanisms、Synthesis and Biological Evaluation、Synthesis and Characterization of Pyrroles

Substrate-controlled reactions have been developed for the synthesis of spirocyclopropylpyrazolones and bicyclic 4,5-dihydropyrazoles from 1,2-diaza-1,3-dienes and sulfur ylides. These protocols were carried out under mild reaction conditions without any additives in generally moderate to good yields. Plausible mechanisms for the transformations were proposed.