Chin. J. Org. Chem. ›› 2016, Vol. 36 ›› Issue (3): 520-526.DOI: 10.6023/cjoc201509020 Previous Articles     Next Articles



李玉峰, 黄佳维, 顾嘉超, 黄浩, 钮长盛, 马鸿飞   

  1. 南京工业大学化学与分子工程学院 南京 211816
  • 收稿日期:2015-09-18 修回日期:2015-11-12 发布日期:2015-12-07
  • 通讯作者: 李玉峰

Sequential Three-Component Reactions for the Assembly of Functionalized Pyrazoles

Li Yufeng, Huang Jiawei, Gu Jiachao, Huang Hao, Niu Changsheng, Ma Hongfei   

  1. College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816
  • Received:2015-09-18 Revised:2015-11-12 Published:2015-12-07

A sequential three-component reaction for the assembly of functionalized pyrazoles is described. Aldehydes are treated with hydrazines in dichloroethane to generate hydrazones (3), which in situ take place aza-Michael reaction quickly with methyl propiolate (4) catalyzed by CuCl to give Michael adducts (5). Subsequent oxidation of 5 with stoichiometric FeCl3 provides substituted pyrazoles with high to excellent yields. The intermediates of the synthetic method are not necessary to isolate. Aliphatic hydrazines, aromatic hydrazines as well as aromatic aldehydes are well adaptable to the reaction.

Key words: hydrazine, aldehyde, methyl propiolate, pyrazoles, three-component reaction