Chinese Journal of Organic Chemistry ›› 2024, Vol. 44 ›› Issue (9): 2832-2840.DOI: 10.6023/cjoc202404017 Previous Articles     Next Articles

ARTICLES

硫氰酸铵促进的[3+3]环化反应合成5-芳基吡唑并[1,5-a]嘧啶

李龙龙a, 何欣悦a, 周龙生a, 曲亨通a, 冯承涛a,*(), 徐坤b,*()   

  1. a 安徽中医药大学药学院 合肥 230012
    b 北京工业大学化学与生命科学学院 北京 100124
  • 收稿日期:2024-04-11 修回日期:2024-05-07 发布日期:2024-05-23
  • 通讯作者: 冯承涛, 徐坤
  • 基金资助:
    安徽省自然科学基金(2008085MB50); 及安徽省高校自然科学研究重点(KJ2021A0598)

NH4SCN-Promoted Formal [3+3] Annulation for the Synthesis of 5-Arylated Pyrazolo[1,5-a]pyrimidines

Longlong Lia, Xinyue Hea, Longsheng Zhoua, Hengtong Qua, Chengtao Fenga(), Kun Xub()   

  1. a School of Pharmacy, Anhui University of Chinese Medicine, Hefei 230012
    b College of Chemistry and Life Science, Beijing University of Technology, Beijing 100124
  • Received:2024-04-11 Revised:2024-05-07 Published:2024-05-23
  • Contact: Chengtao Feng, Kun Xu
  • Supported by:
    Anhui Provincial Natural Science Foundation(2008085MB50); Education Bureau of Anhui Province(KJ2021A0598)

A formal [3+3] annulation of 3-aminopyrazoles with cinnamaldehydes or cinnamyl alcohols mediated by NH4SCN has been developed. This protocol provides a practical route to construct 5-arylated pyrazolo[1,5-a]pyrimidines with high functional group tolerance. The use of NH4SCN as the cyanide anion surrogate allows the transient generation of cyanohydrin, which shifts the reactive center within cinnamaldehydes from formyl group to alkene group to realize an opposite regiocontrol comparing with previous reports.

Key words: tandem cyclization, hypervalent iodine, regioselectivity, pyrazolo[1,5-a]pyrimidine, cinnamaldehyde