Thermal electron-transfer-induced oxidation of 2-pyrazolines

  • Hamid Reza MemarianEmail author
  • Reza Minakar
Original Article


Various 3,5-diaryl-1-phenyl-2-pyrazolines were synthesized, and their thermal oxidation to their corresponding 2-pyrazoles was investigated using tetrabutylammonium peroxydisulfate in acetonitrile solution. Compared to the reported oxidative methods, this oxidizing agent provides a clean and non-expensive oxidative reaction in a short reaction time. Based on the proposed reaction mechanism, the extent of co-planarity of the C3-aryl ring toward C3=N2 double bond of the heterocyclic ring affects the electron-donating ability of the heterocyclic ring and decreases the time of oxidative reaction. The experimental results are supported by cyclic voltammetric measurements.

Graphical abstract


Electron transfer Oxidation Peroxydisulfates 2-Pyrazolines Substituent effects 



We are thankful to the Research Council and Office of Graduate Studies of the University of Isfahan for their financial support.

Supplementary material

11030_2019_9922_MOESM1_ESM.docx (30.1 mb)
Supplementary material 1 (DOCX 30871 kb)


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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Department of ChemistryUniversity of IsfahanIsfahanIslamic Republic of Iran

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