Basicity of 2-phenyl-5-R-1,3,4-oxadiazoles

  • R. E. Trifonov
  • V. A. Ostrovskii


We have studied the basicity of 2-phenyl-5-R-1,3,4-oxadiazoles (R = H, Me, CH2Ph, t-Bu, CH2Cl, CCl3, CF3) in aqueous sulfuric acid solutions. These compounds are weak organic bases (pKBH + is −1.8 to −5.2). The values of pKBH + determined on the H0 and X acidity function scales agree well with each other. The substituent at the 5 position has a substantial effect on the basicity of the 1,3,4-oxadiazole ring.


1,3,4-oxadiazoles weak bases basicity UV spectroscopy acidity function electronic substituent constants 


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Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • R. E. Trifonov
    • 1
  • V. A. Ostrovskii
    • 1
  1. 1.St. Petersburg State Technical UniversitySt. PetersburgRussia

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