Properties of 4-nitrosopyrazoles with perfluoroalkyl substituent

The paper investigates the structure and physicochemical properties of nitrosopyrazoles with perfluoroalkyl substituents. The authors pay special attention to the effect of fluorine atoms on the physicochemical properties of compounds and their acidity. IR spectroscopy confirms the existence of the dimer of 4-nitrosopyrazoles. In establishing the structure of the mass spectrum fragmentation ions, we assumed an aziridine rearrangement accompanying the decomposition of the compounds. The authors determined pKa for the synthesised hydroxyimino-β-diketones and nitrosopyrazoles by spectrophotometric method. Moreover, the authors determined the optical density of the solutions on a spectrophotometer and the acidity constant by graphical and analytical methods