Home – Home – Jornals – Chemistry for Sustainable Development 2022 number 6

Mass spectrometric characteristics of N-alkyl-4-nitro-1,2,3-triazoles were investigated using a gas chromatograph with a quadrupole mass spectrometric detector in the mode of electron ionization (70 eV). The stability of the molecular ion was studied depending on the position, structure and nature of the alkyl substituent at the endocyclic nitrogen atoms of nitrotriazole heterocycle. N2-alkyl-4-nitro-1,2,3-triazoles were found to have the highest stability and molecular ion intensity, independently of the alkyl substituent in the structure of the compound. The pathways of molecular ion fragmentation are proposed for the compounds under consideration, and characteristic ions are identified. Molecular ion fragmentation in N-alkyl-4-nitro-1,2,3-triazoles was discovered to start with the elimination of the exocyclic NO₂ group, followed by detachment of the respective alkyl substituent and generation of the cation radical of 1,2,3-triazole. Fragmentation of non-substituted cation radical of 1,2,3-triazole proceeds through characteristic detachment of N atom or neutral molecules N₂ and HCN. In turn, the ionic decay of bulky alkyl substituents (cyclohexyl and benzyl radicals) leads to a group of characteristic ions with high relative intensity. In general, the findings demonstrate that mass spectrometry can be efficiently used for robust identification of structural isomerism ( N1-, N2- and N3-isomers) of alkyl-4-nitro-1,2,3-triazoles and the products of their decomposition.