Definition of diazonium in English:



  • [as modifier] An organic cation containing the group —N2+ bonded to an organic group. Aromatic diazonium compounds are typically intensely coloured and include many synthetic dyes:

    ‘a diazonium salt’
    ‘diazonium chloride’
    • ‘Phenol can be produced from aniline by reacting aniline with a mixture of sodium nitrite and hydrochloric acid to give benzene diazonium chloride, that when heated gently, gives off nitrogen to leave phenol.’
    • ‘R2 contains 3 mmol / L of diazonium ion and 100 mmol / L of hydrochloric acid.’
    • ‘The manufacture of PY74 would most likely occur through diazotization of 2-amino - 5-nitroanisole to the corresponding diazonium salt and condensation of the diazonium salt with o-acetoacetanisidide.’
    • ‘These nitrites then react to form a diazonium salt which in turn reacts with a chromogen to produce the final color.’


Late 19th century: coined in German from diazo- (indicating the presence of two nitrogen atoms) + the suffix -onium (from ammonium).