The nitronium ion, or sometimes the nitryl ion (incorrect because it is not a radical), N O + 2, is a generally reactive cation created by the removal of an electron from the paramagnetic nitrogen dioxide molecule, or the protonation of nitric acid.. The polar mechanism for the nitration of benzene with nitronium ion: ab initio structures of intermediates and transition states. Here nitronium ion (NO2+) acts as an electrophile and reacts with benzene to form nitrobenzene. The nitronium ion is isoelectronic with carbon dioxide and like that compound has a linear structure with a ONO bond angle of 180°. HANTZSCH1 has claimed to have prepared, from anhydrous nitric and perchloric acids, two nitracidium perchlorates, and to have established their compositions by analysis.

[Vernon D Parker, Tapas Kar, Donald Bethell] PMID 23971831 . The rate of nitronium ion formation is the rate-determining step in the nitration of toluene with mixed acid under certain conditions, and values of the rate constant have been determined for the first time. Raman spectroscopic study of nitronium ion formation in mixtures of nitric acid, sulfuric acid and water . The nitronium ion (NO 2 +) and sulfur trioxide (SO 3) are the electrophiles and individually react with benzene to give nitrobenzene and benzenesulfonic acid respectively. It is reactive enough to exist in normal conditions, but it is used extensively as an electrophile in the nitration of other substances. Howell G. M. Edwards, James M. C. Turner and the lateVictor Fawcett Abstract. Nitration of Benzene The source of the nitronium ion is through the protonation of nitric acid by sulfuric acid, which causes the loss of a water molecule and formation of a nitronium ion. HNO3) plus a mineral acid stronger than HNO3. The mechanism of nitration of organic compounds involves electrophilic attack by the nitronium, NO2+, cation, which can exist only in concentrated solutions containing pentavalent N (e.g. Introduction to nitration of benzene Nitration of benzene is an example of elctrophilic aromatic substitution reaction. AROMATIC C-nitration through attack by the nitronium ion was kinetically established by the work of Benford and Ingold1, and of Hughes, Ingold and Reed2. As for example Benzene reacts with concentrated nitric acid in presence of concentrated sulphuric acid as a catalyst, and form nitrobenzene. Abstract The nitration of benzene by nitronium ion in the gas phase has been re-examined.