nitronium

nitronium

[nī′trō·nē·əm]
(chemistry)
Positively charged NO2 ion, believed to be formed from HNO3. Also known as nitryl ion.
References in periodicals archive ?
7 There are numerous types of free radicals that can be formed within the biological system, but the most common types are: reactive oxygen species (ROS) and reactive nitrogen species (RNS) and examples are: superoxide anion, hydroperoxyl radical, peroxyl radical, alkoxyl radical, hydroxyl radical, hydrogen peroxide, hypochlorite, hypochlorous acid, Ozone, Singlet oxygen and Nitric oxide, Nitrogen dioxide, peroxynitrite, peroxynitrous acid, dinitrogen trioxide, nitryl chloride, nitronium ion, alkylperoxynitrite, nitrosothiols respectively.
The latter protonates the former to generate nitronium ions which are the actual nitrating species.
The lower para-selectivity of HZSM-5 may be due to its hydrophobic pores that resist the diffusion of aqueous nitric acid resulting in fewer acidic sites available to generate required nitronium ions.
One could envisage a situation whereby exposure of a heterocyclic substrate to the highly acidic medium of the nitronium species could be minimized, with the nitrated product free to emerge from the flow reactor before it becomes polymerised.
2)]*) or heterolytic cleavage to form the nitronium cation (N[O.
A very early application of the use of superacids in inorganic chemistry was the demonstration that the nitronium ion is formed in a solution of nitric acid in sulfuric acid [4]