Anisole nitration during gamma-irradiation of aqueous nitrite and nitrate solutions: free radical versus ionic mechanisms

作者：Elias Gracy; Mincher Bruce J^*; Mezyk Stephen P; Cullen Thomas D; Martin Leigh R

来源：Environmental Chemistry, 2010, 7(2): 183-189.

DOI：10.1071/EN09109

• N-centred radicals
• nitronium ion
• nitrosonium ion
• radical chemistry

In the irradiated, acidic condensed phase, radiation-enhanced nitrous acid-catalysed, nitrosonium ion, electrophilic aromatic substitution followed by oxidation reactions dominated over radical addition reactions for anisole. This ionic mechanism would predominate in urban atmospheric aerosols and nuclear fuel dissolutions. Irradiated neutral nitrate anisole solutions were dominated by mixed nitrosonium/nitronium ion electrophilic aromatic substitution reactions, but with lower product yields. Solutions such as these might be encountered in water treatment by e-beam irradiation. Irradiation of neutral nitrite anisole solutions resulted in a statistical substitution pattern for nitroanisole products, suggesting non-electrophilic free radical reactions involving the (center dot)NO(2) radical. Although often proposed as an atmospheric nitrating agent, (center dot)NO(2) radical is unlikely to have an important effect in the acidic condensed phase in the presence of more reactive, competing species such as nitrous acid.

• 出版日期2010