Nitrtaatio

Nitrtaatio, commonly referred to in English as nitration, is the chemical introduction of one or more nitro groups (-NO2) into an organic substrate. It is a central transformation in aromatic chemistry and is used to prepare a wide range of nitro compounds that serve as intermediates for dyes, pharmaceuticals, agrochemicals, and energetic materials. The term can also apply to nitration of some aliphatic substrates, though the aromatic case is by far the most studied and widely employed.

For aromatic nitration, the key electrophilic species is the nitronium ion (NO2+). This active oxidizing agent is generated in situ from nitric acid in the presence of a strong acid such as sulfuric acid. The reaction proceeds via an arenium ion intermediate and is influenced by existing substituents, which direct the nitro group to ortho, meta, or para positions relative to activating or deactivating groups. Controlling reaction conditions is important to favor monosubstitution and to minimize over-nitration or side reactions. The process is highly exothermic and requires careful temperature and acid-concentration management.

Common nitrating systems involve mixtures of concentrated sulfuric and nitric acids, though alternative reagents such as nitronium salts are used in some settings, including modern or flow-chemistry methods. The scope includes benzene, substituted benzenes, anisoles, and heteroaromatic rings; reactivity and selectivity vary with substituents and ring electronics. Safety and environmental considerations are essential due to the corrosive, exothermic nature of the reagents and the production of hazardous wastes.