NITRATION OF BENZENE (Nitrobenzene [C₆H₅NO₂])

Similar to the alkylation and the chlorination of benzene, the nitration reaction is an electrophilic substitution of a benzene hydrogen (a proton) with a nitronium ion (NO₂⁺). The liquid-phase reaction occurs in presence of both concentrated nitric and sulfuric acids at approximately 50°C. Concentrated sulfuric acid has two functions: it reacts with nitric acid to form the nitronium ion, and it absorbs the water formed during the reaction, which shifts the equilibrium to the formation of nitrobenzene:

Most of the nitrobenzene (≈97%) produced is used to make aniline. Other uses include synthesis of quinoline, benzidine, and as a solvent for cellulose ethers.