Nitrating Mixture

Nitrating Mixture 

a mixture of concentrated nitric acid or nitrogen oxides with inorganic compounds (H₂SO₄, BF₃, and AlCl₃) or organic compounds (for example, acetic anhydride). It generates the active nitrating species NO₂⁺ (the nitronium cation):

2H₂SO₄ + HNO₃ → NO₂⁺ + H₃O⁺ + 2HSO₄^-

Nitrating mixtures are used to nitrate aromatic compounds (mainly a mixture of nitric and sulfuric acids) and unsaturated aliphatic compounds, as well as in the production of nitroamino compounds (nitramines) and nitro esters.