A procedure for quantitative regioselective nitration of aromatic hydrocarbons in the laboratory

Aromatic hydrocarbons are nitrated by metallic nitrates impregnated on the K10 montmorillonite in the presence of acetic anhydride (Menke conditions). The influence on this stoichiometric reaction of the conditions (metallic cation; solvent; temperature) is studied. With toluene as the test molecule, the reaction is optimized to a 100% yield combined with a 8:1 para preference (79% para, 20% ortho, 1% meta).