Question

What is the action of the following reagent on chlorobenzene?

Conc. HNO₃

Answer 1

Chlorobenzene undergoes nitration with concentrated nitric acid (usually in the presence of conc. H₂SO₄) to form a mixture of ortho-nitrochlorobenzene and para-nitrochlorobenzene.

Chlorine is an ortho and para-directing group, so substitution occurs at o- and p-positions.

\[\ce{C6H5Cl + HNO3 ->[conc. H2SO4] \underset{Ortho nitrochlorobenzene}{ClC6H4NO2} + \underset{Para nitrochlorobenzene}{ClC6H4NO2} + H2O}\]