Consider the following reaction sequence starting from p -toluidine: p -Toluidine (i) Ac ₂ O / Pyridine (ii) Conc. HNO ₃ / Conc. H ₂ SO ₄ (iii) H ₃ O ^+, (iv) NaNO ₂ / HCl, 273-278 K (v) H ₃ PO ₂ , H ₂ O Major Product The final major product formed in the above reaction sequence is:

Step-by-step solution

p -toluidine reacts with acetic anhydride to form p -acetotoluidide, protecting the amino group. Nitration of p -acetotoluidide with conc. HNO ₃ and conc. H ₂ SO ₄ occurs at the position ortho to the strongly activating - NHAc group, yielding 3-nitro-4-acetaminotoluene. Hydrolysis with H ₃ O ^+ removes the acetyl group, giving 3-nitro-4-aminotoluene. Treatment with NaNO ₂ and HCl at 273-278 K converts the amino group into a diazonium salt (3-nitro-4-methylbenzenediazonium chloride). Finally, reduction with H ₃ PO ₂