Consider the following reaction sequence: Toluene Conc. HNO ₃ + Conc. H ₂ SO ₄ Major Product (A) (A) Br ₂ /Fe (B) (B) 1. Sn/HCl; 2. NaNO ₂ /HCl (0-5 ^ C); 3. H ₃ PO ₂ /H ₂ O (C) (C) KMnO ₄ , H ^+ , (D) The structure of the final product (D) is:

Step-by-step solution

The reaction sequence proceeds as follows: 1. Nitration: Toluene undergoes electrophilic aromatic substitution with concentrated HNO ₃ and H ₂ SO ₄ . The methyl group is ortho/para-directing, and due to steric hindrance, the major product (A) is 4-nitrotoluene (p-nitrotoluene). 2. Bromination: 4-nitrotoluene reacts with Br ₂ /Fe . The - CH ₃ group is activating and ortho/para-directing, while the - NO ₂ group is deactivating and meta-directing. Both direct the incoming bromine electrophile to the position ortho to