JEE Advanced2026ChemistryAminesActual
In the following reaction sequence, P , Q , S and T are the major products. The correct statement(s) about P , Q , S and T is(are)
Options
- AQ on treatment with ethanol generates an aromatic aldehyde.
- BS gives positive phthalein dye test.
- CP is a dinitro compound.
- DT is a coloured compound.
Correct answer
B. S gives positive phthalein dye test.
Step-by-step solution
In the first reaction sequence: Aniline reacts with acetic anhydride in the presence of pyridine to undergo acetylation, forming acetanilide. Acetanilide is treated with a nitrating mixture (conc. HNO ₃ and conc. H ₂ SO ₄ ) at 288 K . The - NHCOCH ₃ group is moderately activating and ortho/para directing. Due to steric hindrance, the major product P is p -nitroacetanilide. P is hydrolyzed with H ₃ O ^+ to yield p -nitroaniline. p -nitroaniline is diazotized using NaNO ₂/ HCl at 273-278 K to form the diazonium salt