The major product of the following reaction is: (i) $\mathrm{NaNO}_{2} / \mathrm{H}^{+}$ (ii) $\mathrm{CrO}_{3} / \mathrm{H}^{+}$ (iii) $\mathrm{H}_{2} \mathrm{SO}_{4}$ (conc.), $\Delta$

JEE Main · 2019 · 12 Jan 2019 · Shift 2 · Compounds Containing Nitrogen

The major product of the following reaction is:

(i)

NaNO_{2} / H^{+}

(ii)

CrO_{3} / H^{+}

(iii)

H_{2} SO_{4}

(conc.),

Δ

Answer: (A)

Treatment with

NaNO X_{2} / H X^{+}

turns the aromatic amine into a diazonium salt;

CrO X_{3} / H X^{+}

then oxidises the side chain to a carboxylic acid while the diazonium group is hydrolysed to a phenolic

- OH

. Finally hot concentrated

H X_{2} SO X_{4}

drives an intramolecular Friedel

-

Crafts acylation, the carboxyl closing onto the ring ortho to the

- OH

to build a six-membered cyclic ketone. The product is the hydroxy-substituted tetralone.

JEE Main · 2019 · 12 Jan 2019 · Shift 2 · Single correct option