The reaction of $\mathbf{Q}$ with PhSNa yields an organic compound (major product) that gives positive Carius test on treatment with $\mathrm{Na}_{2}\mathrm{O}_{2}$ followed by addition of $\mathrm{BaCl}_{2}$. The correct option(s) for $\mathbf{Q}$ is (are).

(A) (see structure); (D) (see structure)

JEE Advanced · 2021 · 03 Oct 2021 · Paper 1 · Haloalkanes and Haloarenes

The reaction of

Q

with PhSNa yields an organic compound (major product) that gives positive Carius test on treatment with

Na_{2} O_{2}

followed by addition of

BaCl_{2}

. The correct option(s) for

Q

is (are).

(A)(see structure)
✓ Correct
(B)(see structure)
(C)(see structure)
(D)(see structure)
✓ Correct

Answer: (A), (D)

Solution

PhSNa (sodium thiophenoxide) acts as a nucleophile and undergoes nucleophilic aromatic substitution (SNAr) with activated aromatic halides. The reaction requires strong electron-withdrawing groups (like NO₂) to activate the ring.

The product must contain sulfur to give a positive Carius test (formation of BaSO₄ precipitate after oxidation with Na₂O₂).

Options (A) and (D) both have:

A nitro group (strong electron-withdrawing) to activate the ring
A good leaving group (F in A, Cl in D) at a position suitable for SNAr

The reaction replaces the halogen with -SPh group, and the resulting sulfur-containing compound gives a positive Carius test.

JEE Advanced · 2021 · 03 Oct 2021 · Paper 1 · One or more correct options

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JEE Advanced · 2021 · 03 Oct 2021 · Paper 1 · Haloalkanes and Haloarenes

Solution

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