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JEE Main 2025 Apr 7 Shift 2, Chemistry Q7: Properties of Alkyl Halides (Halo Alkanes) & Aryl Halides (Halo Arenes)

JEE Main2025Apr 7, Shift 2Chemistry
Q.

Match List-I with List-II

List-I
Conversion		List-II
Reagents, Conditions used
(A) (I) Warm, HO
(B) (II) (a) NaOH, 368 K ; (b) HO
(C) (III) (a) NaOH, 443 K; (b) HO
(D) (IV) (a) NaOH, 623 K, 300 atm ; (b) HO

Choose the correct answer from the options given below :

  1. A

    (A)-(II), (B)-(III), (C)-(I), (D)-(IV)

  2. B

    (A)-(III), (B)-(IV), (C)-(II), (D)-(I)

  3. C

    (A)-(IV), (B)-(III), (C)-(II), (D)-(I)

  4. D

    (A)-(IV), (B)-(III), (C)-(I), (D)-(II)

Solution

Aryl halides undergo nucleophilic aromatic substitution only when the ring is activated by strongly electron-withdrawing groups such as at the ortho/para positions, since these groups stabilise the negatively charged intermediate through resonance.

Simple chlorobenzene, with no activating group, has an extremely unreactive ring; hydrolysing it to phenol requires the harshest conditions: NaOH at very high temperature and pressure (623 K, 300 atm), corresponding to (IV).

Adding one ortho group provides activation, allowing hydrolysis at a lower temperature of 443 K, corresponding to (III).

With two groups the ring is activated further, so a milder condition of 368 K suffices, corresponding to (II).

With three groups (picryl chloride), the ring is so strongly activated that simple warming with water hydrolyses the C-Cl bond, corresponding to (I).

(A)-(IV), (B)-(III), (C)-(II), (D)-(I).

Concept behind this question

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