| Column 1 | Column 2 | Column 3 | | --- | --- | --- | | (I) Toluene | (i) $\mathrm{NaOH}/\mathrm{Br}_2$ | (P) Condensation | | (II) Acetophenone | (ii) $\mathrm{Br}_2/h\nu$ | (Q) Carboxylation | | (III) Benzaldehyde | (iii) $(\mathrm{CH}_3\mathrm{CO})_2\mathrm{O}/\mathrm{CH}_3\mathrm{COOK}$ | (R) Substitution | | (IV) Phenol | (iv) $\mathrm{NaOH}/\mathrm{CO}_2$ | (S) Haloform | Columns 1, 2 and 3 contain starting materials, reaction conditions, and type of reactions, respectively. The only CORRECT combination in which the reaction proceeds through radical mechanism is

JEE Advanced · 2017 · 21 May 2017 · Paper 1 · Hydrocarbons

Column 1	Column 2	Column 3
(I) Toluene	(i) $NaOH / Br_{2}$	(P) Condensation
(II) Acetophenone	(ii) $Br_{2} / h ν$	(Q) Carboxylation
(III) Benzaldehyde	(iii) $(CH_{3} CO)_{2} O / CH_{3} COOK$	(R) Substitution
(IV) Phenol	(iv) $NaOH / CO_{2}$	(S) Haloform

Columns 1, 2 and 3 contain starting materials, reaction conditions, and type of reactions, respectively.

The only CORRECT combination in which the reaction proceeds through radical mechanism is

(A)(III) (ii) (P)
(B)(IV) (i) (Q)
(C)(II) (iii) (R)
(D)(I) (ii) (R)✓ Correct

Answer: (D)

Solution

(I) Toluene with **(ii)

Br_{2} / h ν

** undergoes (R) free radical substitution at the benzylic position:

C_{6} H_{5} CH_{3} + Br_{2} h ν C_{6} H_{5} CH_{2} Br + HBr

The reaction proceeds through a radical mechanism initiated by light.

Answer: (D)

JEE Advanced · 2017 · 21 May 2017 · Paper 1 · Single correct option

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JEE Advanced · 2017 · 21 May 2017 · Paper 1 · Hydrocarbons

Solution

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