The desired product X can be prepared by reacting the major product of the reactions in LIST-I with one or more appropriate reagents in LIST-II. (Given, order of migratory aptitude: aryl > alkyl > hydrogen) | LIST-I | LIST-II | |--------|--------| | P. (see structure) | 1. $\mathrm{I}_{2}$, NaOH | | Q. (see structure) | 2. $\left[\mathrm{Ag}(\mathrm{NH}_{3})_{2}\right]\mathrm{OH}$ | | R. (see structure) | 3. Fehling solution | | S. (see structure) | 4. HCHO, NaOH | | | 5. NaOBr | The correct option is

(D) $\mathbf{P} \rightarrow 1,5; \mathbf{Q} \rightarrow 2,3; \mathbf{R} \rightarrow 1,5; \mathbf{S} \rightarrow 2,3$

(A) $\mathbf{P} \rightarrow 1; \mathbf{Q} \rightarrow 2,3; \mathbf{R} \rightarrow 1,4; \mathbf{S} \rightarrow 2,4$

(B) $\mathbf{P} \rightarrow 1,5; \mathbf{Q} \rightarrow 3,4; \mathbf{R} \rightarrow 4,5; \mathbf{S} \rightarrow 3$

(C) $\mathbf{P} \rightarrow 1,5; \mathbf{Q} \rightarrow 3,4; \mathbf{R} \rightarrow 5; \mathbf{S} \rightarrow 2,4$

JEE Advanced · 2018 · 20 May 2018 · Paper 2 · Aldehydes Ketones and Carboxylic Acids

The desired product X can be prepared by reacting the major product of the reactions in LIST-I with one or more appropriate reagents in LIST-II.

(Given, order of migratory aptitude: aryl > alkyl > hydrogen)

LIST-I	LIST-II
P. (see structure)	1. $I_{2}$ , NaOH
Q. (see structure)	2. $[Ag (NH_{3})_{2}] OH$
R. (see structure)	3. Fehling solution
S. (see structure)	4. HCHO, NaOH
	5. NaOBr

The correct option is

(A) $P \to 1; Q \to 2, 3; R \to 1, 4; S \to 2, 4$
(B) $P \to 1, 5; Q \to 3, 4; R \to 4, 5; S \to 3$
(C) $P \to 1, 5; Q \to 3, 4; R \to 5; S \to 2, 4$
(D) $P \to 1, 5; Q \to 2, 3; R \to 1, 5; S \to 2, 3$ ✓ Correct

Answer: (D)

Solution

The target product X is diphenylacetic acid. Analyzing each starting material in LIST-I and the reagents needed: (P) undergoes pinacol-pinacolone rearrangement followed by haloform reaction (1) or Hofmann rearrangement (5) to give X. (Q) is an aldehyde that undergoes oxidation with Tollens' reagent (2) or Fehling solution (3) to give X. (R) undergoes Cannizzaro reaction or oxidation to give X. (S) is a ketone that undergoes oxidation. The correct matching is P→1,5; Q→2,3; R→1,5; S→2,3.

JEE Advanced · 2018 · 20 May 2018 · Paper 2 · Single correct option

Practise more: all JEE Advanced PYQs on Aldehydes Ketones and Carboxylic Acids →

JEE Advanced · 2018 · 20 May 2018 · Paper 2 · Aldehydes Ketones and Carboxylic Acids

Solution

More JEE Advanced questions on Aldehydes Ketones and Carboxylic Acids