The major product $\mathbf{H}$ of the given reaction sequence is \[ \mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{CO}-\mathrm{CH}_{3} \xrightarrow{{ }^{\ominus} \mathrm{CN}} \mathbf{G} \xrightarrow[\text { Heat }]{95 \% \mathrm{H}_{2} \mathrm{SO}_{4}} \mathbf{H} \]

JEE Advanced · 2012 · 08 Apr 2012 · Paper 2 · Aldehydes Ketones and Carboxylic Acids

The major product

H

of the given reaction sequence is

CH_{3} - CH_{2} - CO - CH_{3}^{⊖} CN G 95% H_{2} SO_{4} Heat H

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

Answer: (A)

Solution

The ketone reacts with CN⁻ to form a cyanohydrin (G). Upon heating with 95% H₂SO₄, the cyanohydrin undergoes dehydration and hydrolysis. The nitrile is hydrolyzed to a carboxylic acid, and the hydroxyl group is eliminated to form a double bond, giving 2-methylbut-2-enoic acid. The answer is (A).

JEE Advanced · 2012 · 08 Apr 2012 · Paper 2 · Single correct option

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

More JEE Advanced questions on Aldehydes Ketones and Carboxylic Acids

The sum of total number of carbonyl groups $(> C = O)$ present in the major products X and Y in the following reactions is ____.
JEE Advanced 2026View solution →
The major products obtained from the reactions in List-II are the reactants for the named reactions mentioned in List-I. Match each entry in List-I with the appropriate entry in List-II and choose the correct options.

List-I
(P) Stephen reaction
(Q) Sandmeyer reaction
(R) Hoffma …
JEE Advanced 2025View solution →
The correct reaction/reaction sequence that would produce a dicarboxylic acid as the major product is
JEE Advanced 2025View solution →
Reaction of iso-propylbenzene with $O_{2}$ followed by the treatment with $H_{3} O^{+}$ forms phenol and a by-product P. Reaction of P with 3 equivalents of $Cl_{2}$ gives compound Q. Treatment of Q with $Ca (OH)_{2}$ produces c …
JEE Advanced 2024View solution →
Complete reaction of acetaldehyde with excess formaldehyde, upon heating with conc. NaOH solution, gives P and Q. Compound P does not give Tollens' test, whereas Q on acidification gives positive Tollens' test. Treatment of P with excess cyclohexanone in the presence of catalytic …
JEE Advanced 2024View solution →
The option(s) with correct sequence of reagents for the conversion of $P$ to $Q$ is(are) :
JEE Advanced 2024View solution →