JEE Advanced · 2012 · 08 Apr 2012 · Paper 1 · Aldehydes Ketones and Carboxylic Acids

The number of aldol reaction(s) that occurs in the given transformation is

(A)1
(B)2
(C)3✓ Correct
(D)4

Answer: (C)

Solution

The transformation shown involves multiple aldol condensations. An aldol reaction occurs when an enolate ion (formed from a carbonyl compound with α-hydrogens) attacks another carbonyl group. Examining the given transformation, the product is formed through three sequential aldol reactions: the first aldol forms a β-hydroxy carbonyl, the second extends the chain further, and the third completes the cyclic structure. Therefore, 3 aldol reactions occur in this transformation.

JEE Advanced · 2012 · 08 Apr 2012 · Paper 1 · Single correct option

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