Question

Aldol condensation is shown by compounds containing:

• A. Only carbonyl group
• B. \(\alpha\)-hydrogen and carbonyl group
• C. Triple bond
• D. Ether linkage

Hint:

Formaldehyde and benzaldehyde do not undergo aldol condensation because they do not contain \(\alpha\)-hydrogen atoms.

Answer 1

The Correct Option is B

Concept: Aldol condensation is shown by aldehydes or ketones that contain at least one \(\alpha\)-hydrogen atom.

Step 1: Understanding the requirement of aldol condensation.
In aldol condensation, one molecule forms an enolate ion using an \(\alpha\)-hydrogen atom. This enolate ion attacks another molecule containing a carbonyl group.

Step 2: Necessary conditions for the reaction.
The compound must contain: \[ \text{(i) A carbonyl group} \] and \[ \text{(ii) At least one }\alpha\text{-hydrogen} \] Without \(\alpha\)-hydrogen, enolate ion formation cannot occur.

Step 3: Example of aldol condensation.
Acetaldehyde undergoes aldol condensation: \[ 2CH_3CHO \rightarrow CH_3CH(OH)CH_2CHO \] Thus, compounds containing both carbonyl group and \(\alpha\)-hydrogen undergo aldol condensation. Therefore, the correct answer is: \[ \boxed{\text{\(\alpha\)-hydrogen and carbonyl group}} \]