Predict the major product 'P' in the following sequence of reactions-

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Question

This question was previously asked in

NEET 2025 Official Paper (Held On: 04 May, 2025)

Answer 1

CONCEPT:

Free Radical Substitution and Nucleophilic Substitution

Step 1 (i) HBr and benzoyl peroxide: This is a free radical halogenation reaction. Benzoyl peroxide initiates the formation of free radicals, which then react with HBr to produce an alkyl bromide (methyl bromide in this case).
Step 2 (ii) KCN: The alkyl bromide formed in step 1 undergoes nucleophilic substitution by the cyanide ion (CN^-) to form a nitrile (CN) group attached to the carbon chain.
Step 3 (iii) Na(Hg)/C₂H₅OH: The nitrile group is reduced to a primary amine (-NH₂) by sodium amalgam in the presence of ethanol, completing the reaction pathway.

EXPLANATION:

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In the first step, free radicals generated by benzoyl peroxide lead to the formation of a methyl bromide intermediate from CH₃ (methyl group) and HBr.
In the second step, the cyanide ion (CN^-) attacks the methyl bromide, displacing the bromine atom and forming a nitrile group (-CN) on the carbon chain.
In the third step, sodium amalgam (Na(Hg)) in ethanol reduces the nitrile group (-CN) to a primary amine (-NH₂), resulting in the final product, a primary amine.

Therefore, the major product 'P' is Option 1.

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