The major product of the following reaction is :
CH₃-CH(CH₃; |)-CH₂-CH₂-C(O; ∥)-Cl →((i) alcoholic NH₃; (ii) NaOH, Br₂) Major Product

Solution

Chemistry ma’am · 4 steps

Watch the carbon count: Hofmann bromamide throws away the C=O carbon, so a 6-carbon chain ends with 5.

1. Acid chloride to amide. Alcoholic NH₃ replaces Cl with NH₂. You get the amide (CH₃)₂CH-CH₂-CH₂-CONH₂, which still has all 6 carbons.
2. Hofmann bromamide. Br₂ with NaOH converts the amide into a primary amine with one carbon fewer. The C=O carbon leaves as carbonate, and the NH₂ ends up on the carbon that was next to it.

   (CH₃)₂CHCH₂CH₂CONH₂ →(Br₂, NaOH) (CH₃)₂CHCH₂CH₂NH₂

3. Amine to alcohol. NaNO₂ with HCl turns the primary aliphatic amine into an unstable diazonium salt. It loses N₂ at once, and water supplies OH in place of the NH₂.
4. So. The major product is the 5-carbon alcohol (CH₃)₂CH-CH₂-CH₂OH (3-methylbutan-1-ol), which is option (c).

The idea to keep. Hofmann bromamide always shortens the chain by one carbon. Then nitrous acid on a primary aliphatic amine gives the alcohol, because the diazonium ion breaks down at once.

Answer from the NTA final answer key. Solution by PrepWiser.