Question

Identify product B obtained in the following reaction:
\[ \text{CH}_3-\text{CH}_3 \;\xrightarrow[\Delta]{\text{HNO}_2}\; A \;\xrightarrow[\text{ether}]{\text{LiAlH}_4}\; B \]

• A. Ethanoic acid
• B. Ethanal
• C. Ethanol
• D. Ethanamine

Hint:

\(\text{LiAlH}_4\) is commonly used to reduce nitro and nitrile compounds into amines.

Answer 1

The Correct Option is D

Step 1: Understand the first reaction.
When ethane reacts with nitrous acid (\(\text{HNO}_2\)) on heating, it undergoes substitution to form nitroethane, which further rearranges to give ethyl nitrite that finally forms ethanamine precursor (nitroso derivative).
Step 2: Identify intermediate A.
The reaction of alkane with nitrous acid leads to formation of a nitro/nitroso compound that can be reduced to an amine. Thus, compound \(A\) is an intermediate nitrogen-containing compound.
Step 3: Effect of \(\text{LiAlH}_4\).
Lithium aluminium hydride is a strong reducing agent that converts nitro or nitroso compounds into primary amines.
Step 4: Final product identification.
After reduction, the final product formed is ethanamine (\(\text{CH}_3\text{CH}_2\text{NH}_2\)).