Identify the compound produced by the reduction of Ethanenitrile with Lithium aluminium hydride :
Show Hint
- Ethylamine
- Ethanal
- Propylamine
- Methylamine
The Correct Option is A
Solution and Explanation
The compound is Ethanenitrile. In IUPAC nomenclature, "ethane" indicates a 2-carbon chain. The structure is: \(\text{CH}_3-\text{C}\equiv\text{N}\).
Step 2: Writing the reduction reaction.
When \(\text{CH}_3\text{CN}\) reacts with \(\text{LiAlH}_4\), four hydrogen atoms are added across the triple bond: \[ \text{CH}_3-\text{C}\equiv\text{N} + 4[\text{H}] \xrightarrow{\text{LiAlH}_4} \text{CH}_3-\text{CH}_2-\text{NH}_2 \]
Step 3: Naming the product.
The product formed is \(\text{CH}_3\text{CH}_2\text{NH}_2\). This consists of an ethyl group attached to an amino group, which is Ethylamine (or Ethanamine).
Step 4: Verification of carbon count.
The starting material has 2 carbons (Ethanenitrile). The reduction of nitriles preserves the carbon count.
• Methylamine has 1 carbon (Incorrect).
• Propylamine has 3 carbons (Incorrect).
• Ethylamine has 2 carbons (Correct).
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(ii) Ethylamine is soluble in water whereas aniline is not.
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(iv) Although amino group is o– and p– directing in aromatic electrophilic substitution reactions, aniline on nitration gives a substantial amount of m-nitroaniline.
(v) Aniline does not undergo Friedel-Crafts reaction.
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