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
Nitriles (alkyl cyanides) undergo strong reduction when treated with Lithium aluminium hydride ($LiAlH_4$).
Step 2: Meaning
This severe reduction converts the carbon-nitrogen triple bond ($-C \equiv N$) completely into a primary amine group ($-CH_2-NH_2$).
Step 3: Analysis
The starting material is Ethanenitrile, which has the formula $CH_3-C \equiv N$.
It contains exactly two carbon atoms. Reduction by $LiAlH_4$ adds two hydrogen atoms to the carbon and two to the nitrogen, maintaining the two-carbon chain.
Reaction: $CH_3-C \equiv N \xrightarrow{LiAlH_4} CH_3-CH_2-NH_2$.
The IUPAC name of the product is Ethanamine, and its common name is Ethylamine.
Step 4: Conclusion
The resulting two-carbon amine matches option (A).
Final Answer: (A)
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