Question

Which of the following compounds is obtained when \( \mathrm{C_2H_5NH_2} \) is treated with excess \( (\mathrm{CH_3CO})_2\mathrm{O} \) in presence of pyridine?

• A. \( \mathrm{C_2H_5N(COCH_3)_2} \)
• B. \( (\mathrm{C_2H_5})_2\mathrm{NH} \)
• C. \( \mathrm{C_2H_5COOH} \)
• D. \( \mathrm{C_2H_5NHCOCH_3} \)

Hint:

Excess acylating agent leads to complete acylation of amines.

Answer 1

The Correct Option is A

Step 1: Nature of ethylamine.
Ethylamine is a primary amine and contains an active hydrogen atom attached to nitrogen.

Step 2: Reaction with excess acetic anhydride.
When treated with excess acetic anhydride in presence of pyridine, both hydrogen atoms of the amine group are replaced by acetyl groups.

Step 3: Formation of diacetyl derivative.
This leads to the formation of N,N-diacetyl ethylamine.

Step 4: Conclusion.
Hence, the product formed is \( \mathrm{C_2H_5N(COCH_3)_2} \).