Question

Which extraction procedure will completely separate an amide from the by-product of the reaction between an amine and excess carboxylic acid anhydride?

A) Add 0.1M NaOH (aq) to quench unreacted anhydride. Then add diethyl ether and separate the layers. The amide can be obtained from the ether layer by evaporating the solvent.
B) Add 0.1 M HCl (aq) to quench unreacted anhydride. Then add diethyl ether and separate the layers. The amide can be obtained from ether layer by evaporating the solvent.
C) Add 0.1M NaOH (aq) to quench unreacted anhydride. Then add diethyl ether and separate the layers. The amide can be obtained from the aqueous layer by neutralizing with HCl (aq).
D) Add 0.1M HCl (aq) to quench the unreacted anhydride. Then add diethyl ether and separate the layers. The amide can be obtained from the aq. layer by neutralizing the NaOH (aq).

Answer 1

Option C, which involves adding 0.1M NaOH to quench unreacted anhydride, then adding diethyl ether and separating the layers, is the extraction procedure that will completely separate an amide from the by-product of the reaction between an amine and excess carboxylic acid anhydride.

Step-by-step explanation:

The extraction procedure that will completely separate an amide from the by-product of the reaction between an amine and excess carboxylic acid anhydride is option C. First, you would add 0.1M NaOH (aq) to quench unreacted anhydride. Then, you would add diethyl ether and separate the layers. The amide can be obtained from the aqueous layer by neutralizing with HCl (aq).