Hofmann Bromamide Reaction and Nitration of Aniline
Given below are two statements :
Statement I : Heating benzamide with bromine in an ethanolic solution of sodium hydroxide will give benzylamine.
Statement II : Nitration of aniline with at produces -nitroaniline in higher amount than -nitroaniline (pH adjusted).
In the light of the above statements, choose the correct answer from the options given below :
Options
Both Statement I and Statement II are true
Both Statement I and Statement II are false
Statement I is true but Statement II is false
Statement I is false but Statement II is true
Topics & Concepts
Step-by-Step Solution
To determine the correctness of Statements I and II, let us analyze them individually:
Analysis of Statement I: When benzamide () is treated with bromine in the presence of an aqueous or ethanolic solution of sodium hydroxide (), it undergoes the Hofmann bromamide degradation reaction. In this reaction, the carbonyl group is removed as carbonate, yielding a primary amine containing one carbon atom fewer than the starting amide:
The primary product formed is aniline (), and not benzylamine (). Therefore, Statement I is false.
Analysis of Statement II: Direct nitration of aniline using a mixture of concentrated and at leads to protonation of aniline in the strongly acidic medium, forming the anilinium ion ().
Since the anilinium ion is a strong -directing group, a substantial amount of -nitroaniline is formed alongside - and - isomers. The percentage yield of the products obtained is:
- -nitroaniline:
- -nitroaniline:
- -nitroaniline:
Since , -nitroaniline is formed in a significantly higher amount than -nitroaniline. Therefore, Statement II is true.
Conclusion:
- Statement I is false, but Statement II is true.
Thus, the correct choice is Option D.