Practicing Success

Target Exam

CUET

Subject

Chemistry

Chapter

Organic: Amines

Question:

Case: Read the following passage and answer accordingly

Amines are prepared mainly by the reduction of nitro compounds. Alkyl or benzyl halide on reaction with an ethanolic solution of ammonia undergoes nucleophilic substitution reaction in which the halogen atom is replaced by an amino group. Amines are prepared from Phthalimide. Treating an amide with bromine in an aqueous or ethanolic solution of sodium hydroxide result in amines.

Which is the most convenient method to prepare primary amine-containing one carbon atom less?
Options:
Gabriel phthalmidie synthesis
Reductive amination of aldehydes
Hofmann bromamide reaction
All of these
Correct Answer:
Hofmann bromamide reaction
Explanation:
Hoffmann developed a method for the preparation of primary amines by treating an amide with bromine in an aqueous or ethanolic solution of sodium hydroxide. In this degradation reaction, migration of an alkyl or aryl group takes place from the carbonyl carbon of the amide to the nitrogen atom. The amine so formed contains one carbon less than that present in the amide.