Which of the following compounds gives positive carbylamine reaction ? a) (CH3)2NH b)… – Chemistry NEB 2082 (MCQs) Solution

The carbylamine reaction is a test for primary amines (both aliphatic and aromatic), where they react with chloroform and alcoholic KOH to form isocyanides (carbylamines), which have a foul odor.

R-NH₂+chloroformchloroform+KOH (alc)heatR-NC+H₂O+KCl

Carbylamine reaction: Primary amine + chloroform + alcoholic KOH → Isocyanide (foul-smelling)

Primary amines ( $RNH X_{2}$ ) give a positive carbylamine reaction.
Secondary amines ( $R X_{2} NH$ ) and tertiary amines ( $R X_{3} N$ ) do not give this reaction.

Analyzing the options:

a) $(CH X_{3}) X_{2} NH$ : Secondary amine → No reaction.
b) $(CH X_{3}) X_{3} N$ : Tertiary amine → No reaction.
c) $(CH X_{3}) X_{4} N X^{+}$ : Quaternary ammonium salt → No reaction.
d) $CH X_{3} NH X_{2}$ : Primary amine → Positive carbylamine reaction.

Thus, the correct answer is d) $CH X_{3} NH X_{2}$ .

Which of the following compounds gives positive carbylamine reaction ? a) (CH3)2NH b) (CH3)3N c) (CH3)4N+ d) CH3NH2

Discussion

More Chemistry questions