Question

The major product of carbylamine reaction is :

• A. Carboxylic acid
• B. Aldehyde
• C. Cyanide
• D. Isocyanide

Hint:

Carbylamine test is given only by primary amines and produces foul-smelling isocyanides \((RNC)\). Remember: \[ RNH_2 + CHCl_3 + KOH \rightarrow RNC \]

Answer 1

The Correct Option is D

Step 1: Identify the Carbylamine reaction.
A primary amine reacts with chloroform $CHCl_3$ and alcoholic $KOH$ on heating. This reaction is the confirmatory test for primary amines.
Step 2: Determine the product.
\[ R-NH_2 + CHCl_3 + 3KOH \rightarrow R-N\equiv C + 3KCl + 3H_2O \] The product is an isocyanide $R-NC$ (also called carbylamine), which has a foul, nauseating smell. The carbon is bonded to nitrogen at its end ($R-N\equiv C$), unlike cyanide $R-C\equiv N$ where carbon is the terminal atom.
Step 3: Eliminate the distractors.
Carboxylic acids and aldehydes are not produced here. Cyanides ($R-CN$) and isocyanides ($R-NC$) are structural isomers; the Carbylamine reaction gives isocyanide, not cyanide.
\[ \boxed{\text{Isocyanide}} \]