Amino Group Detection ($$1^\circ$$ Amine)

Formula / Core Reaction:

$$\text{R-NH}_2 + \text{CHCl}_3 + 3\text{KOH} (\text{alc.}) \xrightarrow{\Delta} \text{R-NC} + 3\text{KCl} + 3\text{H}_2\text{O}$$

Concept: Primary aliphatic or aromatic amines react with chloroform and alcoholic potassium hydroxide (Carbylamine reaction) to synthesize an offensive-smelling isocyanide (carbylamine).

Notation / Key Observation:

• $$\text{R-NC}$$: Alkyl/Aryl Isocyanide (Foul/Extremely unpleasant odor);
• Note: Test is exclusive to $$1^\circ$$ amines ($$2^\circ$$ and $$3^\circ$$ amines do not show this reaction).