Question

Carbylamine test is performed in alcoholic $KOH$ by heating a mixture of:

• A. Chloroform and silver powder
• B. Trihalogenated methane and a primary amine
• C. An alkyl halide and a primary amine
• D. An alkyl cyanide and a primary amine

Answer 1

Answer: (B)

Carbylamine test is given by $1^{\circ }$ amine with $CHC{l}_3+KOH$
$RN{H}_2+CHC{l}_3+KOH\to \underset{\text{Isocyanide}}{R\stackrel{\oplus }{N}\equiv \stackrel{\ominus }{C}}$
It gives an offensive smell of isocyanide
Mechanism proceeds via carbene
$\left(:CC{l}_2\right)$ or $\left(:C{X}_2\right)$ or $\left(:CX{X}^1\right)$
$(X{X}^1\Rightarrow$ Two different halogens)