JEE Main · 2021 · 20 Jul 2021 · Shift 1 · Compounds Containing Nitrogen

Compound

A

is converted to

B

on reaction with

CHCl_{3}

and KOH . The compound

B

is toxic and can be decomposed by C .

A, B

and C respectively are:

(A)Primary amine, nitrile compound, conc. HCl
(B)Primary amine, isonitrile compound, conc. HCl✓ Correct
(C)Secondary amine, isonitrile compound, conc NaOH
(D)Secondary amine, nitrile compound, conc. NaOH

Answer: (B)

Solution

Chloroform and KOH generate dichlorocarbene, which is attacked by the lone pair of an amine nitrogen; two successive eliminations of HCl then give the isocyanide:

RN H_{2} + CHC l_{3} + 3 KOH ⟶ RNC + 3 KCl + 3 H_{2} O

Both of those eliminations need a hydrogen on nitrogen, so only a primary amine responds, which is why the carbylamine test distinguishes it. The isocyanide formed is foul smelling and poisonous, and it is destroyed by acid hydrolysis, concentrated HCl returning the primary amine as its salt together with formic acid. So A is a primary amine, B is an isonitrile compound and C is concentrated HCl.

JEE Main · 2021 · 20 Jul 2021 · Shift 1 · Single correct option

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JEE Main · 2021 · 20 Jul 2021 · Shift 1 · Compounds Containing Nitrogen

Solution

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