Question

Write short notes on the following:

1. Carbylamine reaction.

2. Hoffman’s bromamide reaction.

Answer 1

1. Methyl amine is a 1° amine and so it gives the carbylamine test. When methylamine is warmed with chloroform and alcoholic solution of KOH, foul smelling methyl isocyanide is formed.

Dimethyl amine is a 2° amine and hence it does not answer carbylamine test. Or they can be distinguished by Hinsberg’stest.

2. When an acid amide is heated with Br and an aqueous or ethanolic solution of alkali, a primary amine containing one carbon less than the initial amide is obtained. This is called Homann’s bromamide degradation reaction.