Question

a) Carbylamines have an offensive smell.

i) Write the carbylamine reaction.

ii) How will you convert aniline into phenol?

b) How will you convert an amide into the following? An amine with one carbon atom less than that of the amide.

i) An amine containing the same number of carbon atoms as that in the amide.

Answer 1

a) i) Aliphatic and aromatic primary amines on heating with chloroform and ethanolic potas skim hydroxide form foul smelling substances called isocyanides or carbylamines. This reaction is known as carbylamine reaction or isocyanide test and is used as a test for primary amines.

ii) Aniline on diazotisation gives benzene diazonium chloride. This on warming with water gives phenol.

b) i) By Hoffman bromamide degradation reaction- when an amide is treated with bromine in an aqueous or ethanolic solution of sodium hy-droxide at about 343 K, an amine with one carbon less than that present in the amide is formed.

ii) By reduction – An amide on reduction with LiAIH₄ or Na and ethanol an amine having the same number of carbon atoms as that in the amide is formed.