Question

Arrange the following compounds in the ascending order of their basic strength and give reasons for your answer:

Methylamine, Aniline, Ethylamine, Diethyl ether

Answer 1

Compounds in ascending order of their basic strength:

diethyl ether < Aniline < Methylamine < ethylamine

In aliphatic amines, due to the presence of electron donating alkyl group, electron density on nitrogen increases. Hence lone pair is easily available for protonation.

In aniline, the lone pair of nitrogen is in conjugation with benzene and less available for protonation hence aniline is less basic than aliphatic amine and others are inert in nature due to stable C-O-C bond