Question

Arrange the following compound in an increasing order of basic strength in aqueous medium.
C6H5NH2, CH3NH2, (CH3)3N, (CH3)2NH​.

Answer 1

In this question, C6H5NH2 is least basic because of the -R effect of C6H5 group.

Now, (CH3)2NH is more basic than CH3NH2 because of the presence of +I effect of the two -CH3 groups.

CH3NH2 is more basic than (CH3)3N.

The above order is because of the solvation effect.

(CH3)2NH is more basic than (CH3)3N because of the stearic hindrance in the availability of electron in (CH3)3N.

Hence the increasing order of basic strength is

C6H5NH2 < (CH3)3N < CH3NH2 < (CH3)2NH