Question

A. Phenyl methanamine
B. N,N-Dimethylaniline
C. N-Methyl aniline
D. Benzenamine

Choose the correct order of basic nature of the above amines.

• A. $A>B>C>D$
• B. $A>C>B>D$
• C. $D>B>C>A$
• D. $D>C<B>A$

Answer 1

The correct option is A $A>B>C>D$

In B,C,D the lone pairs of nitrogen are involved in resonance with the ring, where as it is not the case in compound A
So, tendency to donate the lone pair is the highest in A . So, A is most basic.
In B, there are two methyl groups attached to nitrogen which show $+I$ effect.
In C, there is one methyl group attached to nitrogen which show $+I$ effect.
In D, there is no methyl group attached to nitrogen.
Higher the number of electron donating group (methyl groups) attached to nitrogen,more is the availability of nitrogen's lone pair and more is the basicity.
So, B is more basic than C and D is the least basic
Correct order is
$A>B>C>D$