question_answer

The correct order of increasing basic nature of the following bases is

1.

2.

3.

4.

5.

A) \[2<5<1<3<4\]

B) \[5<2<1<3<4\]

C) \[2<5<1<4<3\]

D)        \[5<2<1<4<3\]

E)  \[2<5<4<3<1\]

Correct Answer: A

Solution :

\[OC{{H}_{3}}\]is strongest electron releasing group (+M effect) which opposes most the dispersion of lone pair of electron of nitrogen into the ring. Thus\[OC{{H}_{3}}\]being at para- position imparts highest basicity.\[N{{O}_{2}}\]being at meta- position stabilizes the electron pair of nitrogen only by\[-I\]effect. While N03 being present at para- position due to -M effect and \[-I\]effect stabilizes the lone pair of electron of nitrogen, most and impart least basicity.