The electrophile, `E^(o+)` attacks the benzene ring to generate the intermediate `sigma`-complex. Of the following, which `sigma`-complex is of lowest energy ?

Options

A.
B.
C.
D.

Answer

C

Explanation

Since - `NO_2` group is a powerful electron-withdrawing group, therefore, carbocations (a) , (b), (d) are destabilized. However, in carbocation (c ) there is no - `NO_2` group. Thus, `alpha`-complex (c ) is of lowest energy .