Question

Question #66ea0

Answer 1

using electrophilic aromatic substitution.

Explanation:

Suppose a group G is attached on benzene, and an electrophile is ready to attach itself.

case-1: G is electron releasing group
in the different canonical forms you draw, it can be seen that the positive charge is more stable if electrophile tends to attach at 'o' /'p', but not at 'm'.

case-1: G is electron withdrawing group
in the different canonical forms you draw, it can be seen that the positive charge is more stable if electrophile tends to attach at 'm' than at 'o'/'p'.

SO IT CAN BE CONCLUDED THAT IF 'G' IS ELECTRON RELEASING THAN BENZENE IS 'ORTHO' AND 'PARA' DIRECTING, BUT IF 'G' IS WITHDRAWING THAN 'META' DIRECTING.