Question

Which of the following is ortho/para directing and deactivating group?

• A. $-F$
• B. $-Cl$
• C. $-Br$
• D. All of the above

Answer 1

The correct option is D All of the above

Halogen group (-X) has two effects
(i) Negative inductive effect (-I)
(ii) Positive resonance effect (+R)

Due to -I effect, it attracts the electron towards itself and reduces the electron density on benzene so it deactivates the ring.

Due to +R effect, it increases the electron density at ortho and para positions by delocalisation of electrons.

Hence, in halobenzene substitution takes place at ortho and para positions.