Question

Choose the correct option regarding $S_{n}Ar$ i.e. Nucleophilic Aromatic Substitution reaciton:
Here
EWG- Electron withdrawing group
EDG- Electron donating group

• A. More the number of EWG at ortho and para position to the halogen atom,faster is the reaction.
• B. Less the number of EWG at ortho and para position to the halogen atom,faster is the reaction.
• C. More the number of EDG at ortho and para position to the halogen atom,faster is the reaction.
• D. None of the above

Answer 1

The correct option is A More the number of EWG at ortho and para position to the halogen atom,faster is the reaction.

Effect of EWG on $S_{n}Ar$ i.e. Nucleophilic Aromatic Substitution reaciton:
More the number of EWG at ortho and para position to the halogen atom,faster is the reaction.
Example:
o-Nitrochlorobenzene requires the highest temperature (p-Nitrochlorobenzene reacts at same temperature as well).
whereas 2,4,6-Trinitrochlorobenzene requires the lowest temperature.