Why in strongly acidic medium aniline become less reactive towards electrophilic reagent

this happens due to protonation of NH₂ group & thus anilium ion gets +ve charge ,

this group becomes highly -R & -I electron withdrawing group hence it resists the attack

of electrophlile at ortho or para position , therefore electrophile attacks at meta position  (electron rich site)...

this group is de activates the ring towards electrophile attack  & hence less reactive towards

electrophilic substitution reaction ....

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