Question

Nitration of bromobenzene gives two bromo one nitro benzene and 4 bromo one nitro benzene but when bromination of nitro benzene is done then it gives three bromo one nitrobenzene why

Answer 1

Bromo benzene is ortho and para directing for electrophilic addition reaction because it shows resonance over benzene ring which increases the electron density on ortho and para position of the benzene ring but nitrobenzene is meta directing for electrophilic addition reaction because it shows -I effect i.e electron withdrawing group which decreases the electron density on ortho and para position so it shows meta addition for electrophilic addition reaction.
Thats why bromobenzene on nitration gives 2 bromo 1 nitro benzene and 4 bromo 1 nitro benzene and nitro benzene on bromination gives 3 bromo 1 nitrobenzene.
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