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Haloalkanes and Haloarenes — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryHaloalkanes and Haloarenes1 Mark
MCQ
Which of these is $o, p-$directing and deactivating group?
  • A
    $−F$
  • B
    $−Cl$
  • C
    $−Br$
  • ✓
    All of these
✓

Answer

Correct option: D.
All of these
$X− ($halogen group$)$ has two effects $−I \ \&\ +M.$
Due to the $−I$ group, it reduces the electron density of benzene so halobenzene is less reactive than benzene for electrophilic substitution reaction.
But due to the $+M$ effect, it is ortho, para directing $($resonance effect predominates over inductive effect$)$ and in halobenzene, further substitution takes place at ortho and para positions.

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