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JEE Advanced levelSingle correct optionDifficulty 3 of 3o2153

The meta product dominates in the nitration of nitrobenzene mainly because

  1. Anitronium ion is repelled only by the ortho and para carbons because they carry partial negative charge
  2. Bmeta attack gives an arenium ion with positive charge on the nitrogen of the nitro group
  3. Cthe nitro group donates electrons to the meta position by +M effect
  4. Dortho and para attack each give an arenium ion contributor with positive charge on the carbon bearing the electron-withdrawing nitro group

Answer: D

In ortho and para attack, one resonance form places the positive charge on the ring carbon directly bonded to the nitro group, a very unfavourable adjacent positive-charge arrangement. In meta attack the charge is never placed there, so that pathway is least destabilised. The nitro group withdraws electrons by -I and -M effects at all positions, and the ortho and para carbons are the most electron-poor.
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