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NEET levelSingle correct optionDifficulty 1 of 3g2060

Pyrrole is practically non-basic because

  1. Athe lone pair on nitrogen is part of the aromatic sextet and protonation on N would destroy aromaticity
  2. Bit has no nitrogen atom
  3. Cits nitrogen is sp hybridised and sterically hindered
  4. Dit contains a carbonyl group that withdraws the lone pair

Answer: A

Pyrrole needs the N lone pair to complete its six pi electrons (4 from the two C=C plus 2 from N). Using it for bonding to would break aromaticity, so pyrrole is an extremely weak base.
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