MolSynapsequestion bank
MolSynapse / Question bank / General Organic Chemistry I: Electronic Effects / Aromatic, antiaromatic and non-aromatic rings
JEE Main levelSingle correct optionDifficulty 2 of 3g1240

If the ring of the anion shown were planar, it would have

  1. A6 pi electrons and be aromatic
  2. B8 pi electrons and be aromatic
  3. C10 pi electrons and be aromatic
  4. D8 pi electrons and be antiaromatic

Answer: D

The ion shown is the cycloheptatrienyl anion. It has three C=C bonds (6 pi electrons) plus the lone pair in a p orbital (2), so 8 pi electrons (4n, n = 2). A planar ring would therefore be antiaromatic.
Practice General Organic Chemistry I: Electronic Effects More on Aromatic, antiaromatic and non-aromatic rings
Previous questionNext question

More questions on Aromatic, antiaromatic and non-aromatic rings