Q6 · CSIR NET Chemistry, June 2013
Paper: CSIR NET June 2013 · Subject: Organic Chemistry · Chapter: General Organic Chemistry · Topic: General Organic Chemistry – General · Marks: 2 · Difficulty: Medium
Among the following compounds, the one which has highest dipole moment is
(a)

(b)

(c)

(d)

Answer
Answer: B ✓ checked by 4AB · confidence high
Explanation
Sesquifulvalene (b) can polarise into a cyclopentadienide anion and a tropylium cation, both aromatic, so it has by far the largest dipole. (a) fulvalene gains nothing on polarisation, (c) would need an antiaromatic 8π seven-membered anion, and (d) is a simple fulvene.
Study loop for General Organic Chemistry