UPSC Combined Geo-Scientist, Mains · 2017 · Mains Paper III
Q6(g). SN1 and aromatic cations
Question
Compare SN1 behaviour of 5-bromocyclopenta-1,3-diene (I) and 7-bromocyclohepta-1,3,5-triene (II).
Answer in brief
II undergoes ionisation much more readily because it forms the aromatic tropylium ion.
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CoversSN1aromatic cationsSubstitution reactions
All parts of Question 6
- 6(a) Nitrophenol acidity5 marks
- 6(b) Benzene and cyclooctatetraene orbitals5 marks
- 6(c) Aldehyde electrophilicity5 marks
- 6(d) Carbocation stability5 marks
- 6(e) Steric inhibition of resonance5 marks
- 6(f) Cyclopropenone dipole5 marks
- 6(g) SN1 and aromatic cations5 marks
- 6(h) Exhaustive methylation of piperidine5 marks