UPSC Combined Geo-Scientist, Mains · 2020 · Mains Paper III
Q6(a). Dichlorocarbene ring expansion
Question
Complete the reaction of 2-methoxynaphthalene with CHCl₃/KOH.
Answer in brief
The characteristic ring-expansion product is 2-chloro-4,5-benzotropone.
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CoversDichlorocarbene ring expansionCarbene chemistry
All parts of Question 6
- 6(a) Dichlorocarbene ring expansion4 marks
- 6(b) Anionic polymerisation of substituted styrenes4 marks
- 6(c) Cyanohydrin formation and hydrolysis4 marks
- 6(d) Doebner condensation4 marks
- 6(e) Hydration with skeletal rearrangement4 marks
- 6(f) Diene reactivity in Diels–Alder reactions4 marks
- 6(g) Norrish II reactivity4 marks
- 6(h) UV maximum of a dienone4 marks
- 6(i) Carbonyl stretching frequencies4 marks
- 6(j) Distinguishing three carbonyl compounds by proton NMR4 marks