Indian Forest Service (Mains), Chemistry optional · 2021 · Paper II
Q3(d)(i). Haworth synthesis of a methoxytetralone
Question
Identify A, B and C in the sequence anisole + A/SnCl₄ → p-MeOC₆H₄COCH₂CH₂CO₂H —B→ p-MeOC₆H₄(CH₂)₃CO₂H —C→ the drawn methoxytetralone. [structure of the tetralone given in the paper]
Answer in brief
A is succinic anhydride; B can be Zn(Hg)/HCl; C can be polyphosphoric acid and heat.
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CoversHaworth synthesisFriedel–Crafts acylationsuccinic anhydrideClemmensen reductiontetralone
All parts of Question 3
- 3(a)(i) Hydrogen exchange in cyclopropyl ketones5 marks
- 3(a)(ii) Strongly shielded internal methyl groups5 marks
- 3(b)(i) Carbon–carbon bond formation from a bromoester5 marks
- 3(b)(ii) Intramolecular aldol condensation5 marks
- 3(c)(i) ESR resonance field5 marks
- 3(c)(ii) Aromaticity of five-membered heterocycles5 marks
- 3(d)(i) Haworth synthesis of a methoxytetralone5 marks
- 3(d)(ii) Cyanide substitution on a nitroaryl halide5 marks