Indian Forest Service (Mains), Chemistry optional · 2021 · Paper II
Q3(b)(i). Carbon–carbon bond formation from a bromoester
Question
Convert EtO₂CCH=CHCH(Br)CH₃ into EtO₂CCH=CHCH(CH₃)C(OH)(CH₃)₂; identify A and B in the given scheme and explain the reaction.
Answer in brief
A is acetone and B is activated Zn in dry ether, followed by acidic work-up.
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CoversReformatsky reactionorganozincβ-hydroxy esteracetoneallylic bromoester
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