Indian Forest Service (Mains), Chemistry optional · 2021 · Paper II
Q6(a)(i). Malonic ester ring synthesis
Question
Complete diethyl malonate + 1,3-dibromopropane with NaOEt, followed by hydrolysis and heating; show the mechanism with arrows and charges.
Answer in brief
The product after acidification and decarboxylation is cyclobutanecarboxylic acid.
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Coversmalonic ester synthesiscyclobutanecarboxylic acidintramolecular alkylationdecarboxylation1,3-dibromopropane
All parts of Question 6
- 6(a)(i) Malonic ester ring synthesis5 marks
- 6(a)(ii) Wittig olefination5 marks
- 6(b)(i) Tertiary protein structure5 marks
- 6(b)(ii) End-group content of polystyrene5 marks
- 6(c)(i) Cyclization of a beta-hydroxy phenethylamide5 marks
- 6(c)(ii) Terylene from p-xylene5 marks
- 6(d) Fischer indole synthesis5 marks
- 6(e) Acid equivalent of nylon-6,65 marks