Indian Forest Service (Mains), Chemistry optional · 2025 · Paper II
Q3(b). Knoevenagel condensation
Question
Give products and mechanism for diethyl malonate with acetaldehyde and catalytic piperidine.
Answer in brief
The principal condensation product is diethyl ethylidenemalonate, CH₃CH=C(CO₂Et)₂, plus water.
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CoversKnoevenagel condensationdiethyl malonatepiperidine catalystactive methylene compoundiminium catalysis
All parts of Question 3
- 3(a) Stevens rearrangements of two ylides10 marks
- 3(b) Knoevenagel condensation10 marks
- 3(c) Erlenmeyer–Plöchl azlactone synthesis10 marks
- 3(d) Regioselective ketone alkylation10 marks