Q9(a). Benzaldehyde: Cannizzaro, Claisen–Schmidt and Perkin reactions
Predict the product(s) when benzaldehyde is allowed to react with different reactants under given conditions: C₆H₅CHO, NaOH → I; CH₃CHO, NaOH → II; CH₃CO–O–COCH₃, NaOCOCH₃ → III. Also provide suitable mechanism.
Model answer
The free solution for 2021 answers questions 1, 2, 5, 6, 7 and 10, the ones picked in its time plan. Question 9 is answered in full in the Geo-Scientist Chemistry Paper III, 2021 to 2025 book, with every part of every paper.
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UPSC Combined Geo-Scientist (Main) Chemistry Paper III: Model Answers 2021 to 2025
- All ten questions of each paper, with the question printed above its answer
- Instruments drawn as labelled diagrams, numericals worked with units
- Topic-wise weightage and a topic-wise index
CoversCannizzaro reactionClaisen–Schmidt condensationPerkin reactionbenzaldehydecinnamic acid
All parts of Question 9
- 9(a) Benzaldehyde: Cannizzaro, Claisen–Schmidt and Perkin reactions12 marks
- 9(b) 1-Methylcyclopentene to 1- and 2-methylcyclopentanol8 marks
- 9(c) Chorismate to prephenate; a steroidal diene opened by light10 marks