Q7(c)(ii). Three isomeric carbonyl compounds C₅H₁₀O
Three isomeric compounds having MF C₅H₁₀O give positive 2,4-DNP test and display the following NMR spectral characteristics. Identify the compounds. Among them, one isomeric compound on treatment with KOH (concentrated) gives two products. Write their structures also: (1) A triplet at δ 1.05 and a quartet at δ 2.47; (2) Two singlets; (3) A doublet at δ 1.0, a singlet at δ 2.1 and a septet at δ 2.2.
Model answer
The free solution for 2022 answers questions 1, 4, 5, 6 and 8, the ones picked in its time plan. Question 7 is answered in full in the Chemistry Paper II, 2021 to 2025 book, with every part of every paper.
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UPSC Civil Services (Main) Chemistry Paper II: Model Answers 2021 to 2025
- All eight questions of each paper, with the question printed above its answer
- Mechanisms drawn out and labelled on the scheme
- Topic-wise weightage and a topic-wise index
Covers2,4-DNP testC₅H₁₀O isomersNMR splittingCannizzaro reactionpivalaldehyde
All parts of Question 7
- 7(a) Secondary structures of proteins compared with tertiary structure15 marks
- 7(b)(i) Butanoyl chloride with 2 NaBH₄, then H₃O⁺10 marks
- 7(b)(ii) But-2-yne with sodium in liquid ammonia5 marks
- 7(c)(i) Compound A (M = 102) and its cleavage products B and C10 marks
- 7(c)(ii) Three isomeric carbonyl compounds C₅H₁₀O10 marks