Q7(a). λmax of three dienones by Woodward–Fieser rules
Calculate the value of λmax in the following compounds (A, B and C) using Woodward–Fieser rules. [structures of the three dienones given in the paper]
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The free solution for 2024 answers questions 1, 3, 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
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CoversWoodward–Fieser rulesλmax calculationdienoneUV spectroscopyhomoannular dieneexocyclic double bond
All parts of Question 7
- 7(a) λmax of three dienones by Woodward–Fieser rules15 marks
- 7(b) X, Y and Z from an N-Boc piperidine aldehyde15 marks
- 7(c)(i) Two isomeric esters C₁₀H₁₂O₂10 marks
- 7(c)(ii) Fragment ions m/z 58 and m/z 9210 marks