Q5(e). Matching three sets of IR and NMR data with five structures
Given below are the IR and NMR spectral characteristics of three compounds: (i) IR: 1750 cm⁻¹; NMR: δ 2.0 (s, 3H), 5.1 (s, 2H) and 7.3 (s, 5H). (ii) IR: 1740 cm⁻¹; NMR: δ 3.5 (s, 3H), 3.6 (s, 2H) and 7.4 (s, 5H). (iii) IR: 3200–2800 (various bands) and 1700 cm⁻¹; NMR: δ 2.75 (t, 2H), 2.95 (t, 2H), 7.4 (s, 5H) and 12.0 (s, 1H). Match each of these spectral data with one of the following structures (1) to (5). [five structures given in the paper]
Answer in brief
(i) = (4) benzyl acetate; (ii) = (2) methyl phenylacetate; (iii) = (5) 3-phenylpropanoic acid. Structures (1) and (3) match none.
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CoversIR and NMR structure determinationbenzyl acetatemethyl phenylacetate3-phenylpropanoic aciddegree of unsaturation
All parts of Question 5
- 5(a) Nucleosides, nucleotides and the primary structure of DNA and RNA10 marks
- 5(b) Photolysis of 2-methylcyclohexanone in solution10 marks
- 5(c)(i) 1-Ethynylcyclopentanol from acetylene5 marks
- 5(c)(ii) Products W, X, Y and Z from toluene5 marks
- 5(d) N–H stretching of amines in IR; alcohols in PMR10 marks
- 5(e) Matching three sets of IR and NMR data with five structures10 marks