Compound D shows the following IR spectrum. 100 80 60 %T 40 3037 1650 20 1739 1678 4000 3000 2000 1500 1000 500 wavenumber, cm-1 (i) Match the spectrum with any of the suitable compounds listed below. ОН OH -CEN NEC- II II IV VI (ii) Explain your answer in b(i).

A molecule produces two molecular ions with a m/z of 152 and 154 and a base peak with a m/z of 73. The IR and ¹H NMR spectra are shown below. Draw the structure that best fits this data. 4000 1H 11 10 3000 9 8 2000 7 1500 Wavenumbers (cm) + 6 5 2H 1000 2H 2 1 500 ppm of Q Q

18. Proton NMR spectra are given together with molecular formula. Propose a structure that corresponds to each spectrum. (Hint: Find IHD first). Assign peaks to show which protons give rise to which peaks 10 10 10 (b) C4H8O₂ Offset: 2.4 ppm (b) C₂H100 9 (c) CsHgO₂ 9 8 8 7 7 6 6 6 5 8 (ppm) OHz 5 8 (ppm) 4 3.08 2.98 2.88 2.78 8 (ppm) 50Hz 4 4 3 2 1 0 0

Please clearly label the answer and explain thoroughly. Thanks in advance.