= Solution
\Image[/past-exam-of-the-chemistry-course-of-the-year-3-of-the-natural-sciences-course-of-the-university-of-cambridge/2022/paper-3-q39-sidechain-assignments.png]
{title=The cinnamoyloxymethyl and tertiary-alcohol side chains, with their spectral assignments}
The two substituents are \b[$\mathrm{-CH_2-O-C(O)-CH=CH-Ph}$], with the <alkene> E, and \b[$\mathrm{-C(OH)(CH_3)_2}$]. The free bond at the left of each drawing attaches to the <cyclohexene>.
The A-D <COSY> correlation and $16.2\,\mathrm{Hz}$ coupling identify the trans cinnamate double bond. Five aromatic protons and four phenyl-carbon environments identify its monosubstituted phenyl ring. F is a two-proton OCH$_2$ signal; its <HMBC> correlation to <carbonyl> 1 joins that methylene through <oxygen> to the <ester>. The two three-proton singlets N/O, their correlations to oxygenated quaternary <carbon> 10, and the missing OH resonance give the tertiary-alcohol substituent.
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