Part 9 : STRUCTURE DETERMINATION

Note that these types of questions are often the most difficult on the examination. This is because they are holistic in that they require a good understanding of the reactions and the concepts and the ability to apply those concepts. They can't be memorised, they require understanding and ability to apply. Hence they help discriminate those who truly understand from those who have memorised and will soon forget.

A full schematic of the full solution is presented below.

The key structure (where we know the most) is E. The spectral data should give the structure of E (HNMR shows ethyl group and vinyl H). Once we know E, we can determine C. From C we can deduce D and F. From C we can work out A (invoke rearrangement during SN1) and use the stereochemical information provided. Once we have A, that only leaves B.