Part 7: 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 schematic of the solution is shown below. The information from the question is given in black. Deductions directly from this information are given in red. Points that provide potential key information are shown in green which leads to the structures.

The logical thought pathway would be based on identifying C and E from the ozonolysis results. Once they are determined, one can determine B and then the other structures. There are, of course, other possible thought pathways.

Common mistakes:

• incorrect stereochemistry for D and F, not recognising that B had to be a symmetrical alkyne.