Part 8: 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 which are linked via the blue arrows to show the path required to work them all out. There are, of course, other possible thought pathways.


Due to limited time at present a simple of list of the names for the answers is provided.... as and when time allows the complete derived solution will be posted.

In an exam, a drawing of the structure is all that is normally required.

A = (Z)-3-methyl-2-pentene

B = 2-ethyl-1-butene

C = (E)-3-methyl-2-pentene

D = 2-bromo-2-ethylbutane

E = 2-ethylbutan1-ol

F = 5-ethylhept-2-yne

G = 3-bromo-2-ethylbut-1-ene

H= 3-ethoxy-2-ethylbut-1-ene

I= (E)-1-ethoxy-2-ethylbut-2-ene

J = 4-ethyl-4,5-dimethylcyclohexene (methyl groups are trans)

Key steps : Deriving F from the ozonolysis data