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. This is also presented
in several parts, where each diagram has more information added to it.
The idea behind this is to encourage students to see how to work towards the answer
by building up the answer from the information in the question gradually.
Diagram
1 just gives all the information from the question in black with
no interpretation. You can use this to try to solve the problem
based on that information.
Diagram
2 gives the basic information from the question in black and deductions
directly from this information are indicated by red arrows and with blue text plus it identifies the functional groups
and points that provide potential key information by green arrows and key initial
structures.
Diagram
3 gives the completed solution with the structures in blue. In this problem
the are several routes to connect the structures.
Key steps are :
- A
has only one type of H
- Carbocation rearrangements lead
to D and F
- E
can de deduced from NMR