Part 6: SYNTHESIS

Answers to the synthesis problems are given below.  These answers have been selected as they are short and efficient, but there are probably other reasonable solutions.  Note some targets have specific stereochemistry that must be considered.

When planning syntheses, one should try to work backwards by functional group analysis. The diagrams show the "retrosynthesis" - the design or plan and then below that the reaction scheme step-by-step (as required in the question).

The key reasons students did not get full marks were:
1. using the wrong reagents for the task at hand or confusing similar but different reagents (e.g. Na / NH3 and NaNH2)
2. not showing the synthesis of materials such as simple alkyl halides or alcohols from hydrocarbons
3. using routes with poor yields due to inefficient routes (e.g. lack of control) or using routes that were unnecessarily long.


Note : reversing the order of the steps in the synthesis significantly reduces the selectivity of the scheme since multiple regioisomers will be possible.











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