The compound Advantame is a sweetener that tastes approximately 25000 times sweeter than sucrose. [Figure: Structure of Advantame (C23H29NO4)]

1. (a)Advantame is optically active. On the diagram of Advantame, circle all the chiral carbon atoms.[1]
2. (b)(i)Suggest possible reagents and conditions for this decomposition.[1]
3. (b)(ii)Name the type of reaction occurring.[1]
4. (b)(iii)Draw the structure of L in the box above.[1]
5. (c)(i)Aqueous bromine was added dropwise to a solution of J until the bromine was in excess. State what you would observe.[1]
6. (c)(ii)J has the molecular formula C₁₄H₁₉O₆N. Use this formula to write an equation for the reaction of excess aqueous sodium hydroxide with one mole of J.[2]
7. (d)(i)State what you would observe when an excess of aqueous bromine is added to a solution of K.[1]
8. (d)(ii)K can be polymerised. Draw the structure of the polymer showing two repeat units. The linkage between the monomer units should be fully displayed.[2]
9. (e)(i)State how many different carbon environments are present in K.[1]
10. (e)(ii)The chemical shifts, δ, due to two of the carbon atoms x and y present in K are given in the table. carbon atom δ/ppm x 130 y 170 On the structure of K, circle and label two carbon atoms which could correspond to x and y.[1]

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