Spearmint contains carvone, while caraway seeds contain a stereoisomer of carvone. If either isomer is treated with hydrogen over a nickel catalyst, a mixture of isomers with structural formula X is produced.
(a(i))[1]
State which type of stereoisomerism carvone is capable of showing. Explain your answers.
(a(ii))[2]
Using molecular formulae, write an equation for the conversion of carvone to X.
(b(i))[1]
Name the mechanism in step 1.
(b(ii))[2]
What type of reaction is taking place in the following steps?
step 3
step 5
(b(iii))[6]
Suggest reagents and conditions for each of the steps below.
step 1
step 2
step 3
step 4
(c(i))[1]
State the reagents and conditions required for this reaction.
(c(ii))[2]
Complete the part structure so that it shows the isomer of X that is most likely to be obtained in this reaction.
Worked solution & mark scheme
This 15-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Optical, because it contains a chiral carbon bonded to four different groups” …