Question 23M.3.HL.TZ1.19
| Date | May 2023 | Marks available | [Maximum mark: 5] | Reference code | 23M.3.HL.TZ1.19 |
| Level | HL | Paper | 3 | Time zone | TZ1 |
| Command term | Deduce, State | Question number | 19 | Adapted from | N/A |
The chemotherapy drug Taxol is now manufactured using a chiral auxiliary and 10-deacetybaccatin III instead of the bark of Pacific yew trees.
A chiral auxiliary used in the synthesis of Taxol is trans-2-phenylcyclohexanol. Deduce and label with asterisks (*) the positions of the two chiral carbon atoms in the molecule.
[2]
one for each carbon correctly identified
Apply ‘list principle’ if any answer has more than two carbon atoms marked.
State one natural source of 10-deacetylbaccatin III now used to synthesize Taxol.
[1]
needles «of European» yew «tree» ✓
State two principles of green (sustainable) chemistry in drug manufacturing, other than using less hazardous or toxic reactants.
[2]
Any two of:
energy efficiency ✓
prevention of waste/recycling ✓
atom economy/more efficient processes ✓
safer/reduced use of solvents ✓
design for degradation ✓
more sustainable sourcing of reactants/feedstock ✓
Accept specific examples.
