Skip to content
CIE Jun 2016 v2 Paper 4 Q9
Answers available below
Show answer
Question
1
2
3
4
5
6
7
8
9
10
![The anti-inflammatory drug ibuprofen can be synthesised from benzene via the following six steps. 18 PMT step 1 step 2 step 3 OH CN step 4 step 5 CO2H step 6 CO2H ibuprofen (a) Draw circles around any chiral carbon atoms in the above five formulae. (b) Suggest the structures of compounds H and J and draw them in the boxes above. [1] [2] (c) Suggest reagents and conditions for steps 1-6. step 1step 2step 3step 4step 5step 6[6] (d) Name the mechanism of step 1 and state the type of reaction for step 6. step 1step 6[2] [Total: 11]UCLES 2016 9701/42/M/J/16<br />](https://learnah.org/wp-content/uploads/2018/08/June_2016_v2_QP_-_Paper_4_CIE_Chemistry_A-level_9.jpg)
![Page 10 Mark Scheme Syllabus Paper Cambridge International AS/A LevelMay/June 2016 9701 42 Question (ii) x = Hat(Ca) + IE(1) + IE(2)2Hhyd(H Answer ) + Hhyd(Ca 2+ )2IE(H)E(H-H) x = 178 + 590 + 1150 + 2(1090)15762(1310)436 x = 534 kJ mol 1 (c) CH3CO2H is incompletely ionised / weak acid / weaker acid enthalpy change of ionisation (of CH3COOH) is +2 kJ mol 1 or energy needed to ionise / dissociate (CH3COOH) (a) OH CN COCambridge International Examinations 2016 PMT Marks [Total: 10]<br />
Page 11 Mark Scheme Syllabus Paper Cambridge International AS/A LevelMay/June 2016 9701 42 Question (b) Answer Marks PMT J1 J2 (c) step 1: (CH3)2CHCH2Cl + Al Cl 3 (+ heat) step 2: CH3COCl + Al Cl 3 (+ heat) step 3: HCN + NaCN or HCN + base or HCN + CN (steps 4 and 5 could be reversed on J) If J1 step 4 then step 5 J2 step 5 then step 4 step 4: H3O + heat / aqueous HCl + heat step 5: conc H2SO4 + heat / conc H3PO4 + heat or Al 2O3 + heat step 6: H2 + Ni (+ heat) (d) step 1: electrophilic substitution or alkylation step 6: reduction / hydrogenation / additionCambridge International Examinations 2016 [Total: 11]<br />](https://learnah.org/wp-content/uploads/2018/08/June_2016_v2_MS_-_Paper_4_CIE_Chemistry_A-level_9-0.jpg)
