Reactions at the carbonyl group: every question, 2016 to 2025

Notes: Molecular rearrangements (full notes) · short notes

Notes: Carbonyl additions and condensations (full notes) · short notes

2025

• Q6(d) Michael addition of a cyclic 1,3-dione to cyclohex-2-enone4 marks Answered
• Q7(b)(ii) Furil to furilic acid: benzilic acid rearrangement5 marks Answered
• Q7(c)(i) 4-Methoxybenzaldehyde with NaCN: benzoin condensation5 marks Answered
• Q7(c)(ii) Norrish Type II against Type I in two ketones5 marks Answered
• Q8(b)(i) Wittig alkene, then epoxide and diol5 marks Question only
• Q8(b)(ii) Ozonolysis, then intramolecular aldol condensation5 marks Question only
• Q9(a)(i) Dieckmann condensation, then NaBH₄ reduction5 marks Answered

2024

• Q6(c) Phenylglycine and mandelic acid from benzaldehyde4 marks Answered
• Q6(d) Coumarin and 3-acetylcoumarin from salicylaldehyde4 marks Answered
• Q7(a)(i) Schmidt reaction of a cyclohexanone with an alkyl azide5 marks Answered
• Q7(a)(ii) Robinson annulation of 2-methylcyclohexane-1,3-dione5 marks Answered
• Q8(a)(i) 2-Acetylbenzaldehyde with KCN: internal hydride shift to a lactone5 marks Question only
• Q8(c) Hexane-2,5-dione with acid: Paal–Knorr furan synthesis5 marks Question only
• Q8(d) Ozonolysis, then intramolecular aldol condensation10 marks Question only
• Q9(b) Dieckmann condensation, then hydrolysis and decarboxylation5 marks Answered
• Q9(d)(ii) Robinson annulation to a spiro enone5 marks Answered

2023

• Q6(d) Benzaldehyde and ethane-1,2-dithiol: a 1,3-dithiolane4 marks Answered
• Q7(d) Intramolecular aldol condensation of a dialdehyde10 marks Answered
• Q8(d) Double Mannich reaction: ring closure to a 4-piperidone10 marks Question only
• Q9(d) Products of five reactions5 marks Question only
• Q10(a) Perkin reaction, then three steps to 2-methylindane10 marks Answered

2022

• Q6(a) Cyclohexanone: self-condensation with NaOH, none with LDA4 marks Answered
• Q6(b) Ethyl acetoacetate with cyclohexanone: Knoevenagel condensation4 marks Answered
• Q7(b) Ketone with diethyl carbonate: crossed Claisen condensation5 marks Answered
• Q7(c) Lactic acid from ethanal through the cyanohydrin5 marks Answered
• Q7(d) Phenyl acetate to A, B, C, D: Reimer–Tiemann and Wittig reactions10 marks Answered
• Q9(a) Gramine route to indole-3-acetic acid; photolysis of cyclodecanone10 marks Question only
• Q9(b) Cannizzaro reaction: effect of para substituents on the rate5 marks Question only
• Q9(d) Four conversions: structures of the products10 marks Question only
• Q10(a) Reformatsky reaction and dehydration; Doebner synthesis10 marks Answered

2021

• Q6(f) Norrish Type II reaction of two aryl alkyl ketones6 marks Answered
• Q7(a) Phenol to salicylaldehyde to a coumarin ester10 marks Answered
• Q8(a) Cyclohexanone: Wolff–Kishner reduction and Reformatsky reaction10 marks Question only
• Q8(c) Cyclohexane-1,2-dione and NaOH: benzilic acid ring contraction4 marks Question only
• Q9(a) Benzaldehyde: Cannizzaro, Claisen–Schmidt and Perkin reactions12 marks Question only

2020

• Q6(c) Cyanohydrin formation and hydrolysis4 marks Answered
• Q6(d) Doebner condensation4 marks Answered
• Q8(a) Robinson annulation10 marks Answered
• Q8(b) Benzilic acid rearrangement of phenanthrenequinone10 marks Answered

2019

• Q6(j) Cyanohydrin acyl-anion equivalent4 marks Answered
• Q9(a) Product A of an aldehyde condensation with mechanism10 marks Question only

2018

• Q6(b) Conjugate addition and dehydrogenation4 marks Answered
• Q6(e) Double Michael addition and Dieckmann closure4 marks Answered
• Q7(d) Unsymmetrical benzil synthesis5 marks Answered
• Q8(d) pKa order of four carbonyl compounds5 marks Question only
• Q8(e) Identify A (C₁₀H₁₆O) and B from tests and ozonolysis10 marks Question only

2017

• Q6(c) Aldehyde electrophilicity5 marks Answered
• Q7(a) Complete two carbonyl reactions with mechanism10 marks Question only
• Q7(b) Two conversions in good yield10 marks Question only
• Q7(c) Identify A and B in a reaction sequence10 marks Question only
• Q9(b)(i) Wittig alkene synthesis5 marks Answered
• Q9(b)(ii) Reformatsky reaction5 marks Answered

2016

• Q7(c) Grignard addition to a keto ester4 marks Answered
• Q7(e) Cannizzaro reaction4 marks Answered
• Q9(b) Robinson annulation5 marks Answered
• Q11(b) Ylides and Wittig selectivity5 marks Answered
• Q11(c) Substituent effects in benzoin condensation5 marks Answered