BIFUNCTIONAL CHEMISTRY (06522)
Contents Overview
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Keto-enol tautomerisation
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Reactions of enols: C-Hal and C-N=O bond formation
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Reactions of enols and enolates with aldehydes and ketones
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Reactions of enolates with esters and acid chlorides
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Reactions of enolates with alkylating agents
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Conjugate addition reactions and the Michael reaction
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Reactions of enol / enolate-like molecules such as enamines, silyl enol ethers and nitronates
Learning outcomes: At the end of the course you will be able to:
1. Keto-enol tautomerisation
Demonstrate the mechanisms of both acid and base-catalysis of tautomerisation and draw
tautomeric form(s) of a given molecule. Discuss factors controlling tautomeric stability.
2. Enols and enolates: C-Hal and C=N-OH bond formation
Work out the products arising from the reaction of enols or enolates with halogens and the
nitrosonium (NO+) ion.
3. Enols and enolates: the aldol, Claisen and Dieckmann reactions
Work out the product(s) arising from the reaction of enols or enolates with aldehydes,
ketones and esters.
4. Crossed condensation reactions
Work out the product(s) arising from the reaction of an enolate from one carbonyl compound
with a different carbonyl compound, identifying factors which give rise to combinations
producing product(s) with either high or low selectivity.
5. Lithium enolates and enolates of 1,3-dicarbonyl compounds
Work out the product(s) arising from the reaction of lithium enolates with alkyl halides.
Demonstrate the use of stable enolates from β-keto esters and 1,3-diesters for alkylation
reactions, with a subsequent decarboxylation process.
6. Conjugate addition reactions
Work out the product(s) arising from the conjugate addition reactions of stable enolates with
α,β-unsaturated carbonyl compounds.
7.
Enamines and silyl enol ethers
Compare the reactions of simple enamines and enol ethers with those of enols and enolates.
8. Nitroalkanes and cyanoalkanes
Compare the reactions of the anions of nitroalkane and cyanoalkanes with those of enolates.
Suggested reading

Organic Chemistry, J. Clayden, N. Greeves, S. Warren and P. Wothers, Oxford University
Press. Chapters 21, 26, 27, 28, 10, 29 (1st Edition) or Chapters 20, 22, 25, 26 and in part 17
and 28 (2nd Edition). Background / revision: Chapters 6, 12, 14 (reactions of aldehydes,
ketones and esters – lectures from year 1) (1st Edition) or Chapters 6, 10 and 11 (2nd ed.).

Also recommended is Chemistry Of The Carbonyl Group, A Programmed Approach To
Organic Reaction Mechanisms, S. Warren (Wiley, 1974)

Bifunctional Compounds, RS Ward, OP (Oxford Primer No. 17): useful in parts

Similar chapters will be found in all Organic Chemistry texts, e.g. T. Solomons & C. Fryhle,
F. Carey, Maitland Jones etc.
See http://www.hull.ac.uk/php/chsanb/teaching.html for a set of these notes and past exam paper
questions with answers. Work book problems must be completed as the course progresses.
Dr AN Boa, C120b, a.n.boa@hull.ac.uk
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Problems
Lecture 1: Draw all possible enols of the following compounds.
Lecture 2: Explain the following observations.
The optical rotation [α]D of compound A goes from -96° to 0° after treatment with sodium methoxide,
and the optical rotation of B changes from +66° before to +45° after recrystallization from acetic acid.
Lecture 3: Work out the product(s) from the following cyclisations.
Lecture 4: Work out the product(s) from the following condensations.
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Lecture 5: Work out the product from the following sequence.
Lecture 6: Work out the product from the following sequence.
Lecture 7: Work out the product from the following reactions.
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SUMMARY OF KEY REACTIONS
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