1 Nucleophilic reactions involving enolate anions Aldehydes, Ketons and other carbonyl compounds having H on α-C -> in equilibrium (in solution) -> Keto-Enol

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Nucleophilic reactions involving enolate anions

Aldehydes, Ketons and other carbonyl compounds having H on α-C -> in equilibrium (in solution) -> Keto-Enol tautomerization

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Enolate anionConjugated base

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Hydrogen Exchange

Racemization

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Conjugation

Enol-Form -> Keto-Form

Progesterone(female sex hormone)

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Halogenation

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Alkylation of enolate anion

Enolate anion acting as carbanion nucleophiles in SN2 reaction

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Reaction not possible with aryl halides

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Addition-dehydration: Aldol reaction

Carbonyl compounds reacting as electrophiles -> aldol reaction

Aldehydes are better electrophiles than ketons-> aldol reaction more favourable with aldehydes

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mixed aldol reaction

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Product from aldol reaction dehydrates by heating in acid or base -> α,β unsaturated carbonyl compound

Under basic conditions -> E1cb (elimination-unimolecular-conjugated base)

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Intramolecular aldol reaction

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Other stabilized anions as nucleophiles: nitriles and nitromethane

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Enamines as nucleophiles

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Enolate anions from carboxylic acid derivates

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base

More favourable with ketons and aldehydes

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Documents

1 Nucleophilic reactions involving enolate anions Aldehydes, Ketons and other carbonyl compounds having H on α-C -> in equilibrium (in solution) -> Keto-Enol