1 Nucleophilic reactions involving enolate anions Aldehydes, Ketons and other carbonyl compounds...

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Transcript of 1 Nucleophilic reactions involving enolate anions Aldehydes, Ketons and other carbonyl compounds...

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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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Nucleophilic reactions involving enolate anions

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Nucleophilic reactions involving enolate anions

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Nucleophilic reactions involving enolate anions

Enolate anionConjugated base

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Nucleophilic reactions involving enolate anions

Hydrogen Exchange

Racemization

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Nucleophilic reactions involving enolate anions

Conjugation

Enol-Form -> Keto-Form

Progesterone(female sex hormone)

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Nucleophilic reactions involving enolate anions

Halogenation

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Nucleophilic reactions involving enolate anions

Alkylation of enolate anion

Enolate anion acting as carbanion nucleophiles in SN2 reaction

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Nucleophilic reactions involving enolate anions

Alkylation of enolate anion

Reaction not possible with aryl halides

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Nucleophilic reactions involving enolate anions

Alkylation of enolate anion

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Nucleophilic reactions involving enolate anions

Alkylation of enolate anion

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Nucleophilic reactions involving enolate anions

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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Nucleophilic reactions involving enolate anions

Addition-dehydration: Aldol reaction

mixed aldol reaction

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Nucleophilic reactions involving enolate anions

Addition-dehydration: Aldol reaction

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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Nucleophilic reactions involving enolate anions

Addition-dehydration: Aldol reaction

Intramolecular aldol reaction

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Nucleophilic reactions involving enolate anions

Other stabilized anions as nucleophiles: nitriles and nitromethane

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Nucleophilic reactions involving enolate anions

Other stabilized anions as nucleophiles: nitriles and nitromethane

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Nucleophilic reactions involving enolate anions

Other stabilized anions as nucleophiles: nitriles and nitromethane

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Nucleophilic reactions involving enolate anions

Enamines as nucleophiles

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Nucleophilic reactions involving enolate anions

Enamines as nucleophiles

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Nucleophilic reactions involving enolate anions

Enamines as nucleophiles

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Nucleophilic reactions involving enolate anions

Enolate anions from carboxylic acid derivates

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Nucleophilic reactions involving enolate anions

Enolate anions from carboxylic acid derivates

base

More favourable with ketons and aldehydes

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Nucleophilic reactions involving enolate anions

Enolate anions from carboxylic acid derivates