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Sample problem: (sd-61)

How would you prepare the following compound by an enamine

synthesis?

Alkylation of the -carbon: (sd-62)

THE MICHAEL REACTION

Addition of enolate ion to the -carbon of , -unsaturated carbonyl

compound Michael Reaction.

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Stork Enamine Reaction (Sd-64)

When an enamine is used as a nucleophile in place of an enolate in

a Michael reaction, the reaction is called Stork Enamine Reaction.

ALDOL CONDENSATION: (sd-65)

A reaction between two molecules of RCHO/RCOR with -

hydrogen in basic condition -hydroxy aldehyde or -hydroxy

ketone.

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Dehydration of Aldol addition product (sd-66)

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Dehydration sometimes occurs under the conditions in which the

aldol addition is carried out (without additional heating)(sd-67).

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Crossed Aldol Condensations: (sd-68)

Condensation between two carbonyl compounds (only one of the

carbonyl compounds has -hydrogen)

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Intramolecular Aldol reactions: Certain dicarbonyl compounds

when treated with base undergo intramolecular aldol

reactionscyclic products (5/6-membered).

MECHANISM:

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Synthesis using aldol condensations (sd-70)

Aldol condensation 1. -hydroxy aldehyde or ketone

2. --unsaturated aldehyde/ketone

Therefore look for these two functional groups and decide which

aldehydes/ketones must be used for the starting materials.

Knoevenagel condensation (sd-71)

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The Claisen condensation: (73)

Condensation involving molecules of an ester (with -H) in the

presence of base a -keto ester.

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Crossed Claisen condensation: ( sd-74)

Condensation between two different esters; Best results (to avoid

mixtures) are obtained if only one of the esters has -H)

Condensation between ketones and esters (either contain -H or

not)

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Both having H- :(sd-74a)

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The Robinson Annulation (sd-79)

A ring forming reaction that involves:

i) A Michael Reaction- to form a 1,5-diketone

ii) 1,5-diketone undergoes an intramolecular aldol addition

cyclic compound

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