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Chemistry LibreTexts

Michael Additions & Robinson Annulation

Enolates undergo 1,4 addition to α, β-unsaturated carbonyl compounds is a process called a Michael addition.  The reaction is named after American chemist Arthur Michael (1853-1942).

Examples of Michael Additions

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Robinson Annulation

Many times the product of a Michael addition produces a dicarbonyl which can then undergo an intramolecular aldol reaction.  These two processes together in one reaction creates two new carbon-carbon bonds and also creates a ring. Ring-forming reactions are called annulations after the Latin work for ring annulus. The reaction is named after English chemist Sir Robert Robinson (1886-1975) who developed it. He received the Nobel prize in chemistry in 1947. Remember that during annulations five and six membered rings are preferred. 

Examples of Robinson Annulations

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