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Michael Additions & Robinson Annulation

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    5141
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    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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    File:/C:\Users\farmers\AppData\Local\Temp\msohtmlclip1\01\clip_image004.png

    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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    Contributors


    Michael Additions & Robinson Annulation is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.

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