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Addition of Secondary Amines to Form Enamines

  • Page ID
    742
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    Most aldehydes and ketones react with 2º-amines to give products known as enamines. It should be noted that, like acetal formation, these are acid-catalyzed reversible reactions in which water is lost. Consequently, enamines are easily converted back to their carbonyl precursors by acid-catalyzed hydrolysis.

    OrganicCore_AldehydesKetones51.png

    Mechanism

    1) Nuleophilic attack

    OrganicCore_AldehydesKetones52.png

    2) Proton transfer

    OrganicCore_AldehydesKetones53.png

    3) Protonation of OH

    OrganicCore_AldehydesKetones54.png

    4) Removal of water

    OrganicCore_AldehydesKetones55.png

    5) Deprotonation

    OrganicCore_AldehydesKetones56.png

     

    Reversibility of Enamines

    OrganicCore_AldehydesKetones57.png

     

    Example

    OrganicCore_AldehydesKetones58.png

    Problems

    1) Please draw the products for the following reactions.

    OrganicCore_AldehydesKetones59.png

    2) Please give the structure of the reactant needed to product the following product

    OrganicCore_AldehydesKetones60.png

    Answers

    1)

    OrganicCore_AldehydesKetones61.png

    2)

    OrganicCore_AldehydesKetones62.png

     

    Contributors

     


    Addition of Secondary Amines to Form Enamines is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.

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