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Crossed Aldol Reaction

  • Page ID
    39391
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    Crossed aldol reaction is a variation of aldol reaction.

    aldol reaction:

    crossedaldolreaction1.png

    crossed aldol reaction:

    crossedaldolreaction2.png

    eg:

    crossedaldolreaction3.png

    Mechanism:
    Step 1: The hydroxide ion deprotanates the enolizable aldehyde reversibly.

    crossedaldolreaction4.png

    Step 2: Enolate ion 1 preferentially adds to the non-enolizable aldehyde, which has the sterically less hindered and, therefore, more accessible carbonyl carbon.

    crossedaldolreaction5.png

    Step 3: Alkoxide ion 2 is protonated by water.

    crossedaldolreaction6.png

    see also crossed aldol condensation


    This page titled Crossed Aldol Reaction is shared under a All Rights Reserved (used with permission) license and was authored, remixed, and/or curated by Gamini Gunawardena via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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