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Active Methylene Compound

  • Page ID
    16564
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    An active methylene compound is a compound that has the following general structural formula.

    activemethylenecompound1.png

    E1, E2 = a functional group that withdraws electrons by resonance

    eg:

    activemethylenecompound2.png

    The conjugate base of an active methylene compound is highly resonance stabilized.

    eg:

    activemethylenecompound3.png

    Consequently, active methylene compounds are highly acidic and can be deprotonated, for all practical purposes, irreversibly, using common strong bases, such as the hydroxide ion or alkoxide ions.

    activemethylenecompound4.png

    Notice that the equilibrium constant, K, is very large.

    activemethylenecompound5.png


    This page titled Active Methylene Compound 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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