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E,Z Convention

  • Page ID
    40285
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    E,Z Convention is a method used to specify relative configuration at carbon atoms in alkene groups. According to E,Z convention, if the pair of carbon atoms in an alkene group could exist in two relative configurations, one is designated using the label E and the other the label Z.

    eg:

    EZconvention1.png

    To determine whether an alkene group is E or Z, use the following two-step procedure.

    Step 1:
    Assign priority numbers to the two ligands on each carbon atom in the alkene group. (See R,S convention for the procedure.)

    eg. 1:

    EZconvention2.png

    eg. 2:

    EZconvention3.png

    Step 2:

    EZconvention4a.png

    eg. 1:

    EZconvention4.png

    eg. 2:

    EZconvention5.png


    This page titled E,Z Convention 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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