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Zaitsev’s Rule

  • Page ID
    42721
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    Zaitsev’s or Saytzev’s (anglicized spelling) rule is an empirical rule used to predict regioselectivity of 1,2-elimination reactions occurring via E1 mechanism or via E2 mechanism. It states that in a regioselective E1 or E2 reaction the major product is the more stable alkene, i.e., the alkene with the more highly substituted double bond.

    eg:

    zaitsevsrule.png

    E1 reaction always follow Zaitsev’s rule; with E2 reactions, there are exceptions (see antiperiplanar).

    see also Hofmann rule


    This page titled Zaitsev’s Rule 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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