Skip to main content
Chemistry LibreTexts

Thermodynamic Enolate

  • Page ID
    40596
  • \( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \) \( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)\(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\) \(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\)\(\newcommand{\AA}{\unicode[.8,0]{x212B}}\)

    Treatment of an unsymmetrical ketone with a base could result in two enolate ions. The more stable enolate ion is called the thermodynamic enolate and the faster forming one the kinetic enolate.

    eg: Ketone 1, upon treatment with a base, could yield the enolate ions 2 and 3.

    thermodynamicenolate.png

    2 is more stable than 3 because the carbon-carbon double bond in 2b, the more stable resonance form of 2, is more stable than that in 3b, the more stable resonance form of 3. Thus, 2 is the thermodynamic enolate.

    3 forms faster than 2 because in 1 the H1 atoms are more accessible to the base than the H2 atom, due to the fact that the H1 atoms are sterically less hindered than the H2 atom. Thus, 3 is the kinetic enolate.

    see also thermodynamic control, kinetic control


    This page titled Thermodynamic Enolate 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.

    • Was this article helpful?