Are there any databases with rate constants for keto-enol tautomerism in small molecules? I'm looking for rate constants if possible.

  • $\begingroup$ They're equilibrium processes so a rate constant isn't really meaningful $\endgroup$
    – NotEvans.
    Jan 4 '17 at 20:07
  • $\begingroup$ I'm asking if there is some kind of reference where I could obtain kinetic data of this type. It is useful for what I am trying to do. $\endgroup$
    – XBB
    Jan 4 '17 at 21:23
  • $\begingroup$ My point is that almost any carbonyl will exist to some extent in its enol form. You can't really measure a rate because no sooner as it's made, it's equilibrated. It's not a chemical reaction that you can 'start' and then 'quench' once it's done. Perhaps you can edit your post with more details/an example of what you're looking for $\endgroup$
    – NotEvans.
    Jan 4 '17 at 21:56
  • $\begingroup$ I'm interested in the times for intramolecular proton exchange in small molecules. I understand what you are saying regarding tautomerization being an equilibrium reaction $\endgroup$
    – XBB
    Jan 4 '17 at 22:05
  • $\begingroup$ You could use standard perturbation (relaxation) methods such as (small) temperature or pressure jump to study such reactions, for example $\ce{H2O<=>H^+ + OH^-}$ Searching for the technique may be a way to find data. $\endgroup$
    – porphyrin
    Jan 10 '17 at 15:27

This is not a database, and I don't know about how small molecules you are looking for, I found that article on Jacs Kinetics and thermodynamics of keto-enol tautomerism of simple carbonyl compounds: an approach based on a kinetic study of halogenation at low halogen concentrations

If you can access the file it will be better for you, if not I let you some matrix of values. I hope it can help ! I give you them in the same the order of the publication.

I added some other publication at the end.

tautomerism constant

Tautomerism bis

tautomerism ter


Tautomerization of 2-Acetylcyclohexanone. 1. Characterization of Keto−Enol/Enolate Equilibria and Reaction Rates in Water

Kinetic studies of keto-enol and other tautomeric equilibria by flash photolysis (a lot of constants in this one)


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