I encountered the following equilibrium constant values for the keto-enol interconversions of phenol in Organic Chemistry (Solomons, Fryhle, Snyder, 3rd Edition):
I wonder what could explain the differences (though I'm not sure whether they're significant) between the equilibrium constants of the two keto-enol interconversions wherein in one case the double bond of carbon with the oxygen and the hydrogens are oriented in ortho position and in para position in the other.
Edit: Can this difference concern the medium the reaction is catalyzed in or directive influence of groups? Do explanations for equilibrium constant differences exist for other tautomer interconversions or are such queries quite speculative?