The enol contents and equilibrium constants of the ketcrenol tautomerism of ethyl acetoaretate were determined in various solvents using UV spectroscopy. It was found that in supercritical CO2 the enol content decreases dramatically in the presence of 0.047mol.L-1 ethanol.In liquid cyclohexane, however, the effect of the same amount of ethanol on enol content is not detectable. The strong cosolvent effect in SC CO2 results from the clustering of the cosolvent around the solute.
