Mechanism of Three-Carbon Tautomerism

Abstract

WITH the object of throwing light on the mechanism of three-carbon tautomerism, we have studied the equilibration of vinylacetic and crotonic acids in the presence of 1.05 mols of sodium hydroxide in dilute heavy water at 100° C. As a check, we have also examined the behaviour of butyric acid under the same conditions. The isotopic ratio in both the recovered solvent and the water obtained by combustion of the residual sodium salts has been determined by a flotation method accurate to one part per million of density; the necessary purifications were carried out without loss of water, thus avoiding the possibility of isotopic fractionation.