Role of Keto-Enol Tautomerism in the Polarographical Reduction of Some Carbonyl Compounds

Abstract

During some polarographical investigations of certain α-aminoketones¹ and on the elimination of Mannich bases² experimentàl data were gathered, which can be explained by the occurrence of keto-enol transformation. Though considerable attention has been paid to the mechanism of polarographical reduction of carbonyl compounds³, no experimental evidence has been adduced for the participation of the keto-enol tautomerism in the reduction of the carbon-oxygen bond. This follows from the fact that, in most cases examined, the keto form is the predominating form, and in buffered solutions used, establishment of keto-enol tautomeric equilibrium is fast. However, the decrease of the limiting current of some keto acids has recently been interpreted⁴ as being influenced by the keto-enol equilibrium in addition to hydration.