Green Electrosynthesis of Pyrano[2,3-d]Pyrimidinones at Room Temperature

Electrocatalytic transformation of barbituric acid, aldehyde and malononitrile in ethanol in an undivided cell in the presence of potassium bromide as an electrolyte results in the formation of substituted pyrano[2,3-d]pyrimidinones at room temperature in 65-85% yields. The progress and completeness of electrolysis were monitored by cyclic voltammetry (CV). The voltammograms were recorded with ?Autolab FRA2 Potentiostat-Galvanostat. A three-electrode system was used with a platinum rod as working electrode, a GC electrode as the counter electrode and an Ag/AgCl as the reference electrode. The structure of products was characterized by FT-IR, 1H NMR and 13C NMR spectroscopy. In this electrosynthesis, the first step is electrochemical that follows by chemical reaction. Therefore the proposed mechanism is EC