The electrochemical oxidation of 2,5-diethoxy-4-morpholinoaniline has been studied in the presence of thiobarbituric acid by the use of experimental and calculation methods. Cyclic voltammetry, controlled-potential coulometry and density functional theory (DFT) were used in this study. By the use of the cyclic voltammetry, the best condition of synthesis was obtained, and controlled-potential coulometry was performed under this condition. The results indicated that the produced p-benzoquinonediimine is unstable, and it was hydrolyzed in the experimental condition. It was found that the produced p-quinoneimine from oxidation/hydrolysis of 2,5-diethoxy-4-morpholinoaniline reacts with the thiobarbituric acid as a nucleophile and via an ECCCEC mechanism converts to the product. Also, computational calculations were used to analyze oxidation peaks in voltammetry. DFT, BP86 level of theory and 6-31G(p,d) basis set, was used to obtain the theoretical results.
