Electrochemical oxidation of 1,2-Dihydroxypyridazine-3,6-dione in the presence of malononitrile

1,2-Dihydropyridazine-3,6-dione (3,6-dihydroxypyridazine) is a plant growth regulator and used extensively in agriculture as a major commercial herbicide and as suppression of sprouting of vegetable and stored food crops, control of sucker growth on plant, retardation of flowering and prolongation of dormancy period [1]. In previous work, the electrochemical behavior of 1,2-dihydropyridazine-3,6-dione on glassy carbon electrode in aqueous and some organic solvents was investigated. The results indicate that the electrochemically generated pyridazine-3,6-dione is unstable and via oxidative ring cleavage converts to maleic acid [2]. In this work, electrochemical oxidation of 1,2-dihydroxypyridazine-3,6-dione has been studied in the presence of malononitrile in aqueous solution using cyclic voltammetry as a diagnostic technique. The results showed that the electrochemically generated pyridazine-3,6-dione participates in Michael type addition reaction with malononitrile via an ECET mechanism and is converted to the corresponding new dicyanide derivatives. In this work, some new dicyanide derivatives are provided with high yields in aqueous solutions, without toxic reagents and solvents at a carbon electrode in an undivided cell using an environmentally friendly method.