Electrochemical synthesis of substituted 2-amino-4H-chromen-3-carbonitrides based on cross-conjugated dienone derivatives of cyclohexane and malononitrile

The relevance of research in the field of chemistry of compounds of a number of 2-aminochromen(pyran)-3-carbonitrile is due to their practical significance and numerous transformation possibilities. Over the past two decades, there has been a dynamic development of the electrochemical synthesis of compounds of this series, which is determined by the possibility of eliminating expensive or toxic reagents, conducting reactions at normal temperatures and pressure in electrolyzers of a fairly simple design and other advantages. Based on the efficiency and environmental friendliness of this method, we have for the first time synthesized 2-aminotetrahydro-4H-chromene-3-carbonitriles based on available cross-conjugated dienone derivatives of cyclohexane series and malononitrile under electrolysis conditions (platinum cathode, graphite anode, KBr electrolyte, 80% EtOH). The control over the course of the reaction and the electrochemical behavior of all components has been carried out using cyclic voltammetry. The analysis of the voltammograms made it possible to establish the direct activation of the methylene component at the cathode with the formation of the anion -CH(CN)2. A comparison of the electrochemical synthesis of chromencarbonitriles with the chemical one indicates a significant advantage of electrosynthesis due to the exclusion of a toxic organic catalyst, reduction of reaction time with good yields of products, as well as the possibility of monitoring reactions using cyclic voltammetry, dispersion of products.