Electrocatalytic Synthesis of Spirooxindole-Chromene Derivatives in Ethanol/DMSO Media using a Fe-Mn-O Composite as an Efficient Working Electrode

An efficient and sustainable method was developed for electrocatalytic multicomponent synthesis of spirooxindole-chromene derivatives via a green one-pot, three component condensations of cyclic-1,3-diones, malononitrile and isatins inside an undivided cell where potassium bromide was applied as electrolyte in ethanol/DMSO (95/5 v/v) media, and a practical Fe-Mn-O composite was used as cathode electrode. The presented electrosynthesis approach proved to be reliable and cost-effective for the synthesis of target compounds in 83-91% yields. In this method, we highlight the utility of electrosynthesis method for the preparation of diverse spirooxindole-chromen derivatives that can be a breakthrough for production of vital drugs.