An efficient synthetic protocol for the selenylated cyclic isoureas was developed using electrochemical activation of diselenides. This sustainable approach permitted transition metal and chemical oxidant-free difunctionalization of olefins and overall access to distinct 1,2,3 triheterofunctionalized carbon skeletons. Excellent functional group tolerance was noticed, allowing the synthesis of a series of cyclic isourea derivatives. In addition, an acid-triggered skeletal isomerization facilitated the synthesis of cyclic urea derivatives from the corresponding cyclic isoureas. Mechanistic investigations, along with voltammetric studies, enabled the postulation of the reaction mechanism.