Polychlorinated alkylation annulation of N-arylacrylamide under electrochemical conditions

Abstract

A novel and unprecedented method for the polychlorinated alkylation annulation of N-arylacrylamide has been developed under electrochemical conditions with diazo salt as the mediator at the cathode reduction and CH₂Cl₂ as the substrate and solvent. Remarkably, it is benzene free radicals generated from the diazo salt under reductive electrolytic conditions that induce the hydrogen transfer of CH₂Cl₂, resulting in the formation of polychloromethyl radicals, which were transferred into the bulk phase solution and then reacted with the N-arylacrylamide substrate. This electrochemical diazo-salt-mediated protocol provides a broad range of functional tolerance and affords good yields for polychloromethyl indolone derivatives under ambient conditions at room temperature in a simple undivided cell.