Visible-Light-Promoted Photoredox Syntheses of α,β-Epoxy Ketones from Styrenes and Benzaldehydes under Alkaline Conditions

A range of styrenes and benzaldehydes were smoothly combined to form α,β-epoxy ketones under the synergistic actions of photocatalyst Ru­(bpy)₃Cl₂, <i>tert</i>-butyl hydroperoxide (<i>t</i>-BuOOH), cesium carbonate (Cs₂CO₃), and visible light irradiation. The process likely proceeds through visible-light-enabled photocatalytic generations of acyl radicals as key intermediates.