A Stable Radical Anion of Quinoxalin-2(1H)-one in Aerial Dioxygen Activation under Wet-Condition

In this report, we describe a highly convenient, non-photochemical and unprecedented method for generating stable radical anions and activating atmospheric dioxygen in wet environments. This activation occurs in aerobic and ambient reaction conditions, specifically in the context of quinoxalin-2(1H)-one oxygenation, with KOtBu. The outcome is the successful demonstration of a straightforward method for synthesizing quinoxaline-2,3-dione. Notably, the crucial role of KOtBu as a single electron transfer (SET) reagent is emphasized, as it initiates dioxygen activation, thereby triggering the oxygenation reaction.