Air- and Water-Persistent C‑Centered Radical Anion Based on FLP-Type-Activated CO2.

Organic radicals play pivotal roles in chemistry, biology, and materials science. Although typically short-lived and highly reactive, considerable efforts have been devoted to stabilizing open-shell molecules to better understand their properties and expand their applications. Among them, air-persistent organic radicals (APORs) stand out as benchmarks of stability. Herein, we report the first air- and water-persistent radical anion derived from CO2. This species is generated from an FLP-type-activated CO2 adduct comprising an N-heterocyclic carbene (NHC) as the Lewis base and a ditopic perfluorinated diborane as the Lewis acid. Combined experimental and theoretical studies reveal that both thermodynamic and kinetic factors contribute to the remarkable stability of this open-shell system.