Catalysis of Redox Processes by Nitroxyl Radicals

Nitroxyl mono- and biradicals have been widely used in various physicochemical, biochemical, and biophysical investigations owing to their unique property, stable paramagnetism [1–6]. In addition, nitroxyl radicals (R2NO·) can participate in reactions of reversible one-electron oxidation and reduction yielding relatively stable products, oxopiperidinium cations (R2NO+) and 1-hydroxypiperidines (R2NOH) [2,3].*