Radical cations of 1,4-dialkoxybenzenes and alkyl 1,4-dialkoxybenzenes generated through one-electron oxidation by perfluorodiacyl peroxides

Radical cations of 1,4-dialkoxybenzenes 1 and 2 and alkyl 1,4-dialkoxybenzenes 3–9 generated in oxidation of the parent donors by perfluorodi[1-(2-fluorosulfonyl)ethoxy]propionyl peroxide 10 at −40°C and pentafluorobenzoyl peroxide 11 at 15°C were observed by ESR. Radical cation 6 ^+˙, generated in other oxidation systems, i.e., Ce(SO₄)₂/THF, NH₄/OAc and (NH₄)₂S₂O₈/HOAc, has also been investigated. Based on ESR observation and products analysis, an electron-transfer mechanism of the oxidation reaction is proposed and the influencing factors on hyperfine splitting constants of the radical cations are discussed.