| Abstract
| - α-Tocopherol (α-TOH) can be electrochemically oxidized in CH3CN containing Bu4NPF6 in achemically reversible two-electron/one-proton (ECE) process to form the phenoxonium cation (α-TO+) thatis stable for at least several hours at 243 K. In the presence of up to ∼1% CF3SO3H, α-TO+ exists inequilibrium with the α-tocopherol cation radical (α-TOH+•), whereas at concentrations between ∼1−3%CF3SO3H the electrochemical oxidation of α-TOH occurs by close to one-electron to form α-TOH+•. α-TOH+•can be further oxidized in a one-electron process to form the α-tocopherol dication (α-TOH2+). The identityand stability of the phenolic cationic compounds were determined by a combination of electrochemical(cyclic voltammetry and controlled potential electrolysis) and in situ spectroscopic (UV−vis−NIR, FTIR,EPR, and NMR) analysis.
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