Radical Cations of Sterically Hindered Phenols as Intermediates in Radiation-Induced Electron Transfer Processes

The radical cations of several preferably sterically hindered phenols have been observed through the radiation-induced electron transfer from the phenol (ArOH) to the parent cations of nonpolar solvents (n- and iso-butyl chloride, cyclohexane, freon-113). For p-methoxyphenol and its 2,6-di-tert-butyl-substituted derivative, ArOH•+ has been characterized after radiolysis at 77 K by EPR and optical absorption spectroscopies. Their broad optical absorption bands at λ = 430 and