Reactions of the Radiolytically Generated Hydroxycyclohexadienyl Radical in Aqueous Benzene Systems

The radiolysis of${\rm N}_{2}{\rm O}\text{-saturated}$ aqueous benzene solutions has been investigated by aqueous liquid chromatographic methods. It is shown that phenol, biphenyl and at least five unidentified nonvolatile phenol-like substances with absorption spectra in the region 210-290 nm similar to that of phenol were produced upon the γ-radiolysis of the${\rm N}_{2}{\rm O}\text{-saturated}$ neutral aqueous benzene solution. Several of these products including phenol and biphenyl were primarily produced by postirradiation reactions since the yields of these products increased upon storing the irradiated solutions. It is concluded that hydroxycyclohexadienyl radical produced by the addition of the radiolytically generated hydroxyl radical to benzene was primarily converted to products other than phenol and/or biphenyl. Phenol formation in post irradiation reactions was and biphenyl formation was not acid catalyzed. Phenylphenols were identified among products of postirradiation reactions. The nature and composition of products formed in the pulse and the γ-radiolysis conditions was, as expected, different. The analyses of the γ-irradiation solutions indicated that the number of products and their concentration ratios in the${\rm N}_{2}{\rm O}\text{-saturated}$ aerated and deaerated solutions was different. The product composition of aerated and deaerated systems was also significantly altered due to postirradiation reactions.