PHENAZINE DI-N-OXIDE RADICAL-CATION AND ITS REACTIONS WITH HYDROCARBONS

The absorption spectra of phenazine di-N-oxide radical cation (OPO+.) in dichloromethane were recorded by the spectroelectrochemical method in the range from 300 to 700 nm. The reactions of the electrochemicall y generated OPO+. with para-substituted toluenes, ethylbenzene, and cu mene were studied. Using differential cyclic voltammetry, relative rat e constants of reactions of OPO+. with substrates were determined; the ir correlations with sigma(para)(+) constants of substituents gives rh o = -2.7, which attests to the nonradical character of the reaction of OPO+. with RH. This conclusion is confirmed by the study of the effec t of O-2 on oxidation of ethylbenzene and cumene.