REACTIONS OF HYDRAZOBENZENE AND TETRANITROMETHANE WITH NITROXYL RADICALS

The values of isotropic HFS constants a(N) were obtained for nitroxyl radicals (NR) of the piperidine series in hexane and water. The interr elation between rate constants for NR reduction and oxidation reaction s, isotropic HFS constants a(N), inductive constants sigma'' of the pi peridine substituents, and electrochemical characteristics of NR were found. The dependence of the rate constants for the reduction of NR by hydrazobenzene (HB) and its oxidation by tetranitromethane (TNM) upon the Hammett type inductive constants sigma(EPR), obtained using HFS c onstants a(N) as the basis, was analyzed. The solvent effect on the re duction and oxidation reaction rate constants, the kinetic isotopic ef fect of the reduction reaction for a number of NR-HB systems. and alte rnative reaction mechanisms are considered.