Benzofuroxans electrochemical reduction

The UV PE spectra of furazan and benzofurazan have been recorded and interpreted with the aid of ab initio MO calculations. X-ray photoelectron spectroscopic studies for benzotrifuroxan support the NMR assignment of structure as (15) rather than hexanitrosobenzene. The radical anions of benzofurazan and benzofuroxan, generated by alkali metal or electrochemical reduction have been studied by ESR spectroscopy. 

Electrochemical reduction (see also Section V,D,5) of furoxans produces radical-anions derived from the reduction products (e.g., the benzofurazan radical-anion, from benzofuroxan), as shown by the electron spin resonance (ESR) spectra.138 Benzotrifuroxan (19) gives a radical-anion showing a... 

The electrochemical reduction of a number of furoxan derivatives has been studied polarographically. The products depend on the pH of the medium. Benzofuroxan appears to be reduced first to the dioxime anion and then further to diaminophenazine and o-phenylenediamine.138,433,434 Naphthofuroxan behaves similarly, in that the number of waves which are observed depends on the acidity and that the dioxime is the first product.433 Other electroreduction experiments have been carried out, particularly with bibenzofuroxan sulfone, with a view to the development of a reversible depolarizer for nonaqueous battery systems.435-437 The results of ESR measurements on the electrochemical reduction products of several furoxans are mentioned in Section III,E. 

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