Benzofurazans electrochemical reduction

Benzofurazan, 7-chloro-4-nitro-, 6, 394 as fluorigenic agents, 6, 410, 426 Benzofurazan, 4-chloro-7-sulfo-ammonium salt properties, 6, 426 Benzofurazan, 4-nitro-synthesis, 6, 408 Benzofurazans, 6, 393-426 Beckmann fragmentation, 6, 412 biological activity, 6, 425 bond angles, 6, 396 bond lengths, 6, 396 diazo coupling, 6, 409 dipole moments, 6, 400 electrochemical reduction, 5, 73 electrophilic reactions, 6, 409-410 ESR spectroscopy, 6, 400... 

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... 

Cationic rings are reduced with the uptake of one electron (e.g., electrochemically) to give neutral radicals. Examples of radicals which have been detected by ESR are 373 and 374. Such radicals, e.g., those 376 from benzothiazolium ions, can dimerize (to 377) or undergo further reduction (to 378) in practice, a mixture of the dihydro derivative 378 and the dimer 377 is obtained. Benzofurazan is reduced polarographically in a six-electron reaction to o-phenylenediamine. 

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