70326-66-8Relevant articles and documents
Chemical and Electrochemical Reduction of ortho-Nitroanilides. A Combined Chemical, Polarographic and EPR Study
Alberti, Angelo,Carloni, Patricia,Greci, Lucedio,Stipa, Pierluigi,Andruzzi, Romano,et al.
, p. 1019 - 1023 (2007/10/02)
The acetyl and benzoyl o-nitroanilines 1a and 1b and the acetyl and benzoyl o-nitrodiphenylamines 1c and 1d have been reduced chemically (t-BuOK/DMSO) and electrochemically inside the cavity of an EPR spectrometer.For all compounds the EPR signal of the radical anions could be recorded and interpreted.In DMSO the radical anions 1c(1-) and 1d(1-) evolved to the phenazine radical anion within 1 h.The polarographic study showed that the four compounds are reduced in two different steps, the first being monoelectronic and reversible, as demonstrated by cyclic voltammetric experiments.Compounds 1a-d were reduced with Fe/AcOH to the benzimidazoles 5a-d.The catalytic reduction of 1a gave the hydroxy-2-methylbenzimidazole 7a together with the azoxy derivative 6a.The macroscale electrolysis of 1c and 1d may be regarded as a convenient synthetic method of preparing benzimidazoles 5c and 5d, while the catalytic reduction may be considered the best route to benzimidazole N-oxides 4c and 4d.
