Voltammetry and Electron Paramagnetic Resonance Spectra of Halonitrobenzene Anion Radicals.

Revisiting the electrochemical formation, stability and structure of radical and biradical anionic structures in dinitrobenzenes

“…This stabilization may promote bond break at substituent-aromatic ring positions, such as bromine and iodine [16,17], or simple proton dissociation of phenol or carboxylic acid derivatives [18]. Reduction of dinitroaromatic compounds, similarly to the mononitroaromatic ones, are usually also followed by chemical reaction steps [19,20].…”

Variable-Temperature Microelectrode Voltammetry: Application to Diffusion Coefficients and Electrode Reaction Mechanisms

“…Second, we describe application of this technique in the determination of activation parameters for the halide bond cleavage of o -bromonitrobenzene and 9-chloroanthracene. Both species undergo rapid halide bond cleavage via a two-electron transfer process probably via an ECE-type process. − …”

Steric effects in the decomposition of halogenated nitrobenzene anion radicals

“…It is presumed that the existence of only one distinct spectrum for 2,5-dimethylhydroquinone at low temperatures is due to the presence of the trans form only. 2 We may therefore speculate that it is the rotation of the hydroxyl groups at higher temperatures which cause the observed effects. The interesting point is, however, that for an "in-phase modulation" of the methyl and ring protons, both hydroxyl groups are required to rotate in an instantaneously equivalent manbeen successfully reduced to their corresponding anions in aprotic solvents.1 Although many of these radicals are sufficiently stable to permit recording of their electron spin resonance (esr) spectra, a group of halogen-substituted nitroaromatic radicals constitutes a notable exception.…”