Spectroscopic detection and kinetic analysis of short-lived aromatic amine cation radicals using an electron transfer stopped-flow method

Novel trends of electrochemical oxidation of amino-substituted triphenylamine derivatives

“…The electro-oxidation of TPA was similar to the anodic oxidation of tertiary aromatic amines, such as N,N 0 -dimethylaniline, where tetramethylbenzidine formation was observed due to the dimerization of the N,N 0 -dimethylaniline cation radical [14]. Recently, kinetic analyses of these short-lived cation radicals have been carried out using ultramicroelectrode voltammetry [15], rapid-scan cyclic voltammetry [16] and electron transfer stopped-flow methods [17].…”

Electrochemical and Electron Transfer Behavior of o-Chloranil with the Presence of Mg2+ in Acetonitrile

“…For the stopped-flow measurements, a rapid-scan stopped-flow spectroscopic system, RSP-601 (Unisoku Co. Ltd., Hirakata, Japan), was used [14].…”

“…As a supporting electrolyte for the electrochemical measurements, tetrabutylammonium hexafluorophosphate (TBAPF 6 , Fluka, puriss, electrochemical grade) was used as received. For the stopped-flow measurements to evaluate the electron-transfer reactions, the AN solution of tris(p-bromophenyl)amine cation radical (TBPA* ) was prepared electrochemically, whose method was previously described in detail [14]. 6 .…”

Analytical Aspects of Aromatic Amines

“…In another study, where 4-toluidine was added to the collected sample to avoid fast destruction of the PAA (Section III.A.1), results were much higher: 1a (423), 1b (240), 1c (166), 8a (32) and 9a (21), 2-(8.2) and 4-aminobiphenyl (7a, 3.6), 2-fluorenylamine (10b, 3.4), 1-pyrenamine (13, 1.3), 3-fluoranthenamine (14, 1.2) and 6-chrysylamine (15, 0.6). Alkaline tobaccos produced in France and Germany had even larger PAA yields 34 .…”

“…This has the additional advantage over the pulse-electrolysis stopped-flow (PESF) method 239 for generating the free radicals 130a-d that the reaction is homogeneous, allowing direct observation of the effect of the precursors on the electron transfer processes. The ETSF method was applied to kinetic measurements of the free radical dimerization of 130b-d 240 . …”