Electrochemical reduction of 1,2,4,6-substituted pyridinium cations

Electrochemical reduction of dodecylpyridinium bromide in aprotic solvents: Mechanistic studies

“…The same effect was observed for the reduction of 1-methylpyridinium ion in acetonitrile 26 . Volke et al 28 studied the substituted pyridinium cations by the phenyl groups in the positions 2, 4 and 6 in dimethylformamide, acetonitrile and dimethylsulfoxide solvents. An overall two electron reduction of substituted pyridinium cation was observed instead of the dimerization process.…”

“…Only few works reported on the reduction of pyridinium cations in organic solvents [25][26][27][28] . Santhanam and Elving 25 studied the reduction properties of 1-substituted 3-nicotinamides in acetonitrile and DMSO.…”

“Organic Aqua Regia”—Powerful Liquids for Dissolving Noble Metals

“…The pyridinium structure is also reflected in the cyclic voltammogram of the gold/organicus liquor regius solution in acetonitrile, where the reduction peak potential at À1.28 V (see Figure S21 in the Supporting Information) in the cathodic scan falls in the range of the reduction potentials of pyridinium compounds. [28] Dimers and trimers of 4-chloropyridine and their derivatives are present in the mass spectra of GTP-RT (see Figures S10 and S11 in the Supporting Information) and the precipitate from the longstanding Au/SOCl 2 /py solution (see Figures S22 and S23 in the Supporting Information). We postulate that 4-chloropyridine might form as an intermediate and Au III catalyzes the oligomerization of 4-chloropyridine.…”

The reductive deposition of quaternary pyridinium corrosion inhibitor multilayers on glassy carbon electrodes

“…Others (3-5) have proposed a series of possible reaction routes for the reduction of nicotinamide under varying pH conditions. Also, a similar reduction mechanism to that in Scheme 1 for analogous substituted pyridinium compounds, but in aprotic solvents, has been suggested (18,21). In addition, it has been reported that dialkylcarbamoylpyridinium could be reduced to form 1,4-dihydropyridine in an aqueous solution (22).…”

“…For example, when two of these species react together, a dimer (Scheme 2a) could be formed if steric hindrance is not a factor (21). Each dimer would then undergo a two-electron reduction process, not involving protons.…”