Artículos de revistas
Electrochemical reduction of 2-nitroimidazole in aprotic medium: Influence of its dissociation equilibrium on the reduction mechanism
Fecha
2006-10-25Registro en:
ELECTROCHIMICA ACTA 52(2):511-518
0013-4686
Autor
Squella Serrano, Juan
Campero, A.
Maraver, J.
Carbajo, J.
Institución
Resumen
The electrochemical reduction of 2-nitroimidazole in a non-aqueous medium using cyclic voltammetry (CV) at a mercury electrode was carried out.
The 2-nitroimidazole derivative in DMF + 0.1 M tetra(n-butyl)ammonium hexafluorophosphate (TBAHFP6) resulted in the following dissociation equilibrium:
HNRNO2 reversible arrow -NRNO, + H+
The neutral species (HNRNO2) and the corresponding conjugate base (-NRNO2) are characterized by UV absorption bands at 328 and 370 nm, respectively.
The voltammograms of 2-nitroimidazole produced two well-defined signals, which were determined by the above dissociation equilibrium. The first reduction peak was caused by the reduction of the neutral species according to the following overall mechanism:
5HNRNO(2) + 4e(-) -> 4(-)NRNO(2) + HNRNHOH + H2O
The second quasi-reversible couple was caused by the reduction of the conjugate base according to the following equation:
-NRNO2 + e(-) -> NRNO2 center dot-