Synthesis, structure, spectra and redox activities of model compounds for methanogenic bacteria
Por:
Pandiyan T.
Publicada:
1 ene 1996
Resumen:
Synthetically accessible benzimidazoles have been synthesized and the benzimidazole ligands were complexed with nickel(II) nitrate. A nickel(II) complex of N,N?-bis(benzimidazole-2-ylethyl)ethylenediamine was crystallized in single-crystal form and the structure was investigated by X-ray crystallography. The structure of the complex is bicapped axial coordinated octahedral. Ni(bbes)2 2+ [bbes = bis(benzimidazole-2-ylethyl)sulfide] exhibits broad low energy bands in electronic spectra and high redox potential in cyclic voltammetry (CV) rather than Ni(enbzim)2+ [enbzim = N,N?-bis(benzimidazol-2-ylethyl)ethylenediamine], where high energy well separated bands were observed in the visible region and a more negative redox potential was detected in CV. Experimental studies show that an increasing amount of ?-orbital interaction with the Ni2+ion, irrespective of chelate ring may favour the higher redox potential. The higher redox potential of methanogenic bacterial [Ni(II)/Ni(I)] than nickel compounds is one of the main factors for the degradation of organic biodegradable compounds and the further transformation to methane. © Springer-Verlag 1996.
Filiaciones:
Pandiyan T.:
Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, 04510 México D.F., Mexico