The oxidation reaction by the coordinated nitrosyl group in [Ru(NO)(NO
2)(M-tap)2](ClO4)2 (1) (M-tap = m-tolylazopyridine) is described. Comp
lex 1 brings about the oxidative coupling of N,N-dimethylaniline (DMA)
to tetramethylbenzidine (TMB) and the oxidation of RuCl2(bpy) 2 (bpy
= 2,2'-bipyridine) to [RUCI2(bpy)2]+. These redox reactions have been
studied voltametrically and the results have been analysed in terms of
the electrophilicity of the coordinated NO' in 1.