The mono-bipyridine bis carbonyl complex [Ru(bpy)(CO)(2)Cl-2] exists in two stereoisomeric forms having a trans(Cl)/cis(CO) (1) and cis(Cl)/cis(CO) (2) configuration. In previous work we reported that only the trans(Cl)/cis(CO) isomer 1 leads by a two-electron reduction to the formation of [Ru(bpy)(CO)(2)](n) polymeric film on an electrode surface. This initial statement was overstated, as both isomers allowed the build up of polymers. A detailed comparison of the electropolymerization of both isomers is reported here, as well as the reduction into dimers of parent stereoisomer [Ru(bpy)(CO)(2)(C(O)OMe)Cl] complexes 3 and 4 obtained as side products during the synthesis of 1 and 2.