The preparation of a cobalt(IIT) complex with Coen2​ (en = ethylenediamine) units bound with two pyridine nitrogen atoms of two different polymeric chains of poly-(4-vynilpyridine) in trans position was performed. The obtained compound is insoluble in water as well as in the most usual organic solvents, while it has partial solubility in some others, such as dimethylsulfoxide. By elemental analysis it was found that for 12-13 average pyridine nitrogen atoms, one cobalt(III) atom is available