Photochemical Properties of trans-[Ru(NH3 )4 (bpa)(L)]2+ (L = py, isn, 4-acpy or 4-pic).

Photochemical reactions of ruthenium (II) complexes of type trans-[Ru(NH3 )4 LL']2+ , where L is a nitrogenous heterocyclic ligand, pyridine (py), isonicotinamide (isn), 4-acetylpyridine (4-acpy) or 4-picoline (4-pic), and L´ is a 1,2-bis(4-pyridyl)ethane (bpa) ligand, were studied with the purpose of evaluating the ligand exchange when, in solution, the complexes are irradiated at the wavelengths of 365, 436, 480 and 519 nm. The study revealed that at lower wavelengths, a labilization process is observed for py and 4-pic ligands, even at low quantum yields, indicating the dependence of the photolabeling process on the wavelength. The study also reveals that for the filters of greater wavelength, the processes of photolabilization do not occur for any of the studied complexes. The study also shows that there are no photolization processes for the complexes obtained with the isn and 4-acpy ligands, and it is therefore possible to classify them as nonreactive.