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

Photosubstitution processes in ruthenium amines of the typetrans‐[Ru(NH3)4LL ′]+2 where L are nitrogenous heterocyclic ligands, pyridine (py), isonicotinamide (isn), 4 ‐acetylpyridine (4‐acpy) and 4‐picoline (4‐pic) and the 1,2‐bis(4‐pyridyl)ethane (bpa) ligand, lead to the substitution of nitrogenous ligands by water molecules, however, this change is dependent on the wavelength used. The characteristic of the binder is also another factor to be consi dered since the process of labilization did not occur for all ligands, isn, and 4‐acpy, which gives these complexes photochemical stability and therefore it is possible to classify them as not reactive. AbstractPhotochemical reactions of ruthenium (II) complexes of type trans ‐[Ru(NH3)4LL']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 f or any of the studied complexes. The stud...

Source: Photochemistry and Photobiology - July 31, 2019 Category: Science Authors: Wagner Batista Santos, Kelly Aparecida Encarna ção Amorim, Anderson Dourado Galvão, Fabricio Tarso Moraes, Dario Batista Fortaleza, Luiz Alfredo Pavanin Tags: Research Article Source Type: research