Synthesis and characterization of New Mononuclear Ru (II) Polypyridine Complexes with Catalytic Activity

PEYROT, ANALÍA M.; ZELAYA, MARIA P; ALBORÉS, PABLO; FAGALDE, FLORENCIA

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY

WILEY-V C H VERLAG GMBH

Lugar: Weinheim; Año: 2023

1434-1948

In this work we report the synthesis and physicochemical characterization of new chloroand aqua mononuclear Ru (II) complexes of formula [Ru(LLL)(dpp)Cl]PF6 and[Ru(LLL)(dpp)OH2](PF6)2 (with LLL= tpy =2,2’:6’,2’’-terpyridine; tptz=2,4,6-tris(2-pyridyl)-1,3,5-triazine and dpp=2,3-bis(2-pyridil)pyrazine). For complex [Ru(tptz)(dpp)Cl]PF6 wasdetermined the complete structure by X-ray diffraction. Catalytic studies of aquacomplexes revealed that they are active against the water oxidation reaction at pH=1using cerium ammonium nitrate (CAN) as sacrificial oxidant. Also, we were able toestablish reaction mechanism and rate constants of each stage of the catalytic cycle,turnover frequency (TOF) and turnover number (TON). The experimental TON value forthe aqua complexes was very close to theoretical value of 7.5, indicating a high degreeof recovery. DFT and TD-DFT calculations of complexes were consistent withexperimental results and allowed the complete assignment of its UV–Visible bands, andredox states.