The new ligand pyridin-4-yl) quinoline) and the corresponding aqua complex [Ru(Qltpy)(bpy)(OH 2 )](PF 6 ) 2 (1) have been synthesized and characterized by the different spectroscopic methods. This complex shows two pK a values, pK a 1 due to the deprotonation from the protonated N atom located on the quinoline moiety at 3.0 and another pK a 2 at 10.5 due to the deprotonation from aqua ligand. The catalytic activity of the complex 1 towards water oxidation was studied in CF 3 SO 3 H solution (pH % 1) using Ce IV as an oxidant. The free N atom of the substituted quinoline moiety of the complex gets protonated at pH % 1 and acts as an electron withdrawing group instead of electron donating group. Due to the electron withdrawing effect it shows a lower catalytic activity towards chemical water oxidation having turnover number (TON) of 18 (out of 25) and initial turnover frequency (TOF) 0.003 s À1 as compared to the previously reported [Ru II (QCl-tpy)(bpy)(H 2 O)] 2 + complex.[a] J.

The mononuclear [Ru(QCl-tpy)(bpy)(H 2 O)](PF 6 ) 2 was successfully synthesized and characterized by using several spectroscopic techniques (QCl-tpy = 2-4'-(2-chloroquinolin-3-yl)-2,2':6',2''-terpyridine). This complex shows only one pK a value at 10.2, due to the deprotonation from the bonded aqua ligand. This complex was successfully employed as a catalyst for chemical water oxidation in CF 3 SO 3 H solution (pH 1.0) by using Ce IV as an oxidant, shows initial turnover frequency (TOF) of 0.0014 s À1 .The manometry and electrochemical data shows that this complex is a better catalyst having turnover number (TON) 19 (out of 25) and overpotential of 600 mV. As compared to the parent Ru(tpy)(bpy)(H 2 O)](PF 6 ) 2 a higher catalytic effect was observed by complex 1, which is expected due to the cause of electronic effect dominating towards electron donating behavior.[a] J.

Dehydrogenation of formic acid is an emerging domain in the sustainable energy system. In this study a half-sandwich [Ru(η 6benzene)(hdm)]BF 4 [Ru-hdm] complex (hdm = hydroxydi (pyridine-2-yl)methanolate) has been synthesized and characterized through various spectroscopic techniques. The [Ruhdm] has been used to dehydrogenate formic acid in simple water using sodium formate (HCOONa) as a base has also been depicted in this study. The [Ru-hdm] complex is a descent catalyst towards dehydrogenation of formic acid into carbon dioxide and hydrogen in 1 : 1 ratio, which has been detected by gas chromatography.

The [Ru(η6-benzene)(L)Cl] (complex 1, L = 2-methylquinolin-8-olate and complex 2, L = quinolin-8-olate) complexes were synthesised and employed for the dehydrogenation of the formic acid (FA) in the presence of...

Water splitting is an emerging domain in the sustainable energy system. In this study a half‐sandwich [Ru(η6‐benzene)(hdm)]BF4 [Ru‐hdm] complex (hdm=hydroxydi(pyridine‐2‐yl)methanolate) has been synthesized and characterized through various spectroscopic techniques. The complex [Ru‐hdm] has been employed to investigate the activity towards electrochemical and chemical water oxidation. Efficient generation of O2 through chemical and electrochemical water oxidation (98 % Faradaic efficiency) in deionized water was observed. The formation of insoluble particles of [RuVI=O] and [RuIV=O] species in the reaction mixture and a coating over the surface of the silicone rubber septum has been noticed. The kinetics of chemical water oxidation reveals the 1st order dependency on CAN and catalyst concentration.