Structural evolution of the Ru-bms complex to the real water oxidation catalyst of Ru-bda: the bite angle matters

Abstract

The bite angle matters: Opening up the O–Ru–O angle of Ru complexes enables water oxidation catalysis.

Strategic factors to design the next generation of molecular water oxidation catalysts: Lesson learned from ruthenium complexes

“…[125,126] Such type of decomposition is also reported in other molecular complexes which are reinvestigated [126,127] or they have been reported for the first time with different types of a molecular catalyst such as Ni [128,129], Mn [130], and Co [128,131]. The investigation of different Ru based WOCs [97,98] together with the similar structures of WOCs which are stable [116,132,133] versus unstable [39,99,128] ones, guide us that the most possible source of CO2 release during O2 gas detection comes from the oxidation of methylene groups in ligand backbone. [127,134] Arguably, we suggest a rational modification by replacing hydrogen atoms in the methylene groups in the ligand backbone with methyl groups (Figure 20b).…”

Coordination-Adaptive Molecular Platform for Catalytic Water Oxidation

“…By introducing a methylene group to catalyst 4, the O−Ru−O angle of catalyst 18 is reduced to 84°, approaching the ideal octahedral configuration. 56 Although sulfonate has a weak coordinating ability, its nondistorted conformation makes ligand exchange challenging. Additionally, due to the nonoxidatively rugged nature of the methylene group, various other active species evolve during the turnover, with Ru-bda being one of them.…”

“…Here, we would like to emphasize the impact of changes in coordination angle and coordination atom type on catalysis. By introducing a methylene group to catalyst 4 , the O–Ru–O angle of catalyst 18 is reduced to 84°, approaching the ideal octahedral configuration . Although sulfonate has a weak coordinating ability, its nondistorted conformation makes ligand exchange challenging.…”

Efficient Electrochemical Water Oxidation Mediated by Pyridylpyrrole-Carboxylate Ruthenium Complexes

“…Since the “blue dimer” of WOCs was first reported, numerous transition metal complexes based on Fe, Co, Ni, Mn, Cu, Ru, etc., with various ligands have been widely explored . Among them, Ru-based WOCs with various ligands, including polypyridine and its analogues, carboxylatopyridine, organo-phosphonato, and polyoxometalate, have been explored most extensively.…”