High Oxidation State Iridium Mono-μ-oxo Dimers Related to Water Oxidation Catalysis

• DOI: 10.1021/jacs.6b07716
• Publication Date: 2016-11-15T20:29:57Z
• Authors: Liam S. Sharningh...; Shashi Bhushan Sinha; Dimitar Y. Shopov; Bonnie Choi; Brandon Q. Mercado; Xavier Roy; David Balcells; Gary W. Brudvig; Robert H. Crabtree
• Keywords: Oxidation state; Catalytic Oxidation

The highly active iridium "blue solution" chemical and electrochemical water oxidation catalyst obtained from Cp*IrL(OH) precursors (L = 2-pyridyl-2-propanoate) has been difficult to characterize as no crystal structure can be because of the multiplicity geometrical isomers present. Other data suggest complete loss Cp* ligand formation a LIr-O-IrL unit. We have now developed route series well-defined Ir(IV,IV) mono-μ-oxo dimers, containing closely related L2Ir-O-IrL2 Unlike catalyst, these model compounds are separable by silica gel chromatography readily form single crystals. report three stereoisomers with formula ClL2Ir-O-IrL2Cl, which fully characterized, including X-ray crystallography, compared solution". To best our knowledge, species represent first examples structurally characterized dinuclear μ-oxo without metal-carbon bonds.