title: Mechanistic studies on the water-oxidizing reaction of homogeneous manganese-based catalysts: isolation and characterization of a suggested catalytic intermediate.
abstract: The synthesis, isolation, and characterization of two high-valent manganese dimers with isomeric ligands are reported. The complexes are synthesized and crystallized from solutions of low-valent precursors exposed to tert-butyl hydroperoxide. The crystal structures display centrosymmetric complexes consisting of Mn(2)(IV,IV)(μ-O)(2) cores, with one ligand coordinating to each manganese. The ligands coordinate with the diaminoethane backbone, the carboxylate, and one of the two pyridines, while the second pyridine is noncoordinating. The activity of these complexes, under water oxidation conditions, is discussed in light of a proposed mechanism for water oxidation, in which this type of complexes have been suggested as a key intermediate.
authors.affiliation: Department of Photochemistry and Molecular Science, Uppsala University, 75120 Uppsala, Sweden.
authors.forename: Gustav
authors.initials: G
authors.lastname: Berggren
authors.forename: Anders
authors.initials: A
authors.lastname: Thapper
authors.forename: Ping
authors.initials: P
authors.lastname: Huang
authors.forename: Lars
authors.initials: L
authors.lastname: Eriksson
authors.forename: Stenbjörn
authors.initials: S
authors.lastname: Styring
authors.forename: Magnus F
authors.initials: MF
authors.lastname: Anderlund