title: Closer to photosystem II: a Co4O4 cubane catalyst with flexible ligand architecture.
abstract: We introduce the novel Co4O4 complex [Co(II)4(hmp)4(μ-OAc)2(μ2-OAc)2(H2O)2] (1) (hmp = 2-(hydroxymethyl)pyridine) as the first Co(II)-based cubane water oxidation catalyst. Monodentate acetate and aqua ligands lend the flexible environment of 1 closest resemblance to photosystem II among its tetranuclear mimics to date. Visible-light-driven catalytic activity of 1 increases with pH value through aqua ligand deprotonation. The Co(II) core combines robustness and stability with flexibility through a new type of water-oxidation mechanism via mobile ligands.
authors.affiliation: Department of Chemistry, University of Zurich , Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
authors.forename: Fabio
authors.initials: F
authors.lastname: Evangelisti
authors.forename: Robin
authors.initials: R
authors.lastname: Güttinger
authors.forename: René
authors.initials: R
authors.lastname: Moré
authors.forename: Sandra
authors.initials: S
authors.lastname: Luber
authors.forename: Greta R
authors.initials: GR
authors.lastname: Patzke
mesh_terms: D002384:Catalysis; D008024:Ligands; D008958:Models, Molecular; D045332:Photosystem II Protein Complex / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D056928:X-Ray Absorption Spectroscopy
chemical_list: D008024:Ligands; D045332:Photosystem II Protein Complex