title: A supramolecular ruthenium macrocycle with high catalytic activity for water oxidation that mechanistically mimics photosystem II.
abstract: Mimicking the ingenuity of nature and exploiting the billions of years over which natural selection has developed numerous effective biochemical conversions is one of the most successful strategies in a chemist's toolbox. However, an inability to replicate the elegance and efficiency of the oxygen-evolving complex of photosystem II (OEC-PSII) in its oxidation of water into O2 is a significant bottleneck in the development of a closed-loop sustainable energy cycle. Here, we present an artificial metallosupramolecular macrocycle that gathers three Ru(bda) centres (bda = 2,2'-bipyridine-6,6'-dicarboxylic acid) that catalyses water oxidation. The macrocyclic architecture accelerates the rate of water oxidation via a water nucleophilic attack mechanism, similar to the mechanism exhibited by OEC-PSII, and reaches remarkable catalytic turnover frequencies >100 s(-1). Photo-driven water oxidation yields outstanding activity, even in the nM concentration regime, with a turnover number of >1,255 and turnover frequency of >13.1 s(-1).
authors.affiliation: Universität Würzburg, Institut für Organische Chemie and Center for Nanosystems Chemistry, Am Hubland, 97074 Würzburg, Germany.
authors.forename: Marcus
authors.initials: M
authors.lastname: Schulze
authors.affiliation: Universität Würzburg, Institut für Organische Chemie and Center for Nanosystems Chemistry, Am Hubland, 97074 Würzburg, Germany.
authors.forename: Valentin
authors.initials: V
authors.lastname: Kunz
authors.affiliation: Universität Würzburg, Institut für Organische Chemie and Center for Nanosystems Chemistry, Am Hubland, 97074 Würzburg, Germany.
authors.forename: Peter D
authors.initials: PD
authors.lastname: Frischmann
authors.affiliation: Universität Würzburg, Institut für Organische Chemie and Center for Nanosystems Chemistry, Am Hubland, 97074 Würzburg, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Würthner
mesh_terms: D002384:Catalysis; D047028:Macrocyclic Compounds / Q000737:chemistry; D008667:Metalloproteins / Q000737:chemistry; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D045332:Photosystem II Protein Complex / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D047028:Macrocyclic Compounds; D008667:Metalloproteins; D045332:Photosystem II Protein Complex; D014867:Water; D012428:Ruthenium; D010100:Oxygen