Design and Synthesis of Diphosphine Ligands Bearing an Osmium(II) Bis(terpyridyl) Moiety as a Light-Harvesting Unit: Application to Photocatalytic Production of Dihydrogen

We have designed and prepared novel diphosphine ligands bearing an Os(tpy) 2 2+ moiety as a light-harvesting unit and have found that these diphosphine ligands coordinate to the rhodium atom in a bidentate manner. The rhodium complexes including diphosphine ligands bearing an Os(tpy) 2 2+ moiety have been revealed to work as an effective photocatalyst for the production of dihydrogen.