title: A Molybdenum(0) Isocyanide Analogue of Ru(2,2'-Bipyridine)3 (2+) : A Strong Reductant for Photoredox Catalysis.
abstract: We report the first homoleptic Mo(0) complex with bidentate isocyanide ligands, which exhibits metal-to-ligand charge transfer ((3) MLCT) luminescence with quantum yields and lifetimes similar to Ru(bpy)3 (2+) (bpy=2,2'-bipyridine). This Mo(0) complex is a very strong photoreductant, which manifests in its capability to reduce acetophenone with essentially diffusion-limited kinetics as shown by time-resolved laser spectroscopy. The application potential of this complex for photoredox catalysis was demonstrated by the rearrangement of an acyl cyclopropane to a 2,3-dihydrofuran, which is a reaction that requires a reduction potential so negative that even the well-known and strongly reducing Ir(2-phenylpyridine)3 photosensitizer cannot catalyze it. Our study thus provides the proof-of-concept for the use of chelating isocyanides to obtain Mo(0) complexes with long-lived (3) MLCT excited states that are applicable to unusually challenging photoredox chemistry.
authors.affiliation: Department of Chemistry, University of Basel, St. Johanns-Ring 19 and Spitalstrasse 51, 4056, Basel, Switzerland.
authors.forename: Laura A
authors.initials: LA
authors.lastname: Büldt
authors.affiliation: Department of Chemistry, University of Basel, St. Johanns-Ring 19 and Spitalstrasse 51, 4056, Basel, Switzerland.
authors.forename: Xingwei
authors.initials: X
authors.lastname: Guo
authors.affiliation: Department of Chemistry, University of Basel, St. Johanns-Ring 19 and Spitalstrasse 51, 4056, Basel, Switzerland.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Prescimone
authors.affiliation: Department of Chemistry, University of Basel, St. Johanns-Ring 19 and Spitalstrasse 51, 4056, Basel, Switzerland. oliver.wenger@unibas.ch.
authors.forename: Oliver S
authors.identifier: 0000-0002-0739-0553
authors.initials: OS
authors.lastname: Wenger
keywords: electron transfer; isocyanide ligands; luminescence; photocatalysis; photochemistry