Isocyanid‐Komplexe von Cr⁰, Mo⁰ und W⁰ als Leuchtstoffe und Photosensibilisatoren mit langlebigen angeregten Zuständen

Abstract

Abstractd6‐Metallkomplexe der Gruppe 6 mit Arylisocyanid‐Liganden sind aus in der Erde reichlich vorhandenen Elementen aufgebaute Alternativen zu photoaktiven Komplexen edler Metalle wie RuII, ReI, OsII oder IrIII. Einige dieser Komplexe haben langlebige angeregte 3MLCT‐Zustände, die Lumineszenz mit guten Quantenausbeuten mit Lebensdauern im Bereich von Nano‐ bis Mikrosekunden vereinbaren und überdies stark reduzierend sind. Kürzlich erfolgte Studien zeigten, dass Cr0‐, Mo0‐ und W0‐Arylisocyanide großes Anwendungspotential in Leuchtvorrichtungen, in der Photoredoxkatalyse und in Farbstoff‐sensibilisierten Solarzellen haben.

Luminescent complexes made from chelating isocyanide ligands and earth-abundant metals

“…Building on a few papers published more than 40 years ago, 5 and inspired by recent reports on W(0) complexes with monodentate isocyanide ligands, 6 we synthesized and explored a new family of Cr(0) and Mo(0) complexes with chelating diisocyanide ligands. 7 Isocyanide groups are needed to stablize the low oxidation states of these metals, 8 and a meta-terphenyl backbone was suitable for accessing a relatively rigid bidentate chelator. (With few exceptions, , and thus our complex is a considerably stronger excited-state reductant than Ir(2phenylpyridine) 3 (E * ox = -1.7 V vs. SCE), which is widely used for photoredox catalysis.…”

“…studies of chelating diisocyanides had focused on more flexible and other types of ligand backbones).10 Homoleptic Cr(0) and Mo(0) tris(diisocyanide) complexes are readily obtained with our ligands, and they are luminescent in fluid solution at room temperature(Figure 1). Molecular structures of d 6 metal complexes along with some key photophysical and electrochemical properties 7,. 11 (λem = emission band maximum; τ( 3 MLCT) =3 MLCT lifetime in de-aerated solvents at room temperature; J.…”

Chromium complexes for luminescence, solar cells, photoredox catalysis, upconversion, and phototriggered NO release

“…3 MLCT luminescence from Mo(0) and W(0) was readily detectable at room temperature, and Cr(0) emission was observed at 77 K. 9 Then, these complexes seemed forgotten for nearly 40 years, until new reports on Mo(0) and W(0) appeared. 45 – 49 We were curious whether it would be possible to obtain a Cr(0) complex that luminesces at room temperature in solution, particularly in view of the recent interest in isoelectronic Fe( ii ) complexes in the greater context of dye-sensitized solar cells. 50 – 56 …”

Intensely Photoluminescent Diamidophosphines of the Alkaline‐Earth Metals, Aluminum, and Zinc

“…lanthanide-doped inorganic supports), molecular luminescent complexes have gathered increasing attention over the last few decades as they can be used in new optical devices and organic light emitting diodes (OLEDs), which have significant industrial application. [4] Ap rominent and widely used example of am ain-group fluorophore is Alq 3 (tris (8-hydroxyquinolinato)aluminum) and its derivatives. [3] Thus,t he development of photoactive compounds with non-toxic and earthabundant metals is aw orthwhile challenge in synthetic chemistry.…”

“…[3] Thus,t he development of photoactive compounds with non-toxic and earthabundant metals is aw orthwhile challenge in synthetic chemistry. [4] Ap rominent and widely used example of am ain-group fluorophore is Alq 3 (tris (8-hydroxyquinolinato)aluminum) and its derivatives. [5] Given our interest in metal complexes with multifunctional donor sites,w e intended to use al igand with ah ard amido moiety and as oft phosphine functionality and became aware of ap hosphine-functionalized diamine ligand, N,N-bis(2-(diphenylphosphino)phenyl)ethane-1,2-diamine (PNHNHP), which was reported by Thomas et al in 2011.…”