Electronic Structures and Photoredox Chemistry of Tungsten(0) Arylisocyanides

Abstract

complexes are one-photon visible and two-photon NIR photocatalysts for challenging reductive transformations.

Reversible Photoinduced Ligand Substitution in a Luminescent Chromium(0) Complex

“…According to the abovementioned early study of [Cr­(CNPh) 6 ], additional excited-state distortion of the Cr–CN–Ph bond angles can take place upon MLCT excitation, which can then promote the photodissociation of arylisocyanide units. During the revision process of this paper, a study on isostructural Mo 0 and W 0 complexes with the same L tri ligand as used herein appeared, following our previous works on Mo 0 complexes with chelating isocyanides, − , and work on W 0 isocyanides by the Gray/Winkler team. − [Mo­(L tri ) 2 ] and [W­(L tri ) 2 ] were not reported to undergo photoinduced ligand dissociation, in line with the general trend that second- and third-row transition metal complexes are less substitution-labile than those incorporating first-row transition metals.…”

“…Early work performed several decades ago demonstrated that (monodentate) arylisocyanide ligands stabilize chromium in its zerovalent oxidation state and can lead to electronic structures resembling those of well-known isoelectronic Ru II polypyridines. , Closely related W 0 arylisocyanide complexes were found to be strongly luminescent and photoredox active, − and this encouraged us to develop chelating arylisocyanide ligands, which led to Mo 0 , − Mn I , and Cr 0 complexes featuring 3 MLCT luminescence similar to Ru II polypyridines. − Until now, our main focus has been on bidentate ligands, and while we have reported examples of meridionally coordinating tridentate arylisocyanides, , a facially coordinating tridentate arylisocyanide ligand has not been considered by us yet …”