A Series of Mixed-Ligand Cu(I) Complexes Comprising Diphosphine-Disulfide Ligands: Effects of Diphosphine Ligands on Luminescent Properties.

Mixed-ligand Cu(I) complexes have attracted attention as alternatives to the noble- and/or rare-metal complexes, because of their remarkable photofunctions. To develop mixed-ligand Cu(I) complexes with rich photofunctions, an investigation of a suitable combination of ligands has captured more and more research interests. Herein, we report the first examples of emissive heteroleptic diphosphine-disulfide Cu(I) complexes combined with diphosphine ligands. The systematic study using a series of diphosphine ligands revealed that large π-conjugated bridging moieties between the two P atoms in the diphosphine ligands result in higher light-emission performance. When the diphosphine ligand was (R)-BINAP ((R)-BINAP = (R)-(+)-2,2'-bis(diphenylphosphino)-1,1'-binaphthyl), the Cu(I) complex had an emission quantum yield (Φem) of 0.13 and a long emission lifetime (τem = 118 µs).

Brilliant reversible luminescent mechanochromism of silver(I) complexes containing o-bis(diphenylphosphino)benzene and phosphinesulfide.

The Ag(I) complex with o-bis(diphenylphosphino)benzene shows reversible interconversion between blue-emitting (1b) and green-emitting (1g) materials on grinding and heating; comparison of the structure of 1b with another green-emitting crystals (2) having the same formula suggests the chromism results from intermolecular interactions between adjacent phenylene rings.