Ungewöhnlich effiziente strukturdirigierte Phosphoreszenz in Silber(I)‐Clustern, realisiert mit Carba‐closo‐dodecaboranylethinyl‐Liganden

Abstract

Ausgehend von {Ag 2 (12-CC-closo-1-CB 11 H 11 )} n und ausgewählten Pyridinliganden wurden photostabile Ag ICluster synthetisiert, die,m it einer Ausnahme,e ine für Ag IVerbindungen ungewçhnliche Raumtemperaturphosphoreszenzz eigen. Eine besonders intensive Phosphoreszenz wurde für einen verzerrt pentagonal-bipyramidalen Ag

Silver(I) Clusters Stabilized by the Carba‐closo‐dodecaboranylethynyl Ligand with O‐Donor Coligands and Template Ions

“…Compound 2 reveals very weak luminescence, only, and it was not possible to determine the quantum yield. This is a further similarity to [Ag(4‐CF 3 Py) 2 ] 2 [Ag 14 (12‐C≡C‐ closo ‐1‐CB 11 H 11 ) 8 (4‐CF 3 Py) 12 ], which is a weak emitter, also …”

“…The structure of the Ag I 14 cluster in 2 is loosely related to the one of the dianion [Ag 14 (12‐C≡C‐ closo ‐1‐CB 11 H 11 ) 8 (4‐CF 3 Py) 12 ] 2– (4‐CF 3 Py = 4‐CF 3 C 6 H 4 N) that also possesses a central Ag I 10 core. The latter dianion was fully characterized as its [Ag(4‐CF 3 Py) 2 ] + salt, previously . However, while the Ag I 10 cage in [Ag 14 (12‐C≡C‐ closo ‐1‐CB 11 H 11 ) 8 (4‐CF 3 Py) 12 ] 2– is a distorted decahedron that alternatively can be interpreted as two interpenetrating pentagonal bipyramids, the structure of the Ag I 10 unit in 2 is less regular (Figure ).…”

“…Crystallization of {Ag 2 (12‐C≡C‐ closo ‐1‐CB 11 H 11 )} n ( 1 ) from tetrahydrofuran in a dry atmosphere affords single crystals of [Ag 16 (12‐C≡C‐ closo ‐1‐CB 11 H 11 ) 8 (THF) 12 ] · 2THF ( 3 ). Since the crystals of 3 slowly lose THF, they have to be stored under a THF atmosphere.…”

“…More often, the { closo ‐1‐CB 11 } cluster is bonded to a functional group that binds to the metal. Phosphanes, nitriles, N ‐heterocyclic carbenes, and alkynes with carba‐ closo ‐dodecaboranyl groups are recent examples for such derivatives.…”

“…The electronic and structural properties of the {12‐C≡C‐ closo ‐1‐CB 11 H 11 } 2– ligand are decisively determined by the spherical and anionic { closo ‐1‐CB 11 } cage, which is bonded via boron to the C≡C moiety. Unprecedented coordination compounds such as tetrahedral Au I 4 clusters solely stabilized via aurophilic interactions and silver(I) clusters with highly unusual photophysical properties have been observed , . Recently, we have shown that the {12‐C≡C‐ closo ‐1‐CB 11 H 11 } 2– ligand is a strong donor moiety that can actively participate in the formation of luminescent CT states in coinage metal(I) complexes …”