Synthesis, Characterization, and Luminescence Studies of Discrete Polynuclear Gold(I) Sulfido and Selenido Complexes with Intramolecular Aurophilic Contacts

Abstract

The synthesis, characterization, and photophysical and photochemical properties of a family of high-nuclearity gold(I) chalcogenides, specifically, the gold(I) sulfido and selenido complexes containing different bridging diphosphine ligands with nuclearities of ten ([Au10{μ-Ph2PN(R)PPh2}4(μ3-E)4](2+)) and six ([Au6{μ-Ph2PN(R)PPh2}3(μ3-E)2](2+)), are reported. The X-ray crystal structures of the complex cations of Au10 and Au6 are found to be propeller-like structures and distorted cubane structures, respectively, with the presence of short intramolecular gold···gold distances. The complexes show intense green and/or orange phosphorescence upon photoexcitation in the solid state and in solution at ambient and low temperature. The emission properties are found to be strongly dependent on the nuclearities and the chalcogenido ligands, but are rather insensitive to the substituents on the bis(diphenylphosphino)amines. The emissions are tentatively assigned to originate from the excited states derived from the phosphine-centered intraligand (IL) transition or metal-centered (ds/dp) mixed with ligand-to-metal-metal charge transfer (LMMCT) (E→Au) transition. The photochemical properties of the complexes were also studied by transient absorption spectroscopy.

“Host–guest” binding of a luminescent dinuclear Au(i) complex based on cyclic diphosphine with organic substrates as a reason for luminescence tuneability

“…Photostability of Au(I) complexes in solutions is of great importance in the viewpoint of their spectral behavior, since photodegradation is a factor for an instability of Au(I) complexes. 45 NMR spectral data indicate stability of (AuCl) 2 L in DMSO solutions (Fig. S8 in the ESI †).…”

Metal Nanoclusters Stabilized by Selenol Ligands

“…In the structure of Se–Au 10 , eight Au atoms from an irregular, corrugated octagon that is centered by two further Au atoms ( Figure a, top) . Of note, the DPPM ligand in Au 10 Se 2 (DPPM) 4 can be replaced by the Ph 2 P(CH 2 ) 5 PPh 2 or the Ph 2 P(NPh)PPh 2 ligands . Besides, the reaction between (AuBr) 2 DPPE and Se(SiMe 3 ) 2 yields the Au 18 Se 8 (DPPE) 6 complex.…”

Syntheses, structures and theoretical investigations of [Au10S2(PPh2)2(dppma2)4(dppma3)]·[Au6S2(dppma2)2(dppma3)]

“…4(3) to 228.4(3) pm, respectively, and the Au-S-Au angles are between 86.8(1)°a nd 107.2(1)°; deviations from the ideal value of 90°are often observed in gold(I) μ 3 -sulfido complexes. [5][6][7][8]14 As shown in Fig. 1, 1a and 1b interdigitate, reminding of a lock-and-key like arrangement of both subunits.…”

“…E = S, Se; X = H, Me, OMe, F, Cl, Br). 7,8 In this work, we report on further extension of the investigations considering ligands that are based on maleic anhydride. In particular, we used a chlorogold(I) precursor containing the 2,3-bis(diphenylphosphino)maleic anhydride (dppma) ligand, [(AuCl) 2 (dppma)], to form polynuclear gold(I) µ 3 -sulfido clusters.…”