The photoluminescence (PL) properties of several recently synthesized ligand-stabilized polynuclear gold(I) selenide complexes were investigated. [Au18Se8(dppe)6]Br2 {dppe = bis(diphenylphosphanyl) ethane} (I) is distinguished by the bright-red long-lived PL (phosphorescence) in the solid state, photosensitization of singlet oxygen, 1O2, in solution, and high photostability. The quantum yield of PL, φPL, is (7.5 ± 0.5) × 10-2 for the polycrystalline I at 293 K (determined using an integrating sphere) and increases up to ∼0.8 at 77 K. The quantum yield of 1O2 is 0.17 ± 0.02 in O2-saturated dichloromethane solutions. [Au10Se4(dpppe)4]Br2 {dpppe = bis(diphenylphosphanyl)pentane} (II) shows a broad near-infrared PL at 880 nm in dichloromethane [φPL = (4 ± 1) × 10-3], which is shifted up to ∼1020 nm in the solid II at 77 K (φPL ∼ 3 × 10-3). Although the quantum efficiency of II as a luminophor is quite moderate, it is comparable to that of organic infrared laser dyes such as Styryl-20 and IR26. A particular configuration of the Au10Se4 core appears to be crucial for the near-infrared PL:  the “isomeric” complexes [Au10Se4(dppm)4]Br2 {dppm = bis(diphenylphosphanyl) methane} (III) and [Au10Se4(depe)4]Cl2 {depe = bis(diethylphosphanyl) ethane} (IV) show no significant PL.

The very stable selenium‐bridged gold complexes [Au10Se4(dppm)4]Br2 and [Au18Se8(dppe)6]Cl2 were obtained by the reaction of gold halide–phosphane complexes [(AuX)2(Ph2P(CH2)nPPh2)] (X=halide; n=1, 2) with silylated selenium derivatives. With the help of electrospray/ionization it was possible to promote the cation [Au18Se8(dppe)6]2+ (see structure; m/z 6568 (!)) nearly fragment‐free into the gas phase. dppm=bis(diphenylphosphanyl)methane, dppe=bis(diphenylphosphanyl)ethane.

Dedicated to Professor Achim M¸ller on the occasion of his 65th birthday Many investigations towards synthesis and structural characterization of large metal-rich clusters have been reported over the last few years. Particularly noteworthy are the oxometallates of molybdenum described by M¸ller et al.; only recently Na 48 [H x Mo 368 O 1032 (H 2 O) 240 (SO 4 ) 48 ]¥n 1000 H 2 O (x % 16; n % 1000), the largest known derivative of a heteropolyacid was structurally characterized. [1] Other examples of large cluster complexes are [Pd 145 (CO) x (PEt 3 ) 30 ] (x % 60) made by Dahl et al. [2] and [Ga 84 {N(SiMe 3 ) 2 } 20 Li 6 Br 2 (thf) 20 ] reported by Schnˆckel and Schnepf. [3] The synthesis of the larger Ag±S cluster complexes [Ag 14 S(SPh) 12 (PPh 3 ) 8 ] [4] and [HNEt 3 ] 4 -[Ag 50 S 7 (SC 6 H 4 tBu) 40 ] [5] was recently achieved by Jin et al.Over the last few years one of our major fields of interest was the synthesis of transition-metal clusters containing S, Se, Te, P, As, and Sb as bridging ligands, for example, copperchalcogenide clusters stabilized by tertiary phosphane ligands. [6] Reactions of transition-metal salts with Group 16 silyl derivatives E(SiMe 3 ) 2 or RESiMe 3 (R ¼ alkyl-or aryl-; E ¼ S, Se, Te) allows access to these clusters. [7] Addition of tertiary phosphanes to these reactions prevents the formation of the thermodynamically stable binary phase. [8] Compounds obtained by this route include: [Cu 146 Se 73 -(PPh 3 ) 30 ], [9] [Ag 172 Se 40 (SenBu) 92 (dppp) 4 ] [10] [Ag 38 Te 13 (TetBu) 12 (dppe) 6 ] (dppe ¼ bis(1,2-diphenylphosphanyl)ethane), [11] [Au 18 Se 8 -(dppe) 6 ]Cl 2 [12] , and [Zn 16 Te 13 (TePh) 6 (tmeda) 5 ] [13] (tmeda ¼ tetramethylethylenediamine). Herein we report the synthesis of the Ag±S clusters 1, 2, and 3 containing 120 and 282 heavy atoms, respectively, in the cluster core. ½Ag 70 S 16 ðSPhÞ 34 ðPhCO 2 Þ 4 ðtriphosÞ 4 1 ½Ag 188 S 94 ðPnPr 3 Þ 30 2 ½Ag 188 S 94 ðPnBu 3 Þ 30 3The reaction of a suspension of silver benzoate and triphos [1,1,1-tris{(diphenylphosphanyl)methyl}ethane] with a mixture of S(Ph)SiMe 3 and S(SiMe 3 ) 2 (2:1) at À20 8C in diglyme produces a deep red solution from which small red needles of 1 [Eq. (1)], can be isolated.Reaction of S(SiMe 3 ) 2 with silver trifluoroacetate and PnPr 3 at À40 8C in diglyme initially produces a red solution. After a few hours stirring, the reaction is allowed to warm up to room temperature. The solution becomes dark and black crystals of 2 are formed [Eq. (2)]. Employment of PnBu 3 in an analogous reaction produces black crystals of 3 [Eq. (2)]. Depending on the reaction conditions, 2 is often produced together with black amorphous Ag 2 S. Attempts to recrystallize 2 and 3 from THF or CH 2 Cl 2 failed and produced Ag 2 S as the only isolatable material. The different colors of 1 and 2 (red and black) arise from quantum size effect, which result from the dependency of the band gap on particle size. [14] 2 þSðSiMe3 Þ2 þPnPr3The molecular structures of complexes 1 and 2 in the solidstate were determined by X-ray crysta...

Die Umsetzung von Gold‐Phosphan‐Komplexen [(AuX)(PR3)] (X= Halogen; R = org. Rest) mit Se(SiMe3)2 führt zu neuen chalkogenoverbrückten Goldkomplexen. Durch die Verwendung mehrzähniger Phosphanliganden konnten Clusterkomplexe wie [Au10Se4(dpppe)4]Br2 (1) (dpppe = 1, 5‐Bis (diphenylphosphino)pentan), [Au2Se(dppbe)]∞ (2) (1, 4‐Bis(diphenylphosphino)benzol), [(Au3Se)2(dppbp)3]Cl2 (3) (dppbp = 4, 4′‐Bis(diphenylphosphino)biphenyl) und [Au34Se14(tpep)6(tpepSe)2]Cl6 (4) (tpep = 1, 1, 1‐Tris(diphenylphosphino)ethylphosphan, tpepSe = 1, 1‐Bis‐(di‐phenylphosphinoethyl)‐1‐(diphenylselenophosphinoethyl)phosphan) isoliert und deren Struktur mit Hilfe der Einkristallstruktur‐Analyse bestimmt werden (Strukturdaten s. Abstract).

Professor Kurt Dehnicke zum 70. Geburtstag gewidmet Inhaltsu È bersicht. Zweiza È hnige Phosphanliganden haben sich als sehr effektiv zur Stabilisierung von mehrkernigen chalkogenverbru È ckten Silberclusterkernen erwiesen. Sie treten dabei teilweise als intra-oder intermolekulare Bru È ckenliganden auf. Von den folgenden synthetisierten Clusterverbindungen wurden die Moleku È lstrukturen bestimmt: {[Ag 5 -(TePh) 6 (Ph 2 P(CH 2 ) 2 PPh 3 )](Ph 2 P(CH 2 ) 2 PPh 2 )} ¥ (1), [Ag 18 Te-(TePh) 15 (Ph 2 P(CH 2 ) 3 PPh 2 ) 3 Cl] (2) und [Ag 38 Te 13 (TetBu) 12 -(Ph 2 P(CH 2 ) 2 PPh 2 ) 6 ] (3). Wa È hrend die Verbindungen 2 und 3Moleku È lstrukturen mit isolierten Clusterkernen besitzen, findet man fu È r 1 eine durch Phosphanliganden verbru È ckte polymere Kette.(1: Raumgruppe P2 1 /c (Nr. 14), Z = 4, a = 3518,1(7) pm, b = 2260,6(5) pm, c = 3522,1(7) pm, b = 119,19(3)°; 2: Raumgruppe R3 (Nr. 148), Z = 6, a = b = 3059,4(4) pm, c = 5278,8(9) pm; 3: Raumgruppe Pccn (Nr. 56), Z = 4, a = 3613,0(9) pm, b = 3608,6(7) pm, c = 2153,5 (8) pm) Novel Silver-Telluride Clusters Stabilised with Bidentate Phosphine Ligands: Synthesis and Structure of {[Ag 5 (TePh) 6 (Ph 2 P(CH 2 ) 2 PPh 3 )](Ph 2 P(CH 2 ) 2 PPh 2 )} ¥ , [Ag 18 Te(TePh) 15 (Ph 2 P(CH 2 ) 3 PPh 2 ) 3 Cl], and [Ag 38 Te 13 (TetBu) 12 (Ph 2 P(CH 2 ) 2 PPh 2 ) 3 ] Abstract. Bidentate phosphine ligands have been found effective to stabilise polynuclear cores containing silver and chalcogenide ligands. They can act as intra and intermolecular bridges between the silver centres. The clusters {[Ag 5 (TePh) 6 (Ph 2 P(CH 2 ) 2 PPh 3 )](Ph 2 P(CH 2 ) 2 PPh 2 )} ¥(1), [Ag 18 Te(TePh) 15 (Ph 2 P(CH 2 ) 3 PPh 2 ) 3 Cl] (2), and [Ag 38 Te 13 -(TetBu) 12 (Ph 2 P(CH 2 ) 2 PPh 2 ) 3 ] (3) have been prepared and their molecular structure determined. Compound 2 and 3 are molecular structures with separated cluster cores while 1 forms a polymeric chain bridged by phosphine ligands.(1: space group P2 1 /c (No. 14), Z = 4, a = 3518,1(7) pm, b = 2260,6(5) pm, c = 3522,1(7) pm, b = 119,19(3)°; 2: space group R3 (No. 148), Z = 6, a = b = 3059,4(4) pm, c = 5278,8(9) pm; 3: space group Pccn (No. 56), Z = 4, a = 3613,0(9) pm, b = 3608,6(7) pm, c = 2153,5(8) pm)