A Highly Soluble Luminescent Decanuclear Gold(I) Complex with a Propeller-Shaped Structure

Abstract

The chemistry of polynuclear d 10 metal systems has attracted numerous studies in the past few decades, and many of them involved the investigation of their structure and their photoluminescent behavior. [1] These properties are often affected by the presence of weak metal ± metal interactions as a result of a relativistic effect that leads to the contraction of the ns orbital of the d 10 metal center. [2] This effect is most prominent for gold and leads to the phenomenon of aurophilicity commonly found in gold complexes, in which aggregation through short sub-van-der-Waals gold ± gold contacts of around 3.05 occurs. [3] Chalcogenides, with their propensity to bridge metal atoms, could serve as ideal candidates for polynuclear metal complex formation. Although chalcogenido copper(i) and silver(i) clusters are known and a number of them have been structurally characterized, most are insoluble or have low solubility in common organic solvents. [4] Examples of soluble polynuclear d 10 metal chalcogenides are scarce, especially those of gold. [5±7] Recently, we reported the isolation of a series of soluble tetranuclear copper(i) and silver(i) chalcogenido complexes with the general formula [M 4 (m-dppm) 4 (m 4 -E)]X 2 (M Cu, Ag; dppm bis(diphenylphosphanyl)methane; E S, Se, Te; X PF 6 , OTf trifluoromethanesulfonate), [8] , as well as the dodecanuclear gold(i) sulfido complex [Au 12 (m-dppm) 6 (m 3 -S) 4 ]-(PF 6 ) 4 . [6] All were structurally characterized and shown to exhibit rich photophysical properties. Structurally related gold(i) complexes with the general formulas [E(AuPPh 3 ) 3 ] (E S, Se, Te) and [E(AuPPh 3 ) 4 ] 2 (E S, Se) were also reported. [7] Here we report the synthesis and the structural characterization of a novel soluble, high-nuclearity luminescent m 3 -sulfidogold(i) complex with bridging diphosphanylamine ligands, namely, [Au 10 (m-PNP) 4 (m 3 -S) 4 ](PF 6 ) 2 (PNP Ph 2 PN(nPr)PPh 2 ).Reaction of H 2 S with a suspension of [Au 2 Cl 2 (PNP)] [9] in ethanol/pyridine followed by metathesis reaction with NH 4 PF 6 in methanol and recrystallization from acetone/ diethyl ether afforded [Au 10 (m-PNP) 4 (m 3 -S) 4 ](PF 6 ) 2 (1) as yellow crystals in 72 % yield. The formulation of 1 was confirmed by elemental analyses, positive FAB and ESI mass spectrometry, 1 H and 31 P NMR spectroscopy, 1 H ± 1 H COSY

Luminescence color switching of supramolecular assemblies of discrete molecular decanuclear gold(I) sulfido complexes

“…Herein, we report the preparation and tunable spectroscopic properties of a series of decanuclear gold(I) (45). The present work demonstrates that polynuclear gold(I) chalcogenides, with the introduction of appropriate functional Significance Polynuclear gold(I) complexes have attracted enormous attention over the past decades owing to their intriguing luminescence behavior and their interesting structural and bonding properties, especially with regard to their propensity to form noncovalent short gold-gold contacts.…”

“…S2), similar to that of related gold(I) chalcogenido complexes (45). Upon photoexcitation, complexes 1-4 in dichloromethane displayed a dual luminescence in the green and orange-red regions (Fig.…”

“…Based on our interests and experience in the study of gold(I) chalcogenido clusters (44)(45)(46)51), it is believed that nanoaggegrates with interesting luminescence properties and morphology could be prepared by the judicious design of the gold(I) chalcogenido clusters. As demonstrated by our previous studies on the aggregation behavior of square-planar platinum(II) complexes (77)(78)(79)(80) where an enhancement of the solubility of the metal complexes via introduction of solubilizing groups on the ligands and the fine control between solvophobicity and solvophilicity of the complexes would have a crucial influence on the factors governing supramolecular assembly and the formation of aggregates (80), introduction of long alkyl chains as solubilizing groups in the gold(I) sulfido clusters may serve as an effective way to enhance the solubility of the gold(I) clusters for the construction of supramolecular assemblies of novel luminescent nanoaggegrates.…”

“…Moreover, while studies on polynuclear gold(I) complexes or clusters are known , less is explored of their hierarchical assembly and nanostructures as well as the influence of intercluster aggregation on the optical properties (34)(35)(36)(37)(38). Among the gold(I) complexes, polynuclear gold(I) chalcogenido complexes represent an important and interesting class (44)(45)(46)(47)(48)(49)(50)(51). While directed supramolecular assembly of discrete Au 12 (52), Au 16 (53), Au 18 (51), and Au 36 (54) metallomacrocycles as well as trinuclear gold (I) columnar stacks (34)(35)(36)(37)(38) have been reported, there have been no corresponding studies on the supramolecular hierarchical assembly of polynuclear gold(I) chalcogenido clusters.…”

Synthesis and characterization of heterobimetallic complexes with pyridyl selenolato ligands. Crystal structure of [{Pt(C5H4N)(SeC5H4N)(dppp)}ZnCl2]

“…Thus, the Lewis basic core {Pt2(µ-E)2} ( E= S, Se) can be combined with Lewis acidic metal complexes to give mixed-metal materials as well as multinuclear homo-platinum complexes [15]. Despite growing interest in the Pt2S2 core as a metallophilic ligand still the heavier analog like Pt2Se2, PtSe2 remain uncharted, even those which have proven better nuclophilic behavior [19,20] and luminescence property [21,22].…”