Synthesis and Characterization of a Series of New Luminescent NHC‐Coordinated Au^I–Ag^I Tetra‐ and Polymetallic Complexes Containing Benzoate‐Bridged Ag₂ Dimers

Abstract

The reaction of [Au(CH3impy)2]PF6 (2), with substituted silver benzoate salts bearing different halide substituents produced a series of new mixed‐metal species having two different structural motifs. One structural motif contains discrete tetrametallic Ag2Au2 diamond cores, whereas the other motif contains the same tetrametallic diamond core interconnected by benzoate‐bridged silver dimers to form polymers. All the complexes are substitution‐inert and stable both in the solid state as well as in solution. We also report the synthesis of oxidative addition products of [Au(CH3impy)2]PF6, which were also obtained during our attempts to oxidize the above‐mentioned multimetallic assembly with bromine and iodine. Compounds 3–7 are intensely luminescent in frozen acetonitrile solution, but surprisingly no luminescence is observed at room temperature. All the complexes were completely characterized by 1H, 13C NMR, electronic absorption, emission spectroscopy, elemental analysis and X‐ray crystallography. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Beyond catalysis: N-heterocyclic carbene complexes as components for medicinal, luminescent, and functional materials applications

“…Introduction of a bidentate coordinating carboxylate anion rather than using non-coordinating BF 4 -allows for the incorporation of a second Ag + ion, thus expanding the Ag:Au ratio from 1:1 in 29 to 2:1. 38 The tetrametallic molecular square 32 has been synthesized 370 by Hahn and coworkers via reaction of nickelocene with the benzdiimidazolium salt 30 and subsequent coupling of the bimetallic Ni 2 (dicarbene) complex 31 with 4,4'-bipyridine as connecting ligand (Scheme 3). 39 Crystallographic analysis of the remarkably air-and water-stable molecular square 375 indicates an essentially coplanar arrangement of the nickel atoms and virtually identical Ni ... Ni separation along the dicarbene and the bipyridine axes.…”

124I-Radiolabeling of a Au(III)-NHC Complex for in Vivo Biodistribution Studies

“…Bond distances and angles of both compounds (see Table S2) are comparable to those measured for structurally related Au(III) complexes. [1][2][3] CCDC 1989306-1989307 contain the supplementary crystallographic data for this paper.…”

“…In combination with in vitro analyses, this radiolabeling strategy provides direct evidence of the importance of Au(III)-to-Au(I) reduction for achieving full anticancer activity.In modern medicine Au compounds are recognized for their beneficial activity against rheumatoid arthritis, being the clinically-approved auranofin the most representative drug of this type. [1][2][3] Nevertheless, the discovery that auranofin has also potent anticancer effects, [4,5]…”

“…In modern medicine Au compounds are recognized for their beneficial activity against rheumatoid arthritis, being the clinically-approved auranofin the most representative drug of this type. [1][2][3] Nevertheless, the discovery that auranofin has also potent anticancer effects, [4,5]…”

Trifluoromethylpyridine-SubstitutedN-Heterocyclic Carbenes Related to Natural Products: Synthesis, Structure, and Potential Antitumor Activity of some Corresponding Gold(I), Rhodium(I), and Iridium(I) Complexes

“…EI-MS: 535.0/537.0 (M + ), 500.1/502.1 (M + -Cl). ESI-MS: 500.18 (100), 501.11(30), 501.98(40).Chloro(g 4 -1,5-cyclooctadiene){[1,3-bis[2-(3-chloro-5-(trifluoromethyl)pyridin-2-yl)ethyl]-1H-imidazolin-2(3H)-ylidene)}iridium(I) (13). A mixture of 1,3-bis{2-[3-chloro-5-(trifluoromethyl)pyridin-2-yl]ethyl}-1H-imidazol-3-iumchloride (3; 52 mg, 0.1 mmol) and silver(I) oxide (14 mg, 0.06 mmol) in dry CH 2 Cl 2 (10 ml) was stirred for 24 h at r.t. in the absence of light.…”