共查询到20条相似文献,搜索用时 15 毫秒
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Yuyang Zhu Dr. Cynthia S. Day Lin Zhang Katarina J. Hauser Prof. Amanda C. Jones 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(37):12264-12271
As a result of explorations into the solution chemistry of silver/gold mixtures, a unique diphosphine trimetallic chloronium dication was discovered that incorporates silver–arene chelation and a triangular mixed gold/silver core in the solid state. Notably, it was isolated from a Celite prefiltered solution initially thought to be silver‐free. The crystal structure also incorporates the coordination to silver of one fluorine atom of one SbF6? counterion. The structure was compared to two new, but well‐precedented, phosphine digold chloride cations. DFT calculations supported significant silver–halide and silver–arene interactions in the mixed gold/silver complex and metallophilic interactions in all three complexes. Comparison of computed data revealed that the ωB97X‐D functional, which has a long‐range corrected hybrid with atom–atom dispersion corrections, gave a better fit to the experimental data compared with the PBE0 functional, which has previously failed to capture aurophilic interactions. Preliminary studies support the presence of the mixed gold/silver structure in solution. 相似文献
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Dr. Rafael Gramage‐Doria Joeri Hessels Stefan H. A. M. Leenders Dr. Oliver Tröppner Maximilian Dürr Prof. Dr. Ivana Ivanović‐Burmazović Prof. Dr. Joost N. H. Reek 《Angewandte Chemie (International ed. in English)》2014,53(49):13380-13384
Homogeneous transition‐metal catalysis is a crucial technology for the sustainable preparation of valuable chemicals. The catalyst concentration is usually kept as low as possible, typically at mM or μM levels, and the effect of high catalyst concentration is hardly exploited because of solubility issues and the inherent unfavorable catalyst/substrate ratio. Herein, a self‐assembly strategy is reported which leads to local catalyst concentrations ranging from 0.05 M to 1.1 M , inside well‐defined nanospheres, whilst the overall catalyst concentration in solution remains at the conventional mM levels. We disclose that only at this high concentration, the gold(I) chloride is reactive and shows high selectivity in intramolecular C? O and C? C bond‐forming cyclization reactions. 相似文献
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Yukie Takemura Hiroe Takenaka Takayuki Nakajima Prof. Tomoaki Tanase Prof. 《Angewandte Chemie (International ed. in English)》2009,48(12):2157-2161
A flexible building block : Flexible tetragold(I) chain complexes supported by a new single methylene‐bridged tetraphosphine ligand were synthesized and further transformed into discrete linear octagold(I) {Au8} and cyclic hexagold(I) {Au6} structures by reaction with KI and NaAuCl4, respectively (see picture, Au purple, Cl dark green, PF6 light green, I pink). The tetragold complexes are also luminescent at room temperature.
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Eduardo J. Fernández Dr. Christopher Hardacre Prof. Antonio Laguna Prof. M. Cristina Lagunas Dr. José M. López‐de‐Luzuriaga Dr. Miguel Monge Dr. Manuel Montiel Dr. M. Elena Olmos Dr. Raquel C. Puelles Eva Sánchez‐Forcada 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(25):6222-6233
Metallophilic Au???Ag interactions exist in concentrated solutions as well as in the 2D polymeric solid‐state structure of [AuAg3(C6F5)(CF3CO2)3(CH2PPh3)]n (see picture for the asymmetric unit) according to EXAFS and pulsed‐gradient spin‐echo NMR spectroscopy measurements. Calculations support both the emission assignments and the existence of the metallophilic interactions in solution.
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Dr. Tania Lasanta Prof. Dr. José M. López‐de‐Luzuriaga Dr. Miguel Monge Dr. M. Elena Olmos David Pascual 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(15):4754-4766
Heteronuclear complexes {[Hg(R)2][Au(R′)(PMe3)]2}n (R=R′=C6Cl2F3 ( 3 ); R=R′=C6F5 ( 4 ); R=C6Cl2F3, R′=C6F5 ( 5 ); R=C6F5, R′=C6Cl2F3 ( 6 )) were prepared by the treatment of the corresponding organomercury compounds, [Hg(C6X5)2], with two equivalents of [Au(C6X5)(PMe3)]. Their crystal structures, as determined by using X‐ray diffraction methods, display Au???Hg interactions. Although only compound 4 and 5 show luminescence in the solid state, all of these compounds quench the fluorescence of naphthalene in solution. Solution studies of these derivatives suggest a cooperative effect of the gold(I) center in switching on the quenching capabilities of the [Hg(C6X5)2] synthon with naphthalene. Theoretical studies confirmed the quenching ability of the organomercury species in the presence of gold. 相似文献
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Inside Back Cover: Cluster Linker Approach: Preparation of a Luminescent Porous Framework with NbO Topology by Linking Silver Ions with Gold(I) Clusters (Angew. Chem. Int. Ed. 47/2014) 下载免费PDF全文
Zhen Lei Xiao‐Li Pei Zhan‐Guo Jiang Prof. Dr. Quan‐Ming Wang 《Angewandte Chemie (International ed. in English)》2014,53(47):12971-12971
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Christophe Werlé Corinne Bailly Dr. Lydia Karmazin‐Brelot Xavier‐Frédéric Le Goff Dr. Michel Pfeffer Dr. Jean‐Pierre Djukic 《Angewandte Chemie (International ed. in English)》2014,53(37):9827-9831
Hemichelation is emerging as a new mode of coordination where non‐covalent interactions crucially contribute to the cohesion of electron‐unsaturated organometallic complexes. This study discloses an unprecedented demonstration of this concept to a Group 9 metal, that is, RhI. The syntheses of new 14‐electron RhI complexes were achieved by choosing the anti‐[(η6:η6‐fluorenyl){Cr(CO)3}2] anion as the ambiphilic hemichelating ligand, which was treated with [{Rh(nbd)Cl}2] (nbd=norbornadiene) and [{Rh(CO)2Cl}2]. The new T‐shaped RhI hemichelates were characterized by analytical and structural methods. Investigations using the methods of the DFT and electron‐density topology analysis (NCI region analysis, QTAIM theory) confirmed the closed‐shell, non‐covalent and attractive characters of the interaction between the RhI center and the proximal Cr(CO)3 moiety. This study shows that, by appropriate tuning of the electronic properties of the ambiphilic ligand, truly coordination‐unsaturated RhI complexes can be synthesized in a manageable form. 相似文献
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Cluster Linker Approach: Preparation of a Luminescent Porous Framework with NbO Topology by Linking Silver Ions with Gold(I) Clusters 下载免费PDF全文
Zhen Lei Xiao‐Li Pei Zhan‐Guo Jiang Prof. Dr. Quan‐Ming Wang 《Angewandte Chemie (International ed. in English)》2014,53(47):12771-12775
A cluster‐based luminescent porous metal–organic framework has been constructed through a “cluster linker” approach. The luminescent gold(I) cluster, prefunctionalized with pyrazinyl groups, was used as a cluster linker, similar to an organic linker, to connect silver ions in order to form a 3D framework. 1D channels with 1.1 nm diameter were observed in the framework. The cluster with its intrinsic luminescence was incorporated into a porous framework to give a luminescent bifunctional NbO net. This MOF shows solvatochromic behavior, and the interactions between solvent molecules and silver ions inside the channels account for the changes in absorption and emission spectra. 相似文献
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Glenna So Ming Tong Dr. Steven Chi Fai Kui Dr. Hsiu‐Yi Chao Dr. Nianyong Zhu Dr. Chi‐Ming Che Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(41):10777-10789
The complexes [Au3(dcmp)2][X]3 {dcmp=bis(dicyclohexylphosphinomethyl)cyclohexylphosphine; X=Cl? ( 1 ), ClO4? ( 2 ), OTf? ( 3 ), PF6? ( 4 ), SCN?( 5 )}, [Ag3(dcmp)2][ClO4]3 ( 6 ), and [Ag3(dcmp)2Cl2][ClO4] ( 7 ) were prepared and their structures were determined by X‐ray crystallography. Complexes 2 – 4 display a high‐energy emission band with λmax at 442–452 nm, whereas 1 and 5 display a low‐energy emission with λmax at 558–634 nm in both solid state and in dichloromethane at 298 K. The former is assigned to the 3[5dσ*6pσ] excited state of [Au3(dcmp)2]3+, whereas the latter is attributed to an exciplex formed between the 3[5dσ*6pσ] excited state of [Au3(dcmp)2]3+ and the counterions. In solid state, complex [Ag3(dcmp)2][ClO4]3 ( 6 ) displays an intense emission band at 375 nm with a Stokes shift of ≈7200 cm?1 from the 1[4dσ*→5pσ] absorption band at 295 nm. The 375 nm emission band is assigned to the emission directly from the 3[4dσ*5pσ] excited state of 6 . Density functional theory (DFT) calculations revealed that the absorption and emission energies are inversely proportional to the number of metal ions (n) in polynuclear AuI and AgI linear chain complexes without close metal???anion contacts. The emission energies are extrapolated to be 715 and 446 nm for the infinite linear AuI and AgI chains, respectively, at metal???metal distances of about 2.93–3.02 Å. A QM/MM calculation on the model [Au3(dcmp)2Cl2]+ system, with Au???Cl contacts of 2.90–3.10 Å, gave optimized Au???Au distances of 2.99–3.11 Å in its lowest triplet excited state and the emission energies were calculated to be at approximately 600–690 nm, which are assigned to a three‐coordinate AuI site with its spectroscopic properties affected by AuI???AuI interactions. 相似文献
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Eduardo J. Fernández José M. López-de-Luzuriaga Miguel Monge Elena Olmos Antonio Laguna M. Dolores Villacampa Peter G. Jones 《Journal of Cluster Science》2000,11(1):153-167
The compounds [Au3(S2CNMe2)3{
3-(PPh2)3CH]} (1) and [Au3(S2CNMe2)(-S2CNMe2){
3-(PPh2)3CH}]ClO4 (2) are obtained by reaction of [Au3Cl3{
3-(PPh2)3CH}] with three equivalents of sodium dimethyldithiocarbamate or two equivalents of the same reagent in the presence of excess NaClO4. Reaction of 2 with the group 11 metal complexes [AuCl(tht)], CuCl or [Au(C6F5)(tht)] takes place with displacement of [M(S2CNMe2)]n (M=Cu, Au) and formation of the new complexes [Au3X(-S2CNMe2){
3-(PPh2)3CH}]ClO4 (X=Cl (3), X=C6F5 (4)); further reaction of 3 with [Ag(OClO3)(tht)] (tht=tetrahydrothiophene) affords the dicationic species [Au3(-S2CNMe2){
3-(PPh2)3CH}(tht)](ClO4)2 (5). Treatment of [Au3Cl3{
3-(PPh2)3CH}] with one equivalent of NaS2CNMe2 allows the substitution of only one chlorine atom, giving rise to the complex [Au3Cl2(S2CNMe2){
3-(PPh2)3CH}] (6), in which the dithiocarbamate ligand acts as monodentate rather than bidentate bridging as observed in compounds 3–5. The crystal structures of complexes 1 and 2 have been established by X-ray diffraction studies and show close gold–gold contacts. 相似文献
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Synthesis and Structural Characterization of Magnesium‐Substituted Polystibides [(LMg)4Sb8] 下载免费PDF全文
Dr. Chelladurai Ganesamoorthy Dr. Christoph Wölper Dr. Anton S. Nizovtsev Prof. Dr. Stephan Schulz 《Angewandte Chemie (International ed. in English)》2016,55(13):4204-4209
Redox reactions of [(L1,2Mg)2] and Sb2R4 (R=Me, Et) yielded the first Mg‐substituted realgar‐type Sb8 polystibides [(L1,2Mg)4(μ4,η2:2:2:2‐Sb8)] (L1=HC[C(Me)N(2,4,6‐Me3C6H2)]2, L2=HC[C(Me)N(2,6‐i‐Pr2C6H3)]2). Compounds [(L1,2Mg)2] serve both as reducing agents, initiating the cleavage of the Sb?C bonds, and as stabilizers for the resulting Sb8 polyanion. The polystibides were characterized by NMR and IR spectroscopies, elemental analysis, and X‐ray structure analysis. In addition, results from quantum chemical calculations are presented. 相似文献
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Hexanuclear Gold(I) Phosphide Complexes as Platforms for Multiple Redox‐Active Ferrocenyl Units 下载免费PDF全文
Dr. Terence Kwok‐Ming Lee Dr. Eddie Chung‐Chin Cheng Dr. Nianyong Zhu Prof. Dr. Vivian Wing‐Wah Yam 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(1):304-310
The synthesis, X‐ray crystal structures, electrochemical, and spectroscopic studies of a series of hexanuclear gold(I) μ3‐ferrocenylmethylphosphido complexes stabilized by bridging phosphine ligands, [Au6(P?P)n(Fc‐CH2‐P)2][PF6]2 (n=3, P?P=dppm (bis(diphenylphosphino)methane) ( 1 ), dppe (1,2‐bis(diphenylphosphino)ethane) ( 2 ), dppp (1,3‐bis(diphenylphosphino)propane) ( 3 ), Ph2PN(C3H7)‐PPh2 ( 4 ), Ph2PN(Ph‐CH3‐p)PPh2 ( 5 ), dppf (1,1′‐bis(diphenylphosphino)ferrocene) ( 6 ); n=2, P?P=dpepp (bis(2‐diphenylphosphinoethyl)phenylphosphine) ( 7 )), as platforms for multiple redox‐active ferrocenyl units, are reported. The investigation of the structural changes of the clusters has been probed by introducing different bridging phosphine ligands. This class of gold(I) μ3‐ferrocenylmethylphosphido complexes has been found to exhibit one reversible oxidation couple, suggestive of the absence of electronic communication between the ferrocene units through the Au6P2 cluster core, providing an understanding of the electronic properties of the hexanuclear AuI cluster linkage. The present complexes also serve as an ideal system for the design of multi‐electron reservoir and molecular battery systems. 相似文献