- Novel gold(I)- and gold(III)-N-heterocyclic carbene complexes: Synthesis and evaluation of their anticancer properties
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A novel Au(III)-N-heterocyclic carbene organometallic complex supported by two N-heterocyclic carbene (NHC) ligands was synthesized from Au(SMe 2)Cl and 1-methyl-2-pyridin-2-yl-2H-imidazo[1,5-a]pyridin-4-ylium hexafluorophosphate via a Ag intermediate. X-ray crystallography revealed the first example of a square planar geometry adopted by a Au(III) species stabilized by two NHCs and two chloride ligands. The aforementioned Au(I)- and Au(III)-NHC complexes were found to be more potent than cisplatin against the HCT 116, HepG2, A549, and MCF7 cell lines.
- Rana, Bidyut Kumar,Nandy, Abhishek,Bertolasi, Valerio,Bielawski, Christopher W.,Das Saha, Krishna,Dinda, Joydev
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- DISSOLUTION OF METALLIC GOLD IN DMSO-RX SYSTEMS. THE CONCEPT OF A DONOR-ACCEPTOR ELECTRON TRANSFER SYSTEM
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The complexing of gold during dissolution of gold powder in donor-acceptor organic and aqueous-organic Au0-DMSO-RX systems (where R = H or Bu, and X = Cl or Br) was studied.Ten complexes were produced, and their compositions and IR spectra in the 4000-200 cm-1 range were determined.The data obtained were interpreted in terms of the concept of donor-acceptor electron transfer systems. Keywords: metal, gold, dissolution, organic media, DMSO, RX, gold complexes, production, donor-acceptor electron tranfer (DAET) systems, concept.
- Nifontova, G. A.,Lavrent'ev, I. P.
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- Synthesis, Characterization, and in vitro Cytotoxicity of Gold(I) Complexes of 2-(Diphenylphosphanyl)ethylamine and Dithiocarbamates
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Gold(I) complexes of 2-(diphenylphosphanyl)ethylamine or (2-aminoethyl)diphenylphosphine (AEP), and dithiocaarbamates (R2NCS2) were prepared by the reaction of these ligands with (CH3)2S-AuCl in dichloromethane.
- Sulaiman, Adam A. A.,Altaf, Muhammad,Isab, Anvarhusein A.,Alawad, Abdullah,Altuwaijri, Saleh,Ahmad, Saeed
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- A synchronous nucleation and passivation strategy for controllable synthesis of Au36(PA)24: unveiling the formation process and the role of Au22(PA)18 intermediate
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Despite the recent progress on controllable synthesis of alkynyl-protected Au nanoclusters, the effective synthetic means are very limited and the cluster formation process still remains puzzling. Here, we develop a novel synchronous nucleation and passivation strategy to fabricate Au36(PA)24 (PA=phenylacetylenyl) nanoclusters with high yield. In Au36(PA)24 formation process, Au22(PA)18 as key intermediate was identified. Meanwhile, Au22(PA)18 can be synthesized under a low amount of reductant, and by employing more reductants, Au22(PA)18 can turn into Au36(PA)24 eventually. Moreover, the structure evolution from Au22(PA)18 to Au36(PA)24 is proposed, where four Au13 cuboctahedra can yield one Au28 kernel. Finally, the ratiocination is verified by the good accordance between the predicted intermediate/product ratio and the experimental value. This study not only offers a novel synthetic strategy, but also sheds light on understanding the structural evolution process of alkynyl-protected Au nanoclusters at atomic level.
- Ma, Xiaoshuang,Ma, Guanyu,Qin, Lubing,Chen, Guangxu,Chen, Shaowei,Tang, Zhenghua
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- Electropolymerization of Metal Clusters Establishing a Versatile Platform for Enhanced Catalysis Performance
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Atomically precise metal clusters are attractive as highly efficient catalysts, but suffer from continuous efficiency deactivation in the catalytic process. Here, we report the development of an efficient strategy that enhances catalytic performance by electropolymerization (EP) of metal clusters into hybrid materials. Based on carbazole ligand protection, three polymerized metal-cluster hybrid materials, namely Poly-Cu14cba, Poly-Cu6Au6cbz and Poly-Cu6Ag4cbz, were prepared. Compared with isolated metal clusters, metal clusters immobilizing on a biscarbazole network after EP significantly improved their electron-transfer ability and long-term recyclability, resulting in higher catalytic performance. As a proof-of-concept, Poly-Cu14cba was evaluated as an electrocatalyst for reducing nitrate (NO3?) to ammonia (NH3), which exhibited ≈4-fold NH3 yield rate and ≈2-fold Faraday efficiency enhancement compared to that of Cu14cba with good durability. Similarly, Poly-Cu6Au6cbz showed 10 times higher photocatalytic efficiency towards chemical warfare simulants degradation than the cluster counterpart.
- Cai, Jinmeng,Gong, Chun-Hua,Han, Zhen,Li, Si,Li, Yao,Mak, Thomas C. W.,Wang, Qian-You,Wang, Shan,Wang, Yi-Man,Zang, Shuang-Quan
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supporting information
(2022/01/20)
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- Synthesis of L-Au(I)-CF2H Complexes and Their Application as Transmetalation Shuttles to the Difluoromethylation of Aryl Iodides
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We describe herein two alternative protocols to efficiently prepare difluoromethylgold(I) complexes bearing ancillary ligands with different electronic and steric properties. LAu-OX (X = H andt-Bu) species, formed in the presence of base, have been identified as intermediate complexes involved in these transformations. The application of these compounds as “CF2H transmetalation shuttles” from gold to palladium has been demonstrated in a Pd-catalyzed difluoromethylation reaction of aryl iodides, in which the Au-to-Pd transfer of “CF2H” is feasible under stoichiometric conditions. These findings will pave the way for catalytic manifolds in gold chemistry.
- García-Domínguez, Patricia
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supporting information
p. 2923 - 2928
(2021/09/07)
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- Metal cage coordination compound and preparation method thereof, and catalyst
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The invention relates to a metal cage coordination compound and a preparation method thereof, and a catalyst. The metal cage coordination compound of the invention is prepared by assembling gold trichloride and a triphenylphosphine cage ligand composed of dynamic imine via a coordination bond; and the triphenylphosphine cage ligand contains a plurality of imine bonds and is thus soluble in many common organic solvents (such as dichloromethane) and not soluble in methanol or n-hexane. The above metal cage coordination compound is used as a catalyst for participation in an organic reaction, andcan function as a homogeneous catalyst during a reaction; and after the reaction, the metal cage coordination compound can be precipitated by adding methanol or n-hexane and then recycled through recovery via filtration or other manners, so production cost is lowered.
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Paragraph 0080; 0082; 0084
(2019/11/04)
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- Balancing Bulkiness in Gold(I) Phosphino-triazole Catalysis
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The syntheses of a series of 1-phenyl-5-phosphino 1,2,3-triazoles are disclosed, within which, the phosphorus atom (at the 5-position of a triazole) is appended by one, two or three triazole motifs, and the valency of the phosphorus(III) atom is completed by two, one or zero ancillary (phenyl or cyclohexyl) groups respectively. This series of phosphines was compared with tricyclohexylphosphine and triphenylphosphine to study the effect of increasing the number of triazoles appended to the central phosphorus atom from zero to three triazoles. Gold(I) chloride complexes of the synthesised ligands were prepared and analysed by techniques including single-crystal X-ray diffraction structure determination. Gold(I) complexes were also prepared from 1-(2,6-dimethoxy)-phenyl-5-dicyclohexyl-phosphino 1,2,3-triazole and 1-(2,6-dimethoxy)-phenyl-5-diphenyl-phosphino 1,2,3-triazole ligands. The crystal structures thus obtained were examined using the SambVca (2.0) web tool and percentage buried volumes determined. The effectiveness of these gold(I) chloride complexes to serve as precatalysts for alkyne hydration were assessed. Furthermore, the regioselectivity of hydration of but-1-yne-1,4-diyldibenzene was probed.
- Zhao, Yiming,Wakeling, Matthew G.,Meloni, Fernanda,Sum, Tze Jing,van Nguyen, Huy,Buckley, Benjamin R.,Davies, Paul W.,Fossey, John S.
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supporting information
p. 5540 - 5548
(2019/08/07)
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- Mechanism of Photoredox-Initiated C-C and C-N Bond Formation by Arylation of IPrAu(I)-CF3 and IPrAu(I)-Succinimide
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Herein, we report on the photoredox-initiated gold-mediated C(sp2)-CF3 and C(sp2)-N coupling reactions. By adopting gold as a platform for probing metallaphotoredox catalysis, we demonstrate that cationic gold(III) complexes are the key intermediates of the C-C and C-N coupling reactions. The high-valent gold(III) intermediates are accessed by virtue of photoredox catalysis through a radical chain process. In addition, the bond-forming step of the coupling reactions is the reductive elimination from cationic gold(III) intermediates, which is supported by isolation and crystallographic characterization of key Au(III) intermediates.
- Kim, Suhong,Toste, F. Dean
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supporting information
p. 4308 - 4315
(2019/01/25)
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- A Gold Carbene Manifold to Prepare Fused γ-Lactams by Oxidative Cyclisation of Ynamides
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Gold-catalysed oxidative cyclisation reactions of ynamides offer great promise in γ-lactam synthesis but are limited by preferential over-oxidation to form α-keto imides. Evaluating the factors that might limit N-cyclisation pathways led to effective gold-catalysed conditions that allow access to different fused γ-lactams on changing the ynamide N-substituent and accommodate previously incompatible substitution patterns. New and efficient methods for the synthesis of functionalised 3-aryl indoles and cyclohepta[c]pyrrol-1-one derivatives are presented. These conditions illustrate the complementarity of gold catalysis to other metals.
- Sánchez-Cantalejo, Fernando,Priest, Joshua D.,Davies, Paul W.
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supporting information
p. 17215 - 17219
(2018/11/10)
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- New heterobimetallic Au(i)-Pt(ii) polyynes achieving a good trade-off between transparency and optical power limiting performance
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Two series of new heterobimetallic Au(i)-Pt(ii) polyynes have been easily synthesized by cross-coupling under mild conditions. The absorption profiles of these two series of Au(i)-Pt(ii) polyynes are quite similar. However, the Au(i)-Pt(ii) polyynes with a 1,4-bis(diphenylphosphino)benzene ligand show stronger triplet (T1) emission and superior optical power limiting (OPL) performance than the corresponding Au(i)-Pt(ii) polyynes with a 1,3-bis(diphenylphosphino)propane ligand. Hence, the 1,4-bis(diphenylphosphino)benzene ligand is more effective than the 1,3-bis(diphenylphosphino)propane ligand for optimizing the transparency and OPL ability of OPL materials. When compared with the corresponding homometallic Pt(ii) polyynes, these heterobimetallic Au(i)-Pt(ii) polyynes display a blue shift in their absorption spectra, showing better transparency in the visible-light region. Besides, these heterobimetallic Au(i)-Pt(ii) polyynes show stronger OPL ability than their corresponding homometallic Pt(ii) polyynes as well as the state-of-the-art OPL material C60, demonstrating their enormous application potential in the nonlinear optics field. In brief, the introduction of Au(i) precursors with tetrahedral diphosphine ligands into the backbone of Pt(ii) polyynes can simultaneously achieve enhanced transparency and high OPL ability for OPL materials, providing a new strategy to optimize OPL materials.
- Tian, Zhuanzhuan,Yang, Xiaolong,Liu, Boao,Zhong, Daokun,Zhou, Guijiang,Wong, Wai-Yeung
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supporting information
p. 11416 - 11426
(2018/11/20)
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- Diastereoselective synthesis, structure and reactivity studies of ferrocenyloxazoline gold(i) and gold(II) complexes
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In the last few decades, gold complexes have demonstrated huge potential for soft Lewis acid catalysis. Despite the intensive research on Au complexes and planar chiral metallacycles, enantiopure ferrocenylgold complexes have-surprisingly-not been reported until the studies presented in this article. Herein, we report the asymmetric synthesis of planar chiral ferrocenyl Au(i) complexes. These dinuclear species form helically chiral ten-membered (NCCCAu)2 rings stabilized by aurophilic interactions. In supramolecular solid state structures, linear, zigzag or helical Au(i) wires with regular Au?Au separations were observed. The dissolved dinuclear entities could be oxidized by Au(i) to unique ferrocenyl Au(ii) complexes featuring short Au(ii)-Au(ii) bonds, while the ferrocene core remained intact. However, our initial studies revealed the issue of configurational lability of the ferrocenyl Au(ii) complexes in terms of the element of planar chirality in the presence of the gold source, (Me2S)AuCl. This was successfully addressed by a systematic study implementing permanent σ-donor ortho-protecting groups such as methyl and trimethylsilyl, which impede an epimerization event. Oxidation of the dinuclear Au(i) complexes was also accomplished by oxidative addition reactions with halogenated solvents, preferably CHCl3. Additional reactivity studies revealed that dinuclear Au(ii) dihalide complexes are also formed with reactive alkylhalides such as iodomethane, benzylbromide and benzyliodide. Interestingly, the whole spectral range of colors (violet, blue, green, yellow, and red) is covered by the title complexes depending on the Au oxidation state and the anionic ligands in the Au(ii) complexes. This appears to be quite unusual for ferrocenes, which typically adopt orange to red colors in a non-oxidized state.
- Holz, Julia,Ayerbe García, Marta,Frey, Wolfgang,Krupp, Felix,Peters, René
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p. 3880 - 3905
(2018/03/21)
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- Gold nanoparticles on wool in a comparative study with molecular gold catalysts
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The catalytic activity of gold chloride nanoparticles is compared to the activity of two molecular gold(I) chloride phosphine complexes for the addition of methanol to 3-hexyne. The phosphines are triphenylphosphine and the bispidinone related bulky 6,8-bis-(4-dimethylamino-phenyl)-3-methyl-9-oxo-7- phenyl-3-aza-7-phospha-bicyclo[3.3.1]nonan-1,5-dicarboxylic acid dimethyl ester. Use of the bulky ligand made the addition reaction selective towards the enol product, meaning that no addition of methanol or water to alkenes, which were produced during the reaction, occurred. In contrast, use of triphenylphosphine gold(I) chloride resulted in the synthesis of a variety of products. The phosphines decomposed during reaction leading to the formation of gold nanoparticles, which were found to be catalytically inactive. Artificially produced gold nanoparticles also proved to be inactive. In contrast, gold chloride nanoparticles deposited on wool were active comparable to the gold phosphine-containing catalysts tested previously. Overall activities observed were low compared to results from the literature suggesting that the operating conditions chosen could be optimised.
- Borrmann, Thomas,Lim, Teck Hock,Cope, Hannah,Lucas, Kerstin,Lorden, Michael
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- Intermolecular mono-and dihydroamination of activated alkenes using a recoverable gold catalyst
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A combination of gold chloride organometallic complex and a silver salt was used to catalyze intermolecular hydroamination of activated alkenes, i.e aza-Michael reactions. The gold-catalyzed reactions of activated alkenes with nitrogen substrates were investigated and found to afford various mono-and dihydroamination products, the latter being rare and original. After flash chromatography, gold NHC catalyst could be recovered as a gold hydroxide NHC complex. When combined with a silver salt, the gold complex lead again to an active hydroamination catalyst.
- Medina, Florian,Michon, Christophe,Agbossou-Niedercorn, Francine
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supporting information
p. 6218 - 6227
(2013/01/15)
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- Reversible oxidative addition and reductive elimination of fluorinated disulfides at gold(I) thiolate complexes: A new ligand exchange mechanism
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Reaction of HAuCl4·3H2O with excess HSAr (Ar = C6F5 or C6F4H) in ethanol, followed by addition of [Et4N]Cl, produced [Et4N][Au(SAr) 4] (Ar = C6F5 (1a) or C6F 4H (1b)) as red crystalline solids in high yield. These complexes are rare examples of homoleptic gold(III) thiolate complexes. The crystal structures 1 show square planar geometry at the gold center with elongated Au-S bonds. Both complexes undergo reversible reductive elimination/oxidative addition processes in solution via thermal and photochemical pathways. Equilibrium constant and photostationary state measurements indicate that the relative importance of the two pathways depends on the nature of the aromatic groups. The metal-containing reductive elimination products, [Et 4N][Au(SAr)2] (Ar = C6F5 (2a) or C6F4H (2b)), were confirmed by both independent synthesis and crystallographic characterization. Cross-reactions between either 1 or 2 and various disulfides led to ligand exchange via an addition-elimination process, a previously unknown reaction pathway for ligand exchange at gold(I) centers.
- Bachman, Robert E.,Bodolosky-Bettis, Sheri A.,Pyle, Chelsea J.,Gray, Margaret Anne
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p. 14303 - 14310
(2009/03/11)
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- Pd(II) and Au(I) chloride complexes with tetrakis(butylthiomethyl)calix[4] arene: Synthesis and crystal structures
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Two novel complexes, (AuCl)4L3(I) and (PdCl 2)2L3(II) (L3 is calix[4]arene-thioether), were synthesized and their structures were determined. In complex I, one thioether group of molecule L3 is coordinated to every Au atom. In complex II, the bidentate coordination of L3 to the Pd atoms is observed; two thioether groups are in the trans-positions in the Pd square surrounding. Both complexes have the layered crystal lattices. In the Au complex, the layers are more stable due to the short contacts Au-Au (3.19-3.23 A).
- Kostin,Mashukov,Kurat'eva,Tkachev,Torgov,Drapailo
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p. 360 - 366
(2009/01/31)
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- Synthesis and characterization of 1-(3,5-di-tert-butyl)pyrazolyldiphenylphosphine and its gold(I) complex
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1-(3,5-Di-tert-butyl)pyrazolyldiphenylphosphine was prepared from 3,5-di-tert-butyl)pyrazole and chlorodiphenylphosphine. It reacted with (Me2S)AuCl to afford a Au(I) complex bearing the pyrazolylphosphine ligand in a monodentate coordination mode.
- Xia, Aibing,Seward, Corey,Voges, Mariza
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p. 1339 - 1341
(2008/10/09)
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- Electronic communication mediated by a PtI-PtI σ-bond
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A binuclear complex [Pt2(dppm)2(C≡CFc)2] (1) (dppm = bis(diphenylphosphino)methane, Fc = C5H5Fe≡C5H4, ferrocenyl) containing two redox-active ferrocenylacetylides linked by a PtI-PtI σ-bond is designed to probe electronic communication through a C≡C-Pt-Pt-C≡C linkage. The X-ray crystal structure of the complex shows a Pt-Pt bond distance of 2.7023(2) A? and a Fe-Fe separation of 14.474(2) A?. The cyclic voltammogram (CV) of 1 displays two quasi-reversible one-electron Fc oxidations (Δp ≈ 70 mV at 20 mV s-1, ipc/ipa ≈ 1) separated by 267 ± 10 mV, and accordingly the equilibrium constant for the comproportionation 12+ + 1 ? 2 1+ is estimated to be (3.3 ± 1.5) × 104. These suggest considerable electronic communication between the redox centers in the mixed-valence complex 1-. The UV-vis-NIR absorption spectrum of 1 shows an intervalence-charge-transfer band at 11 300 ± 50 cm-1 (∈max = 610 ± 10 M-1 cm-1), and the electronic coupling parameter HAB is estimated to be 190 ± 20 cm-1. Addition of d10 AuICl and AuIBr fragments to the Pt-Pt bond gives rise to two A-frame clusters [Pt2(μ-AuX)(dppm)2(C≡CFc)2] (X = Cl or Br), whose X-ray crystal structures are composed of isosceles triangles of Pt2Au. In contrast to 1, electronic communication through the Pt2Au cluster is very weak, as the CVs of the compounds exhibit no splitting of Fc oxidations. Possible reasons for the shutdown of electronic communication are discussed.
- Yip, John H.K.,Wu, Jianguo,Wong, Kwok-Yin,Ho, Kam Piu,Pun, Christine So-Ngan,Vittal, Jagadese J.
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p. 5292 - 5300
(2008/10/08)
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- Luminescent gold(i) macrocycles with diphosphine and 4,4'-bipyridyl ligands
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The complexes [{-Ph2P(CH2)aPPh2AuNC5H4C5H4NAu-y2l:+ [CF3CVL (/; = 1-6) were prepared as colourless, air-stable solids by reaction of silver trifluoroacetate with the corresponding precursor complex [(CH2)(Ph2PAuCl)2], and
- Brandys, Marie-Claude,Jennings, Michael C.,Puddephatt, Richard J.
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p. 4601 - 4606
(2007/10/03)
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- Complexes of gold(I) and platinum(II) with polyaromatic phosphine ligands
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Gold and platinum(II) complexes of the phosphine ligands PArnPh3-n (Ar=naphthyl, anthracenyl, ferrocenyl and other polyaromatic groups) have been synthesised. The electron donating abilities of naphthyl and anthracenyl phosphine ligands has been explored using gas phase photoelectron spectral data on the parent phosphines and their relative complexing ability to platinum precursor molecules has been assessed by means of synthetic studies and NMR experiments. Their steric parameters have been estimated by the Tolman cone angle methodology using X-ray crystallographic data. The molecular structures of the gold complexes [AuCl(PAn2Ph)]·CHCl3 and [Au(PFc2Ph)2]·CHCl3 have been determined.
- Mueller, Thomas E.,Green, Jennifer C.,Mingos, D. Michael P.,McPartlin, C. Mary,Whittingham, Conrad,Williams, David J.,Woodroffe, Thomas M.
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p. 313 - 330
(2007/10/03)
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- Binuclear and trinuclear gold-platinum complexes: The crystal structures of [PtCl(CE≡C-t-Bu)(μ-dppm)2Au][Cl]·CH 2Cl2 and [Pt(C≡C-t-Bu)2{(μ-dppm)AuCl2] (dppm = Ph2PCH2PPh2)
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Reactions of trans-[PtCl2(SMe2)2] with 1 or 2 equiv of AuC≡C-t-Bu give unstable complexes formulated as [PtCl(C≡C-t-Bu)(SMe2)2(AuCl)] and [Pt(C≡C-t-Bu)2(SMe2)2(AuCl)2] with the AuCl units probably bonded to the alkynylplatinum groups. Further reaction of these complexes with dppm, Ph2PCH2PPh2, gave the binuclear trans-[PtCl(C≡C-t-Bu)(μ-dppm)2Au]+Cl- and trans-[Pt(C≡C-t-Bu)2(μ-dppm)2Au] +Cl- and the trinuclear trans-[Pt(C≡C-t-Bu)2{(μ-dppm)AuCl}2]. A number of other routes to these and related complexes have been developed. The structures of trans-[PtCl(C≡C-t-Bu)(μ-dppm)2Au][Cl]·CH 2Cl2 [space group P21/a, Z = 4, a = 23.144 (5) A?, b = 23.752 (3) A?, c = 10.474 (4) A?, β = 99.15 (2)°, R = 0.034] and of trans-[Pt(C≡C-t-Bu)2{(μ-dppm)AuCl}2] [space group P1, Z = 2, a = 9.703 (3) A?, b = 14.362 (1) A?, c = 23.646 (3) A?, α = 75.805 (8)°, β = 83.87 (2)°, γ = 70.09 (2) A?, R = 0.027] were determined by X-ray crystallography.
- Manojlovi?-Muir, Ljubica,Henderson, Allan N.,Treurnicht, Ilse,Puddephatt, Richard J.
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p. 2055 - 2061
(2008/10/08)
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- Chemistry of the Group 1B Metals. XVII. Preparation of Some Gold(I) Acetylide Complexes Containing Group 5 Donor Ligands: Crystal and Molecular Structures of Au(C2C6F5)(PPh3)
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Experimentally convenient syntheses of a series of gold(I) acetylide complexes containing tertiary phosphines include reactions between AuCl(PR3) and alk-1-ynes, either in diethylamine in the presence of copper(I) halides, or with methanol/sodium methoxide.Yields are good to excellent; several compounds are light-sensitive, and react violently with chlorinated solvents.The crystal structure of Au(C2H6F5)(PPh3) has been determined.It is monomeric, with almost linear two-coordinate Au: Au-C 1.993(14), Au-P 2.274(3), CC 1.197(16) Angstroem.Crystals are monoclinic, space group P21/c, with a 16.104(2), b 8.653(1), c 17.560(3) Angstroem, β 112.98(1) deg, Z 4; 1761 data with I > 2.5?(I) were refined to R, Rw = 0.033, 0.034.
- Bruce, Michael I.,Horn, Ernst,Matisons, Janis G.,Snow, Michael R.
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p. 1163 - 1170
(2007/10/02)
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