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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1417-1422 
    ISSN: 0009-2940
    Keywords: Gold ; N ligands ; Gold(I) complexes ; (Imine)gold(I) complexes ; Guanidines ; Ketimines ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: (Tetramethylguanidine)gold(I) chloride (1) and bromide (2) are readily prepared in high yield from (Me2N)2C=NH and [AuCl(Me2S)] or [AuBr(tht) (tht = tetrahydrothiophene), repectively. NMR spectra of chloroform solutions of the two products indicate equilibria of the type 2 LAuX = L2Au+AuX2-. The cationic complex [Au(NH=C(NMe2)2)(PPh3)]+ is obtained as the triflate salt 3 from tetramethylguanidine and [Au(PPh3)]+O3SCF3-. In solution at low temperature (-60°C), this compound adopts a rigid structure whereby the NMe2 groups are rendered non-equivalent, but at ambient temperature there is coalescence of the NMe2 signals in the 1H- and 13C-NMR spectra. The related benzophenoneimine complex [Au{NH=CPh2}(PPh3)]+BF4- (4), which was synthesized as a reference3 compound, exhibits similar behaviour. In solution at low temperature (-60°C) the two phenyl rings of the ligand are diastereotopic. In contrast, the triisopropylphosphane derivative [Au[NH=CPh2](PiPr3)]+BF4- (5) is rigid on the NMR time scale, even at 25°C. Thbe solid-state structures of 2, 3, 4, and 5 have been determined by single-crystal X-ray diffraction. Compound 2 crystallizes in the ionic form with discrete Au … Au bonded ion pairs [Au[NH=C(NMe2)2]2]+ [AuBr2]- [Au … Au 3.1413(8) Å]. The cations of 3, 4, and 5 show the [Au(PPh3)]+ units N-coordinated to the imino groups, with the nitrogen atoms in a trigonal-planar configuration.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 221-223 
    ISSN: 0009-2940
    Keywords: Gold ; Polygoldammonium salts ; (1-Adamantyl)ammonium salts ; Trinuclear complex, X-ray structure of ; Tetranuclear complex ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of 1-adamantylamine with tris(triphenylphosphaneaurio)oxonium tetrafluoroborate results in the formation of the trinuclear adamantyltris(triphenylphosphaneaurio)ammonium tetrafluoroborate {C10H15[Au(PPh3)]3}+BF4-. The product can be further aurated by addition of equimolar amounts of triphenylphosphanegold(I) tetrafluoroborate to give the tetranuclear complex {C10H15N[Au(PPh3)]4}2+(BF4minus;)2. Both compounds have been fully characterized by analytical and spectroscopic data, and in the case of the trinuclear complex by a single crystal X-ray structure determination.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1423-1426 
    ISSN: 0009-2940
    Keywords: Gold ; Gold(I) complexes ; (Imine)gold(I)complexes ; Ketiminophosphanes ; (Ketiminophosphane)gold(I) complexes ; Ketiminophosphane sulfides ; (Ketiminophosphanesulfide)gold(I) complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reactions of chloro(dimethyl sulfide)gold(I) with equivalent quantities of the ketiminophosphane diphenyl(diphenylmethyleneamino)phosphane (1a) or its sulfide (1aS) lead to high yields of stable, crystalline 1 : 1 complexes with AuCl units attached to the phosphorus and sulfur atom, respectively. Tris(diphenylmethyleneamino)phosphane (1c) gives the related complex (Ph2C=N)3PAuCl with the gold atom also selectively P-bound. Bis(diphenylmethyleneamino)phenyl-phosphane (1b) could not be used because of its limited stability. Single-crystal X-ray diffraction studies have shown that there is no auxiliary coordination of the metal center by the imino functions of the ligands. The geometry of the P/S—Au—Cl moieties deviates only very slightly from linearity. The angle at the sulfur atom in (Ph2C=N)Ph2PSAuCl is very small [94.30(3)°], but despite of the resulting rather open coordination there are no discernible intra- or intermolecular contacts in the lattice. Such contacts are also absent with (Ph2C=N)Ph2PAuCl and (Ph2C=N)3PAuCl owing to the bulk of the ligands. The 1 : 1 complexes do not react with an excess of (Me2S)AuCl. This finding, and the molecular structures of the 1 : 1 complexes, show very consistently that both phosphane and sulfide donors are far superior as ligands for gold(I) as compared to ketimine donor molecules.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 641-646 
    ISSN: 0009-2940
    Keywords: Gold ; S ligands ; Carboxylato complexes ; Thioether complexes ; Sulfonium complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Treatment of 2-mercaptoaniline with {[(Ph3P)Au]3O}+ BF-4 leads to a regioselective auration to give the (2-aminophenyl)sulfonium complex {(2-H2NC6H4S[Au(PPh3)]2}+ BF-4 (1) as the sole product. With the same reagent, 4-hydroxyphenyl)sulfonium salt 2, and 2-mercaptopyridine is converted into the 2-pyridylsulfonium salt 3. Dinuclear auration of the thiol functions is thus clearly favoured over the reaction at any of the other functional groups (-NH2, -py, -OH). As shown in earlier work, this is also true for HS-functional carboxylic acids. With an excess of the oxonium reagent, however, 2-mercaptosuccinic acid was now found to be converted into a tetranuclear complex with a doubly aurated sulfonium group and monoaurated carboxylate functions (4). Bis(2-mercaptoethyl) ether and thioether react with the oxonium salt to give tetranuclear bis(sulfonium salts) 5, 6, with bifurcated {-S[Au(PPh3)]2}+ groups at both ends. Structural studies of compounds 1, 5 and 6 showed the cations to be aggregated into centrosymmetrical dimers through short Au-Au contacts. Compound 5 forms one-dimensional infinite chains through a similar aggregation via the two bifurcated sulfonium end groups of each individual dicationic unit. The dications of compound 6 are associated only into centrosymmetrical dimers leaving one of the two sulfonium groups of each unit without auriophilic contacts to neighbouring dications, probably owing to an internal Au-S contact with the thioether function.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1333-1338 
    ISSN: 0009-2940
    Keywords: Gold ; Gold(I) complexes ; Phosphinite complexes ; Phosphite complexes ; Configuration determination ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of compounds (R3P) AuMe with diphenylphosphinous acid Ph2P(O)H affords methane and neutral complexes of the type (R3P(O)Ph2 (1a: R = Me; 1b: R = Ph, lc: R = o-Tol). 1a, b are obtained in high yield, but the yield of lc is lower owing to a side-reaction which leads to a different product: Ph2P(OH)-Au-P(O)Ph2 (2). The crystal structure of 1a was determined by a single-crystal X-ray diffraction study. The compounds is a monomer with a linear P-Au-P′ axis and the phosphane and phosphinite ligands in a staggered conformation. In solution (CHCl3, CH2Cl 2/) compounds 1a-c undergo a ligand redistribution, establishing equilibria that involve ionic isomers of the type [R3P)2Au]+ [Au-(P(O)Ph2)2]-, which are readily identified through their NMR data. The analogous reaction of (R3P)b AuMe with dimethylphosphite (MeO)2P(O)H gives methane and the corresponding dimethylphosphites of the type (R3P)AuP(O)(OMe)2 (3a: R = Me; 3b: R = Ph; 3c: R= o-Tol). The crystal structure of 3b has also been determined. It features a linear structure with an eclipsed conformation of the ligands. In polar solvents (CHCl3, methanol) there is again an eqilibrium between neutral and ionic isomers, the latter comprising bis(phosphane)gold cations [(R3P)2Au]+ and {Au[P(O)-(OMe)2]2)- anions, as confirmed by NMR spectroscopy and mass spectrometry.
    Additional Material: 5 Ill.
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  • 6
    ISSN: 0009-2940
    Keywords: Gold ; Phosphanes ; Phosphaneimines ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: [Tris(dimethylamino)phosphane]gold(I) chloride, μ-tris-{[tris(dimethylamino)phosphane]gold(I)}oxonium tetrafluoroborate, {μ3-tris(dimethylamino)phosphaneimidotris[tris(dimethylamino)phosphane]gold(I)}(2+) bis(tetrafluoroborate) and N-trimethylsilyltris(dimethylamino)phosphaneimine were prepared using modifications of established procedures. Their structures were determined in single-crystal X-ray diffraction studies. The ligand (Me2N)3P, here introduced into gold(I) chemistry for the first time, lends high stability to these compounds through efficient steric shielding of the reaction sites and through a balanced electronic substituent effect. The structural details of the (Mr2N)3P groups are of current interest because of the unusual nonequivalent configuration of the nitrogen atoms in the dimethylamino groups. This behaviour has been observed for most of the (Me2N)3P units in the compounds studied in this work.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 15 (1976), S. 728-740 
    ISSN: 0570-0833
    Keywords: Gold ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The question raised in the title of this progress report is answered point for point with an emphatic “yes”: Ranging from metallic gold, via clusters of gold atoms in low valence states, compounds of AuI, AuII, AuIII, and AuV, organogold derivatives, ylide and carbene complexes, to the catalytic activity of gold it embraces a long-neglected area of chemistry holding promise of many a discovery.
    Type of Medium: Electronic Resource
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