Complexes of gold

Gold(I) salts of oxo-acids are not known, but many complexes of gold(I) have been discovered. 

THE CONSTANTS OF REPLACEMENT AND THE CONSTANT OF STABILITE MIXED BROMID-THIOUREA COMPLEXES OF GOLD (HI)... 

The phosphine and arsine complexes of gold(I) have been intensively studied since the early 1970s. The possibilities of coordination numbers between 2 and 4 have been explored, though the use of bulky ligands is less essential than with the isoelectronic M(PR3)2 (M = Pd, Pt) compounds and the coordination numbers depend on both steric and electronic factors [71]. 

Apart from Au(N03)4, relatively few complexes of gold(III), and only those with O-donors, have been examined. Two that demonstrate the preference of gold(III) for square planar coordination are SrAu2(MeCOO)8 and SrAu2(OH)8 in the latter Au(OH)4 has Au-O 1.98 A [117]. 

Cinellu, M.A., Minghetti, G., Pinna, M.V., Stoccoro, S., Zucca, A., Manassero, M. and Sansoni, M. (1998) X-Oxo and alkoxo complexes of gold(III) with 6-alkyl-2,2 -bipyridines. Synthesis, characterization and X-ray structures. Journal of the Chemical Society,... 

Crystal and molecular structure of a macrocydic complex of gold(III). Inorganic Chemistry, 20, 853. 

Bortoluzzi, M., De Faveri, E., Daniele, S. and Pitteri, B. (2006) Synthesis of a new tetrakis(2-pyridinyl)pyrazine complex of gold(III) and its computational. 

Beagley, B. and Sandbank, J. (1992) Complexes of gold(III) with mononegative bidentate N,0-ligands. Journal of the Chemical Society, Dalton Transactions, (12), 1907. 

Uson, R., Royo, P. and Laguna, A. (1974) Reactions of complexes of gold(I) with bis (pentafluorophenyl)thallium(III) halides. Journal of Organometallic Chemistry, 69(3), 361-365. 

Uson, R., Laguna, A., Vicente, J., Garcia, J. and Bergareche, B. (1979) Preparation of pentahalophenyl p-tolyhsocyanide complexes of gold(l) and their reactions with amines, ammonia and alcohols. 

Raubenheimer, H.G., Lindeque, L. and Cronje, S. (1996) Synthesis and characterization of neutral and cationic diamino carbene complexes of gold(I). Journal of Organometallic Chemistry, 511 (1-2), 177-184. 

Desmet, M., Raubenheimer, H.G. and Kruger, G.J. (1997) Synthesis and Characterization of Thienyl Oligomeric, Carbene, and Nitrogen-Donor Complexes of Gold(I). Organometallics, 16(15), 3324-3332. 

Minghetti, G., Bonati, F. and Banditelli, G. (1976) Carhene Complexes Of Gold (III) And Reactions Of Coordinated Ligand. Inorganic Chemistry, 15(7), 1718-1720. 

McCleskey, T.M. and Gray, H.B. (1992) Emission spectroscopic properties of 1,2-bis(dicyclohexylphosphino)ethane complexes of gold(l). Inorganic Chemistry, 31, 1733-1734. 

Balch, A.L., Fung, E.Y. and Olmstead, M.M. (1990) Polynuclear ((diphenylphosphmo)methyl) phenylarsine bridged complexes of gold(I). Bent chains of gold(I) and a role for Au(I)—Au(I) interactions in guiding a reaction. Journal of the American Chemical Society, 112, 5181-5186. 

Dithiocarbamate complexes of gold and their derivatives have been increasingly studied in recent years, being prepared with both gold(I) and gold(III). Complexes have been made featuring both monodentate and bidentate dithiocarbamate ligands. 

Chernyak, A. S. and Shestopalova, L.F. (1976) Study of complexes of gold(I) with cysteine in an alkaline medium. Russian Journal of Inorganic Chemistry, English Translation, 21, 464—465. 

Seward, T.M. (1973) Thio complexes of gold and the transport of gold in hydrothermal solutions. Geochim. Cosmochim. Acta, 37, 379-399. 

Bis(ethylenediamine)gold(III) chloride reacts with /3-diketonates in aqueous base via Schiff base condensation to form complexes of gold(III) with a 14-membered macrocyclic tetraaza ligand such as (292).1711-1713 The X-ray structure showed the cation to be nearly planar. Delocalization of -electrons within the six-membered /3-diketonate rings was indicated by the observed pattern of C—C and C—N distances. Open-chain tetraaza ligand complexes in which condensation of only one /3-diketonate has occurred, can be isolated as intermediates in this reaction. They may be used for further condensation with a different /3-diketonate. Oxidation of this complex with trityl tetrafluoroborate introduces a double bond in position C2C3.1712,1714... 

The first carbonyl complex of gold, [AuCl(CO)], was prepared in 192 52080,2081 and since then only a few more derivatives have been obtained. The [AuBr(CO)] derivative was prepared later and is unstable in the solid state.2082,2083 The reductive carbonylation of Au(S03F)3 in fluorosulfonic acid leads via [Au(CO)2]+ (solvent) to solid [Au(S03F)(C0)] (Scheme 30).2084 [Au(CO)2]+ salts are produced in strongly ionizing protic acids or in Lewis acids such as SbF5. 

Complexation of gold ions, [Au(I)], with peripheral phosphine groups of a P-based dendrimer was reported by Majoral et al. [185]. Transmission electron microscopy (TEM) was used to analyze the large aggregates formed by the dendritic gold complexes and a direct correlation was observed between the size of the particles and the dendrimer generation number. In a recent report [186], Majoral et al. further demonstrated that up to 48 diphosphino groups could be anchored to the surface of dendrimers and various dendritic metal-complexes... 

The development of more benign alternatives to cyanide for gold-leaching (see Section 9.17.3.1) such as thiourea, thiocyanate, or thiosulfate, which form stable complexes in water has prompted research to identify suitable solvent extractants from these media. Cyanex 301, 302, 272, Ionquest 801, LIX 26, MEHPA, DEHPA, Alamine 300 (Table 5) have been evaluated as extractants for gold or silver from acidic thiourea solutions.347 Whilst the efficacy of Cyanex 301 and 302 was unaffected by the presence of thiourea in the aqueous feed, the loading of the other extractants is severely depressed. Formation of solvated complexes of gold and of an inner-sphere complex of silver has been proposed.347... 

Ylide complexes of gold are unique in that they exhibit an exceptional chemical and thermal stability, which facilitates preparative and structural work very considerably. It was in this class of compounds that a large variety of true organogold(ll) and mixed valence organogold(l)/(lIl) complexes was discovered. These are rare in the remainder of organogold chemistry. 

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