Organo-gold

The approach comprises deposition-precipitation (DP) of Au(OH)3 onto the hydroxide surfaces of metal oxide supports from an alkaline solution of HAUCI4 [26] and grafting of organo gold complexes such as dimethyl gold (Ill)acetylacetonate (hereafter denoted as Au acac complex) [27] and Au(PPh3)(N03) [28] either in gas and liquid phase are advantageous in that a variety of metal oxides commercially available in the forms of powder, sphere, honeycomb can be used as supports. 

A series of gold(III) complexes with bipyridyl ligands have been shown to be cytotoxic [71]. The compounds [Au(bipyc-H)(OH)]PF6 (Aubipyc) (bipyc = 6-(l, l-dimethylbenzyl)-2,2 -bipyridine) and [Au(bipy)(OH)2]PF6 (Aubipy) (bipy = bipyridine) (Fig. 12) were particularly active [72], the former being an organo-gold(III) complex [73]. 

Tithiated dicarbaborane clusters yield (organo)gold-substituted clusters on reaction with T AuX or R2AUX compounds, also with hypercoordinate carbon atoms (equations 36-38)." " ... 

Several reports of organo-gold compounds have been published. In these studies, the main concern was to establish the oxidation state of gold atoms and to deduce whether the XPS data are consistent with the proposed molecular structure. Some of the compounds studied are shown below. 

Organometallic chemistry (see p. 1199) is not particularly extensive even though gold alkyls were amongst the first organo-transition metal compounds to be prepared. Those of Au are the most stable in this group, while Cu and Ag (but not Au ) form complexes, of lower stability, with unsaturated hydrocarbons. 

Other solutions to dealing with interferences in the detection of H O have included the use of a copperfll) diethyldithiocarbamate precolumn to oxidize the sample before it reaches the immobilized enzyme, as well as the use of a palladium/gold sputtered electrode which catalyzes the oxidation of hydrogen peroxide In addition, peroxidase has been used to catalyze the reaction between hydrogen peroxide and iodide ferrocyanide and organo-fluorine compounds Am-... 

Organo-copper cluster chemistry has only been developed in recent years as a result of the discovery of the effect of internal hgands (306). The few examples of or-gano-silver clusters resemble their copper counterparts, while the cluster chemistry of gold, though hmited, is unique. 

Many organo-derivatives of the Group Vb elements have been prepared. The substituted phosphines, arsines, and stibines (for example, CH3PH2, (CH3)2AsH, and (CH3)sSb) are, like their parent hydrides (p. 253), easily flammable, toxic, and only weakly basic toward H4. However, the fully substituted arsines and phosphines form surprisingly stable adducts with salts of univalent gold, divalent platinum and palladium,... 

A second important reaction of L-AuR species is the oxidative addition (see Oxidative Addition) of halogen or alkyl halides, which leads, at least in a first step, to organo(dihalo)gold(IIl) or diorgano(halo)gold(III) products. The structures are transformed from linear to square planar, and therefore cis and trans isomers are possible. The products may undergo secondary reactions and/or become subject to a reductive elimination (see Reductive Elimination) of other substituent combinations (equations 41 and 42). ... 

The three elements lithium, sodium, and potassium bear little resemblance to copper, silver, and gold in their inorganic derivatives but, with the exception of gold, they show more resemblance in their organo-metallic compounds. 

Wang, Q. Jakubowski, J. A. Sweedier, J. V. Bohn, P. W., Quantitative submonolayer spatial mapping of Arg-Gly-Asp-containing peptide organo-mercaptan gradients on gold with matrix-assisted laser desorption/ionization mass spectrometry, Anal. Chem. 2004, 76, 1-8... 

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