Organogold complexes

When 4, 4 -dimethyl-2 -(2-thienyl)-2 -oxazoline lithiated at is reacted with [Au (CgFs) (tht)] the organogold complex analogous to the previous example was obtained. 

For Au CVD an organogold complex, (trimethylphosphine)methylgold(l) ((Me3P) AuCHs), has been used with the result of selective deposition on —SH and —CH3 terminated SAMs maintained at 70 °C [81-83]. Further, CVD at 70 °C on SAMs with —SH, —CH3, and —OH terminal groups was studied by spectroscopic and microscopic analyses with the result that no penetration was observed for the-SH surface but was observed for the -CH3 and -OH surfaces. Standard thermal deposition of Au on the ASH surface showed, in contrast to CVD, that the penetration cannot be completely prevented [83]. 

Many organogold complexes are light sensitive, and it has proved advantageous to store them in the dark. Thus even a-silylmethyl complexes, which have been shown to be more stable in general than their purely organic counterparts, decompose to metallic gold under irradiation (173). 

A number of organogold complexes have been subjected to X-ray crystallographic studies, and sufficient data have been accumulated for meaningful comparisons of bond lengths to be made. A series of complexes of the type [AuR(PPh3)] have been studied, and the bond length data for... 

COMPARISONS OF ORGANOGOLD COMPLEXES WITH THOSE OF OTHER METALS... 

Probably the best-known pentanuclear organogold complex is the homoleptic complex [Au(p-mes)]5, whose synthesis by reaction of [AuCl(CO)] with the appropriate Grignard reagent in tetrahydrofuran solution [Eq. (50)] was first reported in 1983 by Floriani.143 An alternative synthetic procedure that takes place with precipitation of insoluble byproducts and uses a mesitylgold(I) derivative as a starting material [Eq. (51)] has been described more recently.31... 

Other examples of organogold complexes evaluated in vitro include [Au (bipydmb-H)(2,6-xylidine-H)]PF6 (Auxyl) [(bipydmb = 6-(l,l-dimethylbenzyl)-2,2 -bipyridine)] and [Au(pydmb-H)(AcO)2] (Aupy) (pydmb = 2-(l,l-dimethylben-zyl)-pyridine) (Fig. 11) [74]. 

II. SYNTHESIS OF a-BONDED ORGANOGOLD COMPLEXES A. Complexes of the Type [RAuL]... 

There now exists a large number of methods for the synthesis of organogold complexes with various ylide ligands. In an extensive reaction chemistry, successive oxidation of the gold centres [Au(I) -> Au(II) Au(III)] can often be accomplished. Ylide complexes of gold have therefore been summarized in the following sections regardless of their oxidation state. 

One advantage of using phosphine organogold complexes or clusters is that they do not contain chlorides, but one drawback is that they must be synthesized, and handled with care because of toxicity. Moreover, depending on the nature of the compounds, they are more or less stable in air and light. 

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