Pentafluorophenylgold

The first synthesized pentafluorophenylgold(I) complex was [Au(C6F5)PPh3[ obtained by the reaction of [AuClPPhs] and CgFsMgBr [30-32]. This complex was at the same time the first characterized [33] by X-ray studies showing the common nearly linear distribution of the phosphorous and the ipso carbon atom (178(1)°). Nowadays, there are many methods of obtaining this complex, in many cases as a by-product of some reaction and, in other cases, its formation is the driving force of the reaction. We will see examples of both in this chapter. 

Neutral Pentafluorophenylgold(l) Derivatives with C-Donor Ligands... 

When 4, 4 -dimethyl-2 -(2-thienyl)-2 -oxazoline lithiated at is reacted with [Au (C6F5)(tht)] the neutral nitrogen-coordinated pentafluorophenylgold complex and not the expected monocarbene complex [68] is obtained. 4-Methylthiazole, 4-methyl-2-mehylsulfanylthiazole and piperidine react with [Au(C6F5)(tht)] forming the complexes shown in Figure 3.4 [73]. 

Two different strategies can be used for the synthesis of di- and trinuclear pentafluorophenylgold(I) derivatives using [Au(QF5)(tht)] as one of the starting materials. 

PentqfluorophenYlgold(l) Derivatives 109 Table 3.4 Di and trinuclear pentafluorophenylgold(l) derivatives... 

All known pentafluorophenylgold(I) iron complexes are derivatives of ferrocene. In fact, they are obtained mainly by reaction of [Au(CgF5) (tht)] with modified ferrocenes... 

The complex obtained with ferrocenylmethylpyrazole (9) is noteworthy because the structure [151] shows the molecules associated into pairs via intermolecular Au Au interactions of 3.1204(6) A and these pairs form chains held together by H Au and H F interactions. The 3D supramolecular structure is formed through additional C— H F hydrogen bonds. These types of H F and H Au interactions are not common in pentafluorophenylgold chemistry. 

Heteronuclear Pentafluorophenylgold(l) Chromium, Cold Molybdenum and Cold Tunsten Complexes... 

The most general method of preparing pentafluorophenylgold(III) derivatives is oxidative addition with the appropriate oxidant to the gold(I) complex. The choice of... 

Other oxidants such as TCNQ (7,7, 8,8 -tetracyanoquinodimethane) can be used to oxidize a pentafluorophenylgold(I) complex, as takes place in the case of Q2[Au2(p,-dmit)(C6F5)2], which in the presence of TCNQ evolves in the oxidation of one gold atom giving a gold(III) [108] complex according to Equation 3.20... 

An important number of polynuclear pentafluorophenylgold(III) and mixed gold (I)-gold(III) derivatives have been described with the diphosphine 1,2-diphosphmo-benzene, which contains four hydrogen atoms that can be removed and substituted by a metal atom (Scheme 3.5) [220]. 

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