Gold complexes carbon-donors

Phosphonium ylides, which can be written in the two familiar canonical forms, are available with a wide variety of substituents both at the phosphorus and at the carbon atoms (Scheme 30). In gold complexes, without any exceptions, they function as two-electron donors, as proposed by the dipolar form to give discrete Au-C cr-bonds (771, monohapto). No side-on, 7r-coordination (t 2), as might be expected out of the ylene form, has been observed to date. 

Figure 1.31 Oligomeric gold(l) complexes with carbon donor ligands.

The majority of gold(III) complexes with carbon donor ligands are with alkyl and mainly aryl ligands and several methods exist for their synthesis ... 

COMPLEXES OF GOLD(I) WITH CARBON DONOR LIGANDS 885... 

COMPLEXES OF GOLD(III) WITH CARBON DONOR LIGANDS 898... 

The presence of an excess of electron density on the carbon atom in methanide gold (III) complexes permits them to act as C-donor nucleophiles forming dinuclear or even polynuclear derivatives. 

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