The homoleptic compound [PPh4][CF3AuCF3] cleanly undergoes photoinduced oxidative addition of CF3I to afford the organogold(III) derivative [PPh4][(CF3)3AuI] in good yield and under mild conditions. This compound provides a convenient entry to the chemistry of the perfluorinated (CF3)3Au fragment, the properties of which were analyzed with the aid of DFT methods and compared with those of the homologous non‐fluorinated (CH3)3Au moiety. It was found that reductive elimination of CX3−CX3 in the former (X=F) requires a much higher energy barrier than in the latter (X=H) and is therefore considerably less favored. This can be considered as one of the main features underlying the significantly higher stability associated to the (CF3)3Au fragment and its derivatives. This unsaturated, 14‐electron species can be stabilized by coordination of any of the halide ligands, including fluoride. In fact, the whole series of anionic [PPh4][(CF3)3AuX] complexes (X=F, Cl, Br, I, CN) has now been isolated and conveniently characterized. Evidence for intermolecular decomposition pathways upon thermolysis in the condensed phase is presented.

Trifluoromethylation of AuCl3 by using the Me3 SiCF3 /CsF system in THF and in the presence of [PPh4 ]Br proceeds with partial reduction, yielding a mixture of [PPh4 ][Au(I) (CF3 )2 ] (1') and [PPh4 ][Au(III) (CF3 )4 ] (2') that can be adequately separated. An efficient method for the high-yield synthesis of 1' is also described. The molecular geometries of the homoleptic anions [Au(I) (CF3 )2 ](-) and [Au(III) (CF3 )4 ](-) in their salts 1' and [NBu4 ][Au(III) (CF3 )4 ] (2) have been established by X-ray diffraction methods. Compound 1' oxidatively adds halogens, X2 , furnishing [PPh4 ][Au(III) (CF3 )2 X2 ] (X=Cl (3), Br (4), I (5)), which are assigned a trans stereochemistry. Attempts to activate CF bonds in the gold(III) derivative 2' by reaction with Lewis acids under different conditions either failed or only gave complex mixtures. On the other hand, treatment of the gold(I) derivative 1' with BF3 ⋅OEt2 under mild conditions cleanly afforded the carbonyl derivative [Au(I) (CF3 )(CO)] (6), which can be isolated as an extremely moisture-sensitive light yellow crystalline solid. In the solid state, each linear F3 C-Au-CO molecule weakly interacts with three symmetry-related neighbors yielding an extended 3D network of aurophilic interactions (Au⋅⋅⋅Au=345.9(1) pm). The high $\tilde \nu $CO value (2194 cm(-1) in the solid state and 2180 cm(-1) in CH2 Cl2 solution) denotes that CO is acting as a mainly σ-donor ligand and confirms the role of the CF3 group as an electron-withdrawing ligand in organometallic chemistry. Compound 6 can be considered as a convenient synthon of the "Au(I) (CF3 )" fragment, as it reacts with a number of neutral ligands L, giving rise to the corresponding [Au(I) (CF3 )(L)] compounds (L=CNtBu (7), NCMe (8), py (9), tht (10)).

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