119970-84-2Relevant academic research and scientific papers
Synthesis and characterization of (trifluoromethyl)gold complexes
Sanner, Robert D.,Satcher Jr., Joe H.,Droege, Michael W.
, p. 1498 - 1506 (1989)
The synthesis of (CF3)AuL (L = PMe3, PEt3, PPh3) from LAuCl and Cd(CF3)2·DME is described. These linear gold(I) compounds readily add excess halogen to form the predominantly trans square-planar gold(III) dihalides (CF3)AuX2(L) (X = Br, I). The use of stoichiometric (or less) halogen leads to a significant quantity of (CF3)2AuX(L) (L = PMe3, PEt3) which is shown to arise from trifluoromethyl/halogen ligand exchange between (CF3)AuL and (CF3)AuX2(L). No evidence for ligand exchange is found when L = PPh3. (CF3)2AuI(L) (L = PMe3, PEt3) may also be prepared in 80% yield from the oxidative addition of trifluoromethyl iodide to (CF3)AuL; experiments with the radical scavenger galvinoxyl suggest a radical chain mechanism for this CF3I addition. Close examination of the 1H and 19F NMR spectra for the new square-planar complexes reveals that downfield shifts occur for both nuclei when a cis halide is changed from Br to I; a trans halide causes an upfield shift upon this substitution. The cadmium reagent is, in general, ineffective for the preparation of Au(III) complexes since reduction to (CF3)AuL usually occurs. However, treatment of (CF3)2AuI(PMe3) with Cd(CF3)2·DME in the presence of excess CF3I leads to the high-yield synthesis of the tris(trifluoromethyl) species (CF3)3AuPMe3.
