Synthesis of 2,4,6-tris(trifluoromethyl)phenyl complexes of gold and thallium

Reaction of [AuCl(AsPh3)] with [LiFmes] (Fmes=2,4,6-tris(trifluoromethyl)phenyl) leads to the gold(I) complex [Au(Fmes)(AsPh3)], which can be used as precursor to other gold(I) complexes by displacement of AsPh3. Thus, treatment with diphosphines leads to mono- or dinuclear gold(I) complexes, namely [Au(Fmes)(dppm)], [Au(dppe)2][Au(Fmes)2] or [{Au(Fmes)}2(μ-PP)] (PP: bis(diphenylphosphino)methane (dppm), 1,2-bis(diphenylphosphino)ethane (dppe)). X-ray diffraction studies of [{Au(Fmes)}2(μ-PP)] show the expected trans-conformation for dppe but an unexpected gauche conformation for the dppm derivative. There are no short gold–gold contacts. The ionic nature of [Au(dppe)2][Au(Fmes)2] was also established by X-ray methods. Reaction of TlCl3 with [LiFmes] affords [Tl(Fmes)3], which does not react further with gold(I) derivatives to give gold(III) derivatives.