1 research outputs found
Facile Formation of Homoleptic Au(III) Trications via Simultaneous Oxidation and Ligand Delivery from [PhI(pyridine)<sub>2</sub>]<sup>2+</sup>
We
report the first examples of AuÂ(III) tricationic complexes bound
only by neutral monodentate ligands, which are a new class of gold
reagents. Oxidative addition to the bis-pyridine AuÂ(I) cation, [AuÂ(4-DMAP)<sub>2</sub>]<sup>+</sup>, using a series of dicationic IÂ(III) oxidants
of the general form [PhIÂ(L)<sub>2</sub>]<sup>2+</sup> (L = pyridine,
4-DMAP, 4-cyanopyridine) allows ready access to homoleptic and pseudo-homoleptic
AuÂ(III) complexes [AuÂ(4-DMAP)<sub>2</sub>(L)<sub>2</sub>]<sup>3+</sup>. The facile oxidative addition of AuÂ(I) species additionally demonstrates
the efficacy of PhIÂ(L)<sub>2</sub>]<sup>2+</sup> reagents as halide-free
oxidants for AuÂ(I). Comparisons are made via attempts to oxidize NHC-AuÂ(I)ÂCl,
where introduction of the chloride anion results in complex mixtures
via ligand and chloride exchange, demonstrating the advantage of using
the pyridine-based homoleptic compounds. The new AuÂ(III) trications
show intriguing reactivity with water, yielding dinuclear oxo-bridged
and rare terminal AuÂ(III)−OH complexes