The Unprecedented [S<sub>4</sub>N<sub>2</sub>O<sub>10</sub>]<sup>2−</sup> Anion in the Molecular Gold Complexes [Au<sub>2</sub>Br<sub>2</sub>(S<sub>4</sub>N<sub>2</sub>O<sub>10</sub>)<sub>2</sub>] and [Au<sub>2</sub>Cl<sub>2</sub>(S<sub>4</sub>N<sub>2</sub>O<sub>10</sub>)<sub>2</sub>](S<sub>2</sub>O<sub>5</sub>Cl<sub>2</sub>)
The reaction of hexachlorophosphazene, P3N3Cl6, with SO3 and the gold halides AuCl3 and AuBr3, respectively, leads to the new cyclic anionic tetramer, [S4N2O10]2−, which is coordinated to Au3 in the dimeric complexes [Au2X2(S4N2O10)2] (X=Cl, Br). The [S4N2O10]2− anion can be seen as the condensation product of two sulfate anions, [SO4]2−, and two amidosulfate anions, [NH2SO3]−.