Heterometallic multinuclear PtM (M=Au, Ag) structural assemblies from dinuclear [Pt2(PP)2(μ-S)2] (PP=2PPh3, dppf)

Three heterometallic PtM (M=Ag, Au) complexes, viz. [Au2{Pt2(PPh3)4(μ3-S)2}2]Cl2 (2), Au2Pt2Cl2(PPh3)4(μ3-S)2 (3) and Ag2Pt2Cl2(dppf)2(μ3-S)2 (4) (dppf=1,1′-bis(diphenylphosphino)ferrocene) were prepared from Pt2(PP)2(μ-S)2(PP=2PPh3 (1a), dppf (1b)) that has a butterfly {Pt2S2} core. The structures of 2 and 4 were determined by X-ray single-crystal diffractometry. Complex 2 has a hexanuclear {Au2Pt4} cage-framework comprising two hinged {Pt2S2} anchored across strong AuAu bond (2.837 Å). Complex 4 has a tetranuclear {Au2Pt2} open-framework, which contains a flattened {Pt2S2} butterfly with two AgCl ‘molecular pendants’ protruding perpendicularly out of the plane from the sulfur sites at opposite directions. The structural features of these polymetallic complexes and the synthetic and structural relationships between 2 and 3 are described.