Heterobimetallic cubane-like cluster compounds prepared as the homologous series [(η5-CP′)3Mo3S4M′(PPh3)]+ (M′ = Ni, Pd, Pt).: Crystal structures show that platinum is smaller than palladium

Exchange of the aqua ligands in [(H2O)(9)Mo3S4][Pts](4). 9H(2)O for Cp ' ligands (Cp ' = methylcyclopentadienyl; pts = p-toluenesulfonate) yielded the novel cluster salt [(eta (5)-Cp ')(3)-Mo3S4] [Pts] ([1] [pts]). Reactions of [1] [pts] in the presence of triphenylphosphane with [Ni-(cod)(2)] (cod = 1,5-cyclooctadiene) or [Pd-2(dba)(3)] (dba = dibenzylidenacetone) afforded the heterobimetallic cubane-like cluster compounds [(eta (5)-Cp ')(3)Mo3S4M ' (PPh3)][pts] ([2] [pts]: M ' = Ni; [3] [pts]: M ' = Pd). By reaction of [1] [pts] with [Pt(nor)(3)] (nor = 2-norbornene) at ambient temperature [(eta (5)-Cp ')(3)Mo3S4Pt(nor)][pts] ([4][pts]) was isolated and further converted to [(eta (5)-Cp ')(3)Mo3S4Pt(PPh3)] [Pts] ([5][pts]) at 60 degreesC. A P-31{H-1} NMR spectroscopic characterization of [5] [pts] revealed a coupling constant (1)J(PtP) of 6656 Hz, whose size supports the view that the platinum atom is Pt-0- rather than Pt-II-like. Single-crystal X-ray studies of the complete homologous series [2][pts], [3][pts], and [5][pts] demonstrated that the cluster cations are isostructural with M ' -P bond lengths in the order Ni < Pt < Pd.