UNCHARGED MIXED-LIGAND CLUSTERS WITH THE [FE4S4](- SYNTHESIS, STRUCTURAL CHARACTERIZATION, AND PROPERTIES OF THE FE(4)S(4)X((T)BU(3)P)(3) (X=CL, BR, I) AND FE4S4(SPH)(2)((T)BU(3)P)(2) CUBANES() AND [FE4S4](2+)CORES )

The reactions of the [Fe(4)S(4)X(4)](2-) cubanes (X = Cl, Br, I), A, w ith (t)Bu(3)P in CH3CN solution in the presence of NaBPh(4) afford the new, uncharged, mixed-ligand [Fe4S4-((t)Bu(3)P)(3)X] cubanes, B, that contain the [Fe4S4](+) core and show EPR spectra characteristic of a S = 1/2 ground state. In the presence of PhS(-) and PhSSPh, B undergoe s ligand exchange and a one e(-) oxidation to give the uncharged, mixe d-ligand [Fe4S4((t)Bu(3)P)(2)(SPh)(2)] cubanes, C, that contain the [F e4S4](2+) core. The solubility of B and C in many common nonpolar solv ents makes these clusters ideal for reactivity studies in noncoordinat ing media.