Oxo sulfido heteronuclear titanium-rhodium clusters with an incomplete doubly-fused cubane structure

The unusual early-late oxosulfido complex [{CpTi}(2)(mu(4)-O)(mu(3)-S)(4){Rh49CO)(6))}] (2) results from carbonylation, under atmospheric pressure, of a purple solution obtained by mixing Cp2Ti(SH)(2) with {Rh(mu-Ome)(cod)}(2)](cod = 1,5-cyclooctadiene) and traces of water, which is responsible for the formation of the oxo ligand. Replacement reactions of only two of the carbonyl groups in 2 by P-donor ligands selectively gives the complexes [{CpTi}(2)(mu(4)-O)(mu(3)-S)(4){Rh-4(CO)(4)(PR3)(2)}] (PR3 = PPh3, P(OMe)(3), P(OPh)(3))). These unusual oxosulfido complexes show art incomplete double cubane-type structure formed by two cubane-like moieties "Rh2TiS2O"-each with one empty vertex-fused through a common "Rh2O" face, with the oxide ligand displaying an unusual tetracoordination.