Synthesis and structure of novel trinuclear and tetranuclear ruthenium carbonyl clusters containing mu(3)-P or mu(3)-PR and mu(3)-S bridging ligands

The reaction of [Ru-3(CO)(12)] with dimer of p-methoxyphenyl thionophosphin e sulfide in THF yields the novel trinuclear ruthenium carbonyl cluster [(m u -H)](2)Ru-3(CO)(9)(mu (3)-P)](I) and tetranuclear ruthenium carbonyl clus ter [Ru, (CO) to (P3-PC,,H4OMe) I ( I). These clusters were characterized b y elemental analysis, IR, H-1 NMR, P-31 NMR and MS spectrometric methods an d the molecular structure of compound I was determined by X-ray diffraction analysis. The molecular geometry of compound I contains a trigonal pyramid Ru3P skeleton with a Ru-3 triangle at the base and the nude phosphorus ato m as a 5e mu (3)-P bridging ligand at the apex. Though compound I is one wi th 49 valence eletron, its Ru-Ru distances(average 0. 283 0 nm) are astonis hly short and compound I is rather stable in the exposure to oxygen and moi sture. The structure of compound II is believed to have a tetrahedral Ru-4 core which is attached to a mu (3)-S and a mu (3)-PC6H4OMe ligand on tetrah edron's two triangular faces.