LAUSR

Abstract Novel dppm-ligated ruthenium-tin clusters have been prepared from the reaction of [Ru3(CO)10(μ-dppm)] with Ph3SnH. At room temperature and in the presence of Me3NO, [Ru3(CO)9(SnPh3) (μ-dppm) (μ-H)] (1) is produced from the formal loss of CO and Sn-H bond oxidative-addition. Treatment of 1 with a further two equivalents of Ph3SnH (in the presence of Me3NO) gave [Ru3(CO)7(SnPh3)2(μ-SnPh2)(μ-dppm)(μ-H)(μ3-H)] (2) which results from both Sn–H and Sn–C bond scission and contains two different hydride environments (μ and μ3) and a μ-SnPh2 moiety. Cluster 2 has 48 CVE (cluster valence electron) with three formal ruthenium-ruthenium bonds; two of those are very long and fall at the extreme end of distances attributed to ruthenium-ruthenium bonds. Thermolysis of 2 at 66 °C liberates benzene to give [Ru3(CO)8(SnPh3)(μ-SnPh2)(μ3-SnPh2)(μ-dppm)(μ-H)] (3). DFT calculations confirm that the hydride bridges one of the Ru-μ-SnPh2 bonds in 3. The solid-state structures of 2 and 3 have been determined by X-ray crystallography, and the bonding and ligand distribution have been investigated by DFT studies. The geometry-optimized structures are consistent with the solid-state structures.