Mixed main group transition metal clusters: Reactions of [Ru 3 (CO) 10 (μ-dppm)] with Ph 3 SnH

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 ( and 3) and a -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 o C liberates benzene to give [Ru3(CO)8(SnPh3)(µ-SnPh2)(µ3-SnPh2)(µ-dppm)(-H)] (3). DFT calculations confirm that the hydride bridges one of the Ru--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.2

Reactions of Ru3(CO)10(μ-dppm) with Ph3GeH: Ge–H and Ge–C bond cleavage in Ph3GeH at triruthenium clusters

“…2 and A1 is computed to be 3.8 kcal/mol (G) more stable than A2. This locus preference for the ancillary Ph3Ge ligand follows that recently computed by us for the corresponding Ph3Sn derivative [Ru3(CO)9(SnPh3)(µ-dppm)(µ-H)] [27], whose stereoisomers differ in energy by 2.2 kcal/mol in favor of the syn disposed Ph3Sn and hydride groups.…”

“…The resulting heterogeneous nanoparticle catalysts may be prepared by the deposition of a metal cluster containing a Group 14 ligand on an oxide support, yielding systems that exhibit high activity and selectivity for certain types of hydrogenation and dehydrogenation reactions [4]. We have been investigating the synthesis and structure of metal carbonyl complexes containing organogermanium and organotin ligands that can be used as precursors in the synthesis of such nanoscale catalysts during the last few years [5][6][7][8]. Ruthenium combined with the Group 14 elements, such as germanium or tin, continues to dominate the attention of different research groups with interest in catalysis [9][10][11].…”