Dimolybdenum complexes with sulfide and thiolate ligands as precursors to mixed-metal clusters: crystal structure of [Mo2Ru2(µ3-S)2(µ-SPri)2(CO)4(η-C5H5)2]
Abstract
The reaction of [Mo2(CO)4(µ-C2Me2)(η-C5H5)2]1 with thiols, RSH, in boiling toluene provides a useful new route to the known compounds [Mo2(µ-S)2(µ-SR)2(η-C5H5)2](R = Et 2a or Pri2b) in 40–45% yield. Both compounds exist as two isomers which were separated by chromatography for R = Et. The sulfur ligands in these complexes are formed by dealkylation of the thiols at the dimolybdenum centre. Reaction of 2 with [Ru3(CO)12] in refluxing tetrahydrofuran produced high yields of the mixed-metal clusters [Mo2Ru2(µ3-S)2(µ-SR)2(CO)4(η-C5H5)2]3; the crystal structure of the Pri-substituted complex 3b has been determined. The cluster consists of a tetrahedral metal core with both Mo2Ru faces capped by triply bridging sulfides. One of the thiolate ligands still bridges the molybdenum–molybdenum edge, but the other has migrated to the ruthenium–ruthenium edge.