A new coordination mode for (pyrid-2-yl)thiolate (L) ligands: Synthesis and characterization of [Ru6(μ3-H)(μ5-κ2-L)(μ-CO)(CO)15]

The hexaruthenium cluster complexes [Ru6(μ3-H)(μ5-κ2-L)(μ- CO)(CO)15], HL = 2-mercaptopyridine (1) and 2-mercapto-6-methylpyridine (2), have been prepared by heating [Ru3(CO)12] with 0.5 equiv. of HL in THF at reflux temperature. An X-ray diffraction study on a crystal of complex 2 has determined that its metallic skeleton, a basal-edge-bridged square pyramid, is hold up by a (6-methylpyrid-2-yl)thiolate ligand. This ligand is attached to the four basal ruthenium atoms of the pyramid through the sulfur atom and to the edge-bridging ruthenium atom through the nitrogen atom. Such a coordination mode is unprecedented for (pyrid-2-yl)thiolate ligands.