Synthesis of homo- and heteronuclear ruthenium–gold clusters with diphosphine and thiolato bridged ligands. Single crystal molecular structure of [Ru3(CO)10(μ-AuPPh3)(μ-SC5H4N)] and [Ru3(CO)8(μ-H)(μ-SC5H4N)(μ-dppe)]

The reaction between [Ru3(CO)10(NCMe)2] and [AuClPPh3] gave compound [Ru3(CO)10(μ-Cl)(μ-AuPPh3)] (1) in quantitative yield under very mild conditions. The reaction of 1 with 4-mercaptopyridine (4-pyS) using ultrasonic reaction conditions gave the heteronuclear compound [Ru3(CO)10(μ-AuPPh3)(μ-SC5H4N)] (2) in moderate yield. There was no spectroscopic evidence that indicates the formation of the hydride isolobal analog in this reaction. The homonuclear cluster [Ru3(CO)8(μ-H)(μ-SC5H4N)(μ-dppe)] (3) was prepared by a selective reaction employing the ruthenium–diphosphine derivative [Ru3(CO)10(μ-dppe)] (dppe = 1,2-bis(diphenylphosphine)ethane) with 4-pyS in THF solution. The isolobal analog to compound 3, compound [Ru3(CO)8(μ-AuPPh3)(μ-SC5H4N)(μ-dppe)] (4) was synthesized by the reaction between compound 2 and dppe in refluxing dichloromethane. Compounds 1–4 were characterized in solution by spectroscopic methods and the molecular structure of compounds 2 and 3 in the solid state was obtained by single crystal X-ray diffraction studies.