Structures and Reactivities of Palladium−Ruthenium Mixed-Metal Sulfido Clusters Derived from Disulfido- or Hydrosulfido-Bridged Diruthenium Complexes

• Published in: Organometallics Vol. 21; no. 24; pp. 5401 - 5407
• Main Authors: Kuwata, Shigeki, Hashizume, Kohjiro, Mizobe, Yasushi, Hidai, Masanobu
• Format: Journal Article
• Language: English
• Published: American Chemical Society 25.11.2002
• ISSN: 0276-7333; 1520-6041
• DOI: 10.1021/om020627l

The reaction of the disulfido-bridged diruthenium complex [Cp*Ru(μ2-S2)(μ2-SPri)2RuCp*] (1; Cp* = η5-C5Me5) with 2 equiv of [Pd(PPh3)4] in boiling toluene resulted in the formation of the palladium−ruthenium mixed-metal sulfido cluster [(Cp*Ru)2(μ3-S)2Pd2(μ2-SPri)(SPri)(PPh3)] (2). Upon treatment with benzyl bromide, stepwise substitution of the thiolato ligands in 2 by bromo ligands took place to afford the monobromo cluster [(Cp*Ru)2(μ3-S)2Pd2(μ2-SPri)Br(PPh3)] (4) and the dibromo cluster [(Cp*Ru)2(μ3-S)2Pd2(μ2-Br)Br(PPh3)] (5). On the other hand, the cationic palladium−ruthenium sulfido cluster [(Cp*Ru)2(μ3-S)2Pd2(μ2-Cl)(PPh3)2]Cl (7) was obtained by the reaction of the hydrosulfido-bridged diruthenium complex [Cp*RuCl(μ2-SH)2RuClCp*] (6) with 2 equiv of [Pd(PPh3)4]. The structural feature commonly observed for the 60e clusters 2, 4, 5, and 7 is the presence of a distorted-tetrahedral Pd2Ru2 core containing one Pd−Pd (2.780(1)−2.8130(8) Å) and one Ru−Ru bond (2.6231(7)−2.6386(9) Å) as well as four relatively long Pd−Ru contacts (2.831(1)−3.095(2) Å). Furthermore, 7 reacted with CO to afford the 64e carbonyl cluster [{Cp*Ru(CO)}2(μ3-S)2{PdCl(PPh3)}2] (8) with a boatlike Pd2Ru2(μ3-S)2 framework. The detailed structures of 2, 4, 5, 7, and 8 have been determined by X-ray crystallography.