110077-73-1Relevant academic research and scientific papers
Interconversion of persulfido, sulfur hydride, and hydride ligands coordinated to CpRu(PPh3)2+
Amarasekera, Jayantha,Rauchfuss, Thomas B.
, p. 3875 - 3883 (2008/10/08)
The electron-rich metallothiol CpRu(PPh3)2SH (1) has been prepared from the reactions of CpRu(PPh3)2Cl with NaSH and CpRu(PPh3)2H with elemental sulfur. Carbonylation of 1 gives CpRu(PPh3)(CO)SH whereas the carbonylation of CpRu(PPh3)2Cl is thermodynamically unfavorable. Protonation of 1 gives [CpRu(PPh3)2(SH2)]+. Alkylation of 1 gives thiol complexes [CpRu(PPh3)2(RSH)]+ (R = CH3); such complexes were also prepared directly from CpRu(PPh3)2OTf (OTf = CF3SO3) and RSH. The structure of the thiol complex [CpRu(PPh3)2(n-PrSH)]BF4·CH 2Cl2 was determined by X-ray methods. Crystal data: triclinic space group P1, with a = 13.308 (5) A?, b = 14.641 (7) A?, c = 13.205 A?, α = 113.64 (3)°, β = 110.01 (4)°, γ = 84.45 (3)°, V = 2212 (2) A?3, and Z = 2; structure solution and refinement based on 4091 reflections with I > 2.58σ(I) to give R = 0.054. [CpRu(PPh3)2(SH2)]+ reacts reversibly with H2 to give the dihydride [CpRu(PPh3)2H2]+. Analogous results were found for [((2-SC4H3)CH2C5H 4)Ru(PPh3)2]+; the S-bound thiophene ligand can be displaced by H2S, H2, H-, and SH-. [CpRu(PPh3)2(H2S)]+ oxidizes in air to give [CpRu(PPh3)2]2(μ-S2)2+ (2). Salts of 2 are formed in two-electron oxidations of 1 with Ph3CBF4, Cp2Fe+, and I2 as well as electrochemically. A presumed intermediate in this oxidation is [CpRu(PPh3)2]2(μ-S2)+. This mixed-valence compound disproportionates upon addition of HOTf to give 2 and [CpRu(PPh3)2(SH2)]+. The reaction of 1 with sulfur gave ruthenium polysulfides [CpRu(PPh3)]2Sx (x = 4, 6).
Synthesis, structure, and properties of [CpRu(PR3)2]2(μ-S2)2+. Effects of strong π-donation in a disulfur complex
Amarasekera, Jayantha,Rauchfuss, Thomas B.,Wilson, Scott R.
, p. 3328 - 3332 (2008/10/08)
Compounds of the type [CpRu(PR3)2]2(μ-S2)[BF 4]2 were prepared via the unusual reaction of CpRu(PR3)2Cl, S8, and silver salts. Another route to these dimers includes the displacement of dihydrothiophene from [CpRu(PPh3)2(SC4H6)]+ with elemental sulfur. Optical and Raman spectroscopic studies of the dications indicate that their green colors (λmax = 718 nm) arise from transitions within the Ru2S2 core. Cyclic voltammetric measurements indicate that the dication can be oxidized (for the PMe3 derivative) and, in two well-separated steps, reduced. Salts of [CpRu(PPh3)2]2(μ-S2)+ were prepared via reduction of the dication with Et3N, benzyl alcohol, or thiophenol. The EPR spectrum of the monocation shows a five-line pattern indicating the equivalency of the four phosphorus centers. The structure of [CpRu(PMe3)2]2(μ-S2)[BF 4]2·2C6H5NO2 was determined by X-ray diffraction. The compound crystallized in the monoclinic space group P21/c with a = 8.424 (2) A?, b = 18.117 (5) A?, c = 17.424 (3) A?, and β = 92.13 (2)°. The structure was refined to a final R = 0.053 (Rw = 0.062). The dication is centrosymmetric with short Ru-S (2.208 (3) A?) and S-S (1.962 (4) A?) distances. The structure, electrochemistry, and stoichiometry of the dication indicate a delocalized, multiply bonded Ru..-S..-S..-Ru core.
