Preparation and structural characterization of [(Ph3P)2N][HFeRu3(CO)13] and [(Ph3P)2N][HFe2Ru2(CO)13]

Article abstract of DOI:10.1021/ic50225a045

Reaction of [(Ph₃P)₂N][HFe(CO)₄] with Ru₃(CO)₁₂ and Fe₂Ru(CO)₁₂ in refluxing THF gives the new clusters [(Ph₃P)₂N][HFeRu₃(CO)₁₃] and [(Ph₃P)₂N][HFe₂Ru₂(CO)₁₃] in 47% and 4% yields, respectively. [(Ph₃P)₂N]-[HFeRu₃(CO)₁₃] has been characterized by its spectroscopic properties and by complete single-crystal X-ray and neutron diffraction studies. [(Ph₃P)₂N][HFeRu₃(CO)₁₃] crystallizes in the space group P1 with Z = 2. Unit cell dimensions from the neutron diffraction study at 15 K are a = 15.053 (2) ?, b = 9.073 (1) ?, c = 18.992 (3) ?, α = 104.75 (2)°, β = 109.58 (2)°, and γ = 86.95 (2)°. The structure was refined to R(F²) = 0.052 and R(wF²) = 0.057 with measured intensities of 8354 independent reflections. The [HFeRu₃(CO)₁₃]^- anion has a closed pseudotetrahedral structure with each Ru bearing three terminal carbonyls. Two terminal carbonyls are attached to Fe with two additional carbonyls occupying semibridging positions between Fe and two Ru atoms. The hydride ligand symmetrically bridges one of the Ru-Ru bonds. [(Ph₃P)₂N][HFe₂Ru₂(CO)₁₃] has also been characterized crystallographically. It crystallizes in the space group P1 with Z = 2. The unit cell dimensions at room temperature are a = 14.955 (2) ?, b = 18.144 (3) ?, c = 9.290 (2) ?, α = 101.54 (2)°, β = 95.03 (4)°, and γ = 84.04 (3)°. The structure was solved and refined to R(F) = 0.056 and R(wF) = 0.042 for 5886 independent reflections with I ≥ 3.0σ(I). The structure of [HFe₂Ru₂(CO)₁₃]^- is similar to that of [HFeRu₃(CO)₁₃]^- except that the anion possesses a full-bridging CO between the two Fe atoms and no semibridging CO's.