Synthesis and X-ray structure of CO3(CO)9[CC(O)OCHC]Co2Fe(CO)9, an unexpected product of the reaction of [PPh4][HFe(CO)4] with [Co3(CO)9CCO][PF6]

Article abstract of DOI:10.1021/om00096a026

[Co₃(CO)₉CCO][PF₆] reacts at room temperature with [PPh₄][HFe(CO)₄] to give the complex Co₅Fe-(CO)₈[CC(O)OCHC] as the main product of the reaction (20% yield). An X-ray diffraction study shows that this complex consists of CO₃ and Co₂Fe triangles joined by a CC(O)OCHC group which can be described as an ester of a vinylidene group. The vinylidene part of the ligand is bonded to the Co₂Fe triangle. This compound crystallizes in the monoclinic space group C_2h⁵-P2₁/n with cell dimensions a = 8.645 (2) ?, b = 12.990 (2) ?,c = 26.883 (2) ?, β = 93.32 (2)°, and Z = 4. The structure was solved and refined to R and R_w values of 0.034 and 0.032, respectively, by using 5299 reflections. Other products isolated in this reaction are Co₃(CO)₉(μ₃-CH) (4% yield), Co₃(CO)₉(μ₃-CCH₃) (1% yield), Fe₃(CO)₁₂ (8% yield), HFe-Co₂(CO)₉(μ₃-CH) (traces), Fe₂Co(CO)₁₀(CCH₃) (traces), [Co₃(CO)₉C]₂CO (4% yield), and [Co₃(CO)₉C]₂ (4% yield).