96897-80-2Relevant academic research and scientific papers
Synthesis, structure, and redox properties of [(η-C5H5)Fe{μ-σ:η4-NiC 4R4(η-C5H5)}]. A ferrocene analogue with a nickelapentadiene ring
Colbran, Stephen B.,Robinson, Brian H.,Simpson, Jim
, p. 1594 - 1601 (2008/10/08)
The reaction of [Fe2(CO)(μ-CO){μ-σ:η3-(CO)C 2RR′}(η-C5H5)2] (R = Ph or H; R′ = Ph) with nickelocene or [Fe2(CO)4(η-C5H5)2] with nickelocene and alkyne gave the brown heterodinuclear [η-C5H5Fe{μ-σ:η4-NiC 4R2R2′(η-C5H 5)}] (R = H, R′ = Ph (1); R = R′ = Ph (2)), the first examples of compounds with a nickelapentadiene ring. Compound 2, as a benzene solvate, crystallizes in space group C2/m with Z = 4 and lattice constants of a = 22.153 (8) A?, b = 18.850 (7) A?, c = 9.816 (4) A?, and β = 116.06 (3)°. The structure consists of an iron atom sandwiched between approximately coplanar η-C5H5 and σ:η4-NiC4Ph4 rings. The Fe atom is slightly displaced toward the nickel atom of the nickelapentadiene ring with Ni-Fe = 2.419 (2) A?. Compound 2 has a reversible one-electron oxidation at E1/2 = 0.67 V vs. Ag/AgCl, and green salts of 2+ have been prepared by chemical and electrochemical oxidation. An acid-mediated oxidation by O2 is described. The 1H NMR and electronic spectra of 1, 2, and 2+ are analyzed, and options for assignments of the near-infrared band in 2+ at 1110 nm are given. Photolysis of [Fe2(CO)4(η-C5H5)2] with PhC2H gives a differracyclopentadiene, [Fe2(CO)(μ-C4Ph2H2)(η-C 5H5)2], a possible intermediate in the above synthesis.
