Umsetzung von Cyclopentadienylmetallcarbonylen mit Thionylhalogeniden - Neue Synthese halogenoverbrückter Cp*Co-Komplexe / Reaction of Cyclopentadienyl Metal Carbonyles with Thionylhalides - New Synthesis of Halogeno-Bridged Cp*Co Complexes

Abstract

The reaction of Cp*Co(CO)2 with thionylchloride in hexane affords the doubly bridged dimer (Cp*CoCl2)2. Whereas the same reaction in more polar solvents such as CH2Cl2 or thf gives the triply bridged dinuclear cations in the salt [(Cp*Co)2(μ-Cl)3]2 [Co2Cl6], no influence of the solvent is observed in the reaction of Cp*Co(CO)2 with thionylbromide, which results in the formation of the neutral dimer (Cp*CoBr2)2. The X-ray structure analysis of (Cp*CoBr2)2 shows two edge-sharing octahedra, while that of [(Cp*Co)2(μ-Cl)3]2[Co2Cl6] shows two facesharing octahedra in the cation and two edge-sharing tetrahedra in the anion.

Pentaarylcyclopentadienyl Iron, Cobalt, and Nickel Halides

“…In addition to the divalent iron, cobalt, and nickel half-sandwich complexes discussed above, very few trivalent metal complexes of the type [Cp R MX 2 ] have been reported . In case of cobalt, the complexes [CpCoX 2 ] n (X = Cl, Br, I; n = 2 or more) were synthesized by decarbonylation of [CpCo­(CO)­X 2 ], but attempts to isolate and fully characterize these compounds were impaired by their instability .…”