Reactivity of an Arene Cobalt Triple Decker Complex Towards Various Ligands. Facile Arene Displacement in [Bis{(η5-pentamethylcyclopentadienyl)cobalt}μ-{η4:η4-toluene}]

Abstract

The triple decker complex [{(η-Cp*)Co}2-μ-{η4:η4-toluene}] 1b exhibits an unusual reactivity towards a variety of organic ligands, 1b reacts with CO, ethene, butadiene, H2, Al2O3, hexafluorobenzene, 1.5 Cod, 2-butyne, phenanthrene, naphthalene and the dinuclear Ni cluster [{(η3-Cp)NiP(C2H5)3}2] to form mainly mononuclear organocobalt complexes. Reaction of 1b with NO and the diazoalkanes di-t-butyl-diazomethane and 2-diazo-1, 1', 3, 3'-tetramethylcyclohexane results in the formation of the dinuclear complexes [{(η5-Cp*)CoNO}2], [{(η5-Cp))(dw-butyl-diazomethane)Co}2] and [{(η5-Cp*)(2-diazo-1, 1', 3, 3'-tetramethylcyclohexane)Co}2], respectively. In the reaction of 1b with elemental sulfur the formation of a tetranuclear Co-sulfide cluster is observed. In the majority of the reactions studied, 1b looses its toluene ligand already at room temperature indicating an unusual high and hitherto unprecedented reactivity of an arene triple decker complex. © 1995 Verlag der Zeitschrift für Naturforschung. All rights reserved.