Reactions of low-valent metal complexes with fluorocarbons. Part XVI. Hexakis(trifluoromethyl)benzene–nickel complexes

Abstract

Hexafluorobut-2-yne reacts with bis(cyclo-octa-1,5-diene)nickel to form (1,5-C₈H₁₂)Ni[C₆(CF₃)₆] and (1,5-C₈H₁₂)₂Ni₂[C₆(CF₃)₆](1,5-C₈H₁₂= cyclo-octa-1,5-diene). Cyclo-octa-1,5-diene is displaced from the mononuclear complex by Ph₂PMe, PhMe₂As, Ph₃P, (MeO)₃P, MeC(CH₂O)₃P to give the complexes L₂Ni[C₆(CF₃)₆][L = Ph₂PMe, PhMe₂As, Ph₃P, (MeO)₃P, and MeC(CH₂O)₃P]. The arsine complex is also formed from (PhMe₂As)₄Ni and CF₃CCCF₃, and the triphenylphosphine complex is formed by reaction of (Ph₃P)₂Ni(C₂H₄) with hexakis(trifluoromethyl)benzene. Treatment of the binuclear complex with (MeO)₃P or MeC(C H₂O)₃P gives [(MeO)₃P]₄Ni₂[C₆(CF₃)₆] and [MeC(CH₂O)₃P]₄Ni₂[C₆(CF₃)₆], respectively. It is suggested that these complexes are fluxional hexakis(trifluoromethyl)benzenenickel (II) compounds.