Chiral metal complexes. Part III. Nickel(0) complexes containing the bulky chiral ligand tri[(+)-bornan-2-yl] phosphite

Abstract

Co-ordinatively unsaturated Ni⁰ complexes [Ni(tbp)₂], [Ni(tbp)₃], [Ni(tbp)₂L], and [(tbp)₂Ni(µ-cod)Ni(tbp)₂]{tbp = tri[(+)-bornan-2-yl] phosphite, cod =η-cyclo-octa-1,5-diene, and L = mono-olefin} have been prepared. The cod-bridged complex is versatile in affording a variety of stable nickel complexes, e.g.[NiCl(tbp)₂R], [NiCl(tbp)₂(COR)], and [Ni(tbp)₂L](R = aryl). The unusual stability of these complexes may be due to the bulkiness of the phosphite ligands. Asymmetric induction has been observed in the formation of complex [Ni(CH₂:CH·CO₂H·CH₂CF₃)(tbp)₂].