N-(2-Benzoylphenyl)benzamido nickel(II) complexes and polymerization reactivity

[N-(2-Benzoylphenyl)benzamido-κ2N,O](η1-benzyl)(trimethylphosphine)Ni(II) (3) is prepared by the reaction of potassium N-(2-benzoylphenyl)benzamide and Ni(η3-CH2C6H5)Cl(PMe3). When 3 is treated with one equivalent of B(C6F5)3, one obtains a zwitterionic complex, [PhC(O)C6H4NC(Ph)OB(C6F5)3-κ2N,O]Ni(η1-CH2C6H5)(PMe3) (4). When two equivalents of B(C6F5)3 is added, PMe3 is abstracted to give a η3-benzyl zwitterionic complex, [PhC(O)C6H4NC(Ph)OB(C6F5)3-κ2N,O]Ni(η3-CH2C6H5) (5). Solid structures of 4 and 5 were determined by X-ray crystallography. When ethylene is added to 5, low molecular weight polyethylene is obtained.