2-(1H-2-Benzimidazolyl)-6-(1-(arylimino)ethyl)pyridylnickel Complexes: Synthesis, Characterization, and Ethylene Oligomerization

A series of tridentate N,N,N-nickel complexes bearing 2-(1H-2-benzimidazolyl)-6-(1-(arylimino)ethyl)pyridines was synthesized and characterized by elemental and IR spectroscopic analysis. The molecular structures of representative complexes were determined by single-crystal diffraction, and these were found to have a six-coordinate distorted octahedral geometry around the Ni centre. On treatment with Et2AlCl, all nickel complexes exhibited good catalytic activities up to 106 g mol–1(Ni) h–1 for ethylene oligomerization with major dimerization. The steric and electronic effects on catalytic activities of metal complexes as well as the influence of various reaction parameters were carefully investigated.