2‐(1‐(2,4‐Bis((di(4‐fluorophenyl)methyl)‐6‐methylphenylimino)ethyl)‐6‐(1‐(arylimino)ethyl)pyridylmetal (iron or cobalt) Complexes: Synthesis, Characterization, and Ethylene Polymerization Behavior

A series of 2‐(1‐(2,4‐bis((di(4‐fluorophenyl)methyl)‐6‐methylphenylimino)ethyl)‐6‐(1‐(aryl­imino)ethyl)pyridines is synthesized and used to form their corresponding iron(II) and cobalt(II) chloride complexes thereof. All the organic compounds are fully characterized by elemental analysis, and IR and 1H/13C NMR spectroscopy, whereas the corresponding iron and cobalt complexes are characterized by elemental analysis and IR spectroscopy, as well as single‐crystal crystallography for the Fe2, Co1, and Co2 complexes, revealing a distorted trigonal bipyramidal structure. Upon activation with either methylaluminoxane (MAO) or modified methylaluminoxane (MMAO), all the iron complexes exhibit high activities toward ethylene polymerization at 60 °C; meanwhile, all the cobalt analogs demonstrate slightly lower activities at the optimized temperatures of 60 °C (MAO as cocatalyst) or 70 °C (MMAO as cocatalyst). All the polyethylenes obtained from cobalt precatalysts possess narrow polydispersity and lower molecular weights than those from their iron analogs.