2,6-Dibenzhydryl-N-(2-Phenyliminoacenaphthylenylidene)-4-Chloro-Aniline Nickel Dihalides: Synthesis, Characterization and Ethylene Polymerization for Polyethylenes with High Molecular Weights

A series of 2,6-dibenzhydryl- N -(2-phenyliminoacenaphthylenylidene)-4- chloroanilines ( L1-L5 ) and their nickel halide complexes LNiX (X = Br, C1-C5 ; X = Cl, C6-C10 ) were synthesized. All organic compounds were characterized by FT-IR and NMR spectroscopy and elemental analysis. The nickel complexes were characterized by FT-IR spectroscopy, elemental analysis and their structures were determined by single-crystal X-ray diffraction. Upon activation with MAO, all of these nickel complexes showed high activities (up to 10 7 g of PE (mol of Ni) ^-1 h ^-1 ) for ethylene polymerization. The resulting polyethylenes possess high molecular weights (M _w up to 10 ⁶ g mol ^-1 ) and feature high degrees of branching. The MM-QEq method was employed to assess the ligands' effects on catalytic activities. The results show that higher net charges on the nickel core correlate directly with higher measured activities.