Synthesis, Characterization, and Ethylene Oligomerization and Polymerization of [2,6-Bis(2-benzimidazolyl)pyridyl]chromium Chlorides

A series of [2,6-bis(2-benzimidazolyl)pyridyl]chromium chlorides have been synthesized and characterized by elemental analysis and IR spectroscopy, along with X-ray diffraction analysis for the structures of C1 and C7 . When methylaluminoxane (MAO) was employed as the cocatalyst, the chromium complexes showed high activity for ethylene oligomerization and polymerization. Oligomers were produced with high selectivity for α-olefins, and polyethylenes were generated with extremely broad molecular weight distributions. In the presence of diethylaluminum chloride (Et 2 AlCl), these chromium complexes showed moderate activity for ethylene polymerization and produced high-molecular-weight linear polyethylene.