Chromium complexes ligated by 2-carbethoxy-6-iminopyridines: Synthesis, characterization and their catalytic behavior toward ethylene polymerization

Abstract

The titled chromium complexes ( C1– C6) were prepared by the reaction of CrCl 3(THF) 3 with the corresponding 2-carbethoxy-6-iminopyridines ( L1– L6) in dichloromethane. All the complexes were characterized by IR spectroscopy and elemental analysis. The unambiguous solid-state structures of C1, C3 and C5 were determined by X-ray crystallography. The chromium core was found to be coordinated by a molecule of 2-carbethoxy-6-iminopyridine and three atoms of chlorine to form a distorted octahedral coordination geometry. Activated with ethylaluminum dichloride (EtAlCl 2), these complexes showed notable catalytic activities for ethylene polymerization. The nature of the ligands and reaction parameters affected the properties of the resultant polyethylenes.