Iron(III) complexes with meta-substituted bis(arylimino)pyridine ligands: Catalyst precursors for the selective oligomerization of ethylene

Abstract

Bis(arylimino)pyridine iron(III) complexes containing meta-halogen substituents at the iminophenyl rings were synthesized and characterized. In contrast to iron(II) complexes, the presence of at least one ortho-substituent at the iminophenyl rings is not obligative for catalytic activities of these iron(III) complexes. After activation with methylaluminoxane (MAO), these catalysts oligomerize ethylene to give also internal and branched olefins besides the expected linear α-olefins. The widths of the resulting molecular weight distributions and the degrees of isomerization of the resulting oligomers strongly depend on the substitution pattern at the ligand frameworks.