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 ...