Coordination compounds of iron(II)chloride with bis(imino)pyridine ligands bearing omega-alkenyl substituents were synthesized and characterized. They can be activated with methylalumoxane (MAO) and then be used as self-immobilizing catalysts for the polymerization of ethylene. The produced polyethylene has a monomodal molecular weight distribution which is in contrast to polyethylenes that are produced with the unsubstituted catalysts. (c) 2006 Published by Elsevier B.V.