title: Synthesis, characterization and catalytic behavior toward ethylene of 2-[1-(4,6-dimethyl-2-benzhydrylphenylimino)ethyl]-6-[1-(arylimino)ethyl]pyridylmetal (iron or cobalt) chlorides.
abstract: A series of 2-[1-(4,6-dimethyl-2-benzhydrylphenylimino)ethyl]-6-[1-(arylimino)ethyl]pyridines was synthesized and used to prepare the iron(II) and cobalt(II) chloride complexes thereof. All organic compounds were fully characterized by elemental analysis, IR and NMR ((1)H/(13)C) spectroscopy, whilst the metal complexes were characterized by elemental analysis and IR spectroscopy as well as by single-crystal X-ray diffraction studies (for two representative cobalt complexes), which revealed that the geometry at the metal was either pseudo-square-pyramidal or trigonal bipyramidal. Upon activation with either methylaluminoxane (MAO) or modified methylaluminoxane (MMAO), all metal complex pre-catalysts exhibited high activities for ethylene polymerization. The iron pre-catalysts show much higher activity than did their cobalt analogues; however, the iron catalytic systems generally produced polyethylene of wide molecular weight polydispersity. At elevated reaction temperature, the polyethylene was of lower molecular weight, but revealed narrow polydispersity.
authors.affiliation: Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Shaoli
authors.initials: S
authors.lastname: Wang
authors.forename: Baixiang
authors.initials: B
authors.lastname: Li
authors.forename: Tongling
authors.initials: T
authors.lastname: Liang
authors.forename: Carl
authors.initials: C
authors.lastname: Redshaw
authors.forename: Yuesheng
authors.initials: Y
authors.lastname: Li
authors.forename: Wen-Hua
authors.initials: WH
authors.lastname: Sun
mesh_terms: D002384:Catalysis; D002712:Chlorides / Q000737:chemistry*; D003035:Cobalt / Q000737:chemistry*; D005030:Ethylenes / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*
chemical_list: D002712:Chlorides; D005030:Ethylenes; D009942:Organometallic Compounds; D011725:Pyridines; D003035:Cobalt; C036216:ethylene; D007501:Iron