title: Organoactinides in the polymerization of ethylene: is TIBA a better cocatalyst than MAO?
abstract: The synthesis of two pyridylamidinate bis(N,N'-bis(trimethylsilyl)-2-pyridylamidinate)An(μ-Cl)2Li(TMEDA) (An = U (1), Th (2)) complexes is presented. For complex 1 the solid state X-ray structures were studied and compared to that of complex 2. The organoactinide complexes were studied as pre-catalysts in the polymerization of ethylene when activated by methylalumoxane (MAO). The catalytic activity was improved using a mixture of trityl tetrakispentafluorophenylborate (TTPB) and a small amount of methylalumoxane (MAO) as cocatalysts, and was amazingly improved, providing the greatest activity, using only triisobutyl aluminum (TIBA). We present a combination of ESR, C60 radical trapping, and MALDI-TOF studies describing the formation of the single-site active species, capturing some unique features of the complexes and shedding light on the polymerization mechanism.
authors.affiliation: Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa 32000, Israel.
authors.forename: Elena
authors.initials: E
authors.lastname: Domeshek
authors.forename: Rami J
authors.initials: RJ
authors.lastname: Batrice
authors.forename: Sinai
authors.initials: S
authors.lastname: Aharonovich
authors.forename: Boris
authors.initials: B
authors.lastname: Tumanskii
authors.forename: Mark
authors.initials: M
authors.lastname: Botoshansky
authors.forename: Moris S
authors.initials: MS
authors.lastname: Eisen
mesh_terms: D008671:Actinoid Series Elements / Q000737:chemistry*; D002384:Catalysis; D005030:Ethylenes / Q000737:chemistry*; D008094:Lithium / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D058105:Polymerization; D014501:Uranium / Q000737:chemistry*
chemical_list: D008671:Actinoid Series Elements; D005030:Ethylenes; D009942:Organometallic Compounds; C525037:triisobutylaluminum; D014501:Uranium; C036216:ethylene; D008094:Lithium