797009-62-2Relevant academic research and scientific papers
Control of symmetry in active cationic ansa-zirconocene species: Catalyst preparation, characterization and ethylene-norbornene copolymerization
Lee, Hyosun,Hong, Sung-Don,Park, Young-Whan,Jeong, Boong-Goon,Nam, Dae-Woo,Jung, Hye Young,Jung, Min Whan,Song, Kwang Ho
, p. 3402 - 3411 (2004)
New bis-hydrocarbyl complexes of methylene bridged ansa-metallocenes [H2Me2H2)2]ZrR2 {R = Me (1), CH2Ph (2), CH2SiMe3 (3), Ph (4)} have been prepared. They form catalytically active intermediates with borane or borate depending on solvent and Zr-R group. Specifically, [H2C(Me2C5H2)2] Zr(CH2Ph)2 (2) produced an ion pair upon treatment with B(C6F5)3 whereas [H2 C(Me2C5H2)2]Zr(CH2 SiMe3)2 (3) produced a zwitterionic species, identified by 1H,13C, and 19F NMR spectroscopy. Copolymerization of ethylene and norbornene for the metallocene dichloride/MAO and bis-hydrocarbyl complex/borate systems was compared.
