Synthesis, APPI Mass-Spectrometric Characterization, and Polymerization Studies of Group 4 Dinuclear Bis(ansa-metallocene) Complexes

Catalysts

Mathilde Farenc¹  Carlos Afonso¹  Aurelien Vantomme²  Alexandre Welle²  Pierre Giusti³  Jean-Michel Brusson⁴  Leslie Bitard⁵  Jean-François Carpentier⁵  Evgueni Kirillov⁵  Gilles Schnee⁵ 

[1] CNRS, COBRA, Univ Rouen, UMR 6014, F-76821 Mont Saint Aignan, France;Total Research and Technologies Feluy, Zone Industrielle C, B-7181 Feluy, Belgium;Total Research and Technologies Gonfreville, BP 27, F-76700 Harfleur, France;Total SA, Direction scientifique, F-92069 Paris La Défense, France;Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes), UMR 6226, F-35000 Rennes, France;

关键词: metallocene catalysts;    mass-spectroscopy;    olefin polymerization;   

DOI  :  10.3390/catal8110558

来源: DOAJ

【 摘 要 】

New ligand platforms of the type p- or m-Ph{-CR(3,6-tBu₂Flu)(Cp)}₂ (para-, R = Me (2a), H (2b); meta-, R = Me (2c)) were synthesized via nucleophilic addition of the 3,6-tBu₂-fluorenyl-anion onto the parent phenylene-bridged difulvenes (1a⁻c). The corresponding discrete homodinuclear zirconium and hafnium bis(dichloro ansa-metallocene) complexes, Ph[{-CR(3,6-tBu₂Flu)(Cp)}MCl₂]₂ (p-, R = Me (3a-Zr₂, 3a-Hf₂), R = H (3b-Zr₂); m-, R = Me (3c-Zr₂), were prepared by salt metathesis reactions. An attempt to generate in situ a heterodinuclear complex 3a-Zr-Hf was also undertaken. For the first time, Atmospheric Pressure PhotoIonization (APPI) mass-spectrometric data were obtained for all dinuclear compounds and found to be in excellent agreement with the simulated ones. Preliminary studies on the catalytic performances of these dinuclear complexes, upon activation with MAO, in ethylene homopolymerization and ethylene/1-hexene copolymerization revealed a few differences as compared to those of the monometallic analogues. In particular, slightly lower molecular weights and a greater formation of short methyl and ethyl branches were obtained with the dinuclear systems.

【 授权许可】

Unknown