Zirconocene compounds derived from boratastilbene, 4-boratastyrylstilbene, and 1,4-bis(boratastyryl)benzene and their reactivities to the ethylene polymerization

摘要

(eta(6) -Boratastilbene)(eta(5)-pentamethylcyclopentadienyl)zirconium dichloride (1), (eta(6)-4-boratastyryistilbene)(eta5-pentamethylcyclopentadienyl)zirconium dichloride (2), [1,4-bis(boratastyryl)benzene]bis[(dichloro)(pentamethylcyclopentadienyl)z irconium] (3), and bis(eta(6)-boratastilbene)zirconium dichloride (4) were synthesized. The crystal structure of 1 was determined by X-ray crystallography, These zirconium complexes show activities in the presence of methylaluminoxane (MAO) for the polymerization of ethylene. The activities are in the following order: 1 > 2 > Cp2ZrCl2 > 3 > 4. The activity of I is three times higher than that Of Cp2ZrCl2 under similar conditions. (C) 2002 Elsevier Science B.V. All rights reserved. [References: 27]