Synthesis and characterization of para-nitro substituted 2,6-bis(phenylimino)pyridyl Fe(II) and Co(II) complexes and their ethylene polymerization properties

Zerong Long, Biao Wu*, Peiju Yang, Gang Li, Yanyan Liu, Xiao Juan Yang

*此作品的通讯作者

科研成果: 期刊稿件文章同行评审

28 引用 (Scopus)

摘要

Four iron(II) and cobalt(II) complexes ligated by 2,6-bis(4-nitro-2,6-R2-phenylimino)pyridines, LMCl2 (1: R = Me, M = Fe; 2: R = iPr, M = Fe; 3: R = Me, M = Co; 4: R = iPr, M = Co) have been synthesized and fully characterized, and their catalytic ethylene polymerization properties have been investigated. Among these complexes, the iron(II) pre-catalyst bearing the ortho-isopropyl groups (complex 2) exhibited higher activities and produced higher molecular weight polymers than the other complexes in the presence of methylaluminoxane (MAO). A comparison of 2 with the reference non-nitro-substituted catalyst (2,6-bis(2,6-diisopropylphenylimino)pyridyl)FeCl2 (FeCat 5) revealed a modest increase of the catalytic activity and longer lifetime upon substitution of the para-positions with nitro groups (activity up to 6.0 × 103 kg mol-1 h-1 bar-1 for 2 and 4.8 × 103 kg mol-1 h-1 bar-1 for 5), converting ethylene to highly linear polyethylenes with a unimodal molecular weight distribution around 456.4 kg mol-1. However, the iron(II) pre-catalyst 1 on changing from ortho-isopropyl to methyl groups displayed much lower activities (over an order of magnitude) than 2 under mild conditions. As expected, the cobalt analogues showed relatively low polymerization activities.

源语言英语
页(从-至)3793-3799
页数7
期刊Journal of Organometallic Chemistry
694
23
DOI
出版状态已出版 - 1 11月 2009
已对外发布

指纹

探究 'Synthesis and characterization of para-nitro substituted 2,6-bis(phenylimino)pyridyl Fe(II) and Co(II) complexes and their ethylene polymerization properties' 的科研主题。它们共同构成独一无二的指纹。

引用此

Long, Z., Wu, B., Yang, P., Li, G., Liu, Y., & Yang, X. J. (2009). Synthesis and characterization of para-nitro substituted 2,6-bis(phenylimino)pyridyl Fe(II) and Co(II) complexes and their ethylene polymerization properties. Journal of Organometallic Chemistry, 694(23), 3793-3799. https://doi.org/10.1016/j.jorganchem.2009.07.027