2-(1-(2-Benzhydrylnaphthylimino)ethyl)pyridylnickel halides: Synthesis, characterization, and ethylene polymerization behavior

Yue, Erlin; Zhang, Liping; Xing, Qifeng; Cao, Xiao-Ping; Hao, Xiang; Redshaw, Carl; Sun, Wen-Hua

Abstract

A series of 2-(1-(2-benzhydrylnaphthylimino)ethyl)pyridine derivatives (L1–L3) was synthesized and fully characterized. The organic compounds acted as bi-dentate ligands on reacting with nickel halides to afford two kinds of nickel complexes, either mononuclear bis-ligated L₂NiBr₂ (Ni1–Ni3) or chloro-bridged dinuclear L₂Ni₂Cl₄ (Ni4–Ni6) complexes. The nickel complexes were fully characterized, and the single crystal X-ray diffraction revealed for Ni2, a distorted square pyramidal geometry at nickel comprising four nitrogens of two ligands and one bromide; whereas for Ni4, a centrosymmetric dimer possessing a distorted octahedral geometry at nickel was formed by two nitrogens of one ligand, two bridging chlorides and one terminal chloride along with oxygen from methanol (solvent). When activated with diethylaluminium chloride (Et₂AlCl), all nickel complexes performed with high activities (up to 1.22 × 10⁷ g (PE) mol⁻¹(Ni) h⁻¹) towards ethylene polymerization; the obtained polyethylene possessed high branching, low molecular weight and narrow polydispersity, suggestive of a single-site active species. The effect of the polymerization parameters, including the nature of the ligands/halides on the catalytic performance is discussed.

Citation

Yue, E., Zhang, L., Xing, Q., Cao, X.-P., Hao, X., Redshaw, C., & Sun, W.-H. (2014). 2-(1-(2-Benzhydrylnaphthylimino)ethyl)pyridylnickel halides: Synthesis, characterization, and ethylene polymerization behavior. Dalton Transactions : an international journal of inorganic chemistry, 43(2), 423-431. https://doi.org/10.1039/c3dt52234b

• Journal Article Type: Article
• Acceptance Date: Sep 25, 2013
• Online Publication Date: Sep 25, 2013
• Publication Date: Jan 14, 2014
• Deposit Date: Jun 9, 2015
• Publicly Available Date: Jun 9, 2015
• Journal: Dalton transactions
• Print ISSN: 1477-9226
• Electronic ISSN: 1477-9234
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 43
• Issue: 2
• Pages: 423-431
• DOI: https://doi.org/10.1039/c3dt52234b
• Keywords: Ethylene polymerization; Nickel complexes; Polyethylene
• Public URL: https://hull-repository.worktribe.com/output/375002
• Publisher URL: http://pubs.rsc.org/en/content/articlelanding/2014/dt/c3dt52234b#!divAbstract
• Additional Information: Copy of article first published in: Dalton transactions, 2014, v.43, issue 2.
• Contract Date: Jun 9, 2015