Vanadium-based pro-catalysts bearing depleted 1,3-calix[4]arenes for ethylene or ε-caprolactone polymerization

Clowes, Lucy; Redshaw, Carl; Hughes, David L.

Abstract

Reaction of [V(X)(OR)3] (X = O, Np-tolyl, R = nPr, tBu) with 5,11,17,23-tBu-25,27-dihydroxycalix[4]arene (LH2) led to the formation of [V(X)(OR)L]2 X = O, R = nPr (1); X = Np-tolyl, R = nPr (2); X = Np-tolyl, R = tBu (3) as the major product. In the case of X = O, the minor hydrolysis product {[VO(OnPr)]2(μ-O)L}2 (4) has also been characterized. Complexes (1)-(4), in the presence of the co-catalyst dimethylaluminum chloride and the reactivator ethyltrichloroacetate, are highly active (≥16,400 g/mmol h bar), thermally stable pro-catalysts for the polymerization of ethylene. The use of silica supports with (1) and (2) under slurry conditions yielded polymer with activities ≥30 g/mmol h. Complexes (1)-(3) have also been screened as pro-catalysts for the ring-opening polymerization of ε-caprolactone; the conversion rate order (1) (94%) > (2) (46%) > (3) (20%) was observed at 80 °C over 72 h. © 2011 American Chemical Society.

Citation

Clowes, L., Redshaw, C., & Hughes, D. L. (2011). Vanadium-based pro-catalysts bearing depleted 1,3-calix[4]arenes for ethylene or ε-caprolactone polymerization. Inorganic chemistry, 50(16), 7838-7845. https://doi.org/10.1021/ic2010198

• Journal Article Type: Article
• Online Publication Date: Jul 12, 2011
• Publication Date: Aug 15, 2011
• Deposit Date: Jun 8, 2022
• Journal: Inorganic Chemistry
• Print ISSN: 0020-1669
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 50
• Issue: 16
• Pages: 7838-7845
• DOI: https://doi.org/10.1021/ic2010198
• Public URL: https://hull-repository.worktribe.com/output/3622403