Electronic Influence of the Thienyl Sulfur Atom on the Oligomerization of Ethylene by Cobalt(II) 6-(Thienyl)-2-(imino)pyridine Catalysis
Citations Over TimeTop 10% of 2007 papers
Abstract
The position of the sulfur atom in the thienyl group of 6-(thienyl)-2-(imino)pyridine ligands strongly affects the catalytic activity of the corresponding tetrahedral high-spin dihalide CoII complexes in the oligomerization of ethylene to α-olefins upon activation with methylaluminoxane (MAO). Complexes with the sulfur atom in the 3-position of the thienyl ring catalyze the selective conversion of ethylene to 1-butene, while catalysts containing thien-2-yl groups give C4−C14 α-olefins. In situ EPR experiments showed the occurrence of a spin state changeover with the formation of low-spin CoII species upon activation of the catalyst precursors by MAO. DFT calculations suggest that only thien-2-yl rings allow for the coordination of the sulfur atom to the cobalt center in the MAO-activated systems.
Related Papers
- → Synthesis, characterization, and catalytic behaviours of β-carbonylenamine-derived [O−NS]TiCl3 complexes in ethylene homo- and copolymerization(2009)46 cited
- → 2-(1-Aryliminopropylidene)quinolylcobalt(ii) dichlorides: synthesis, characterization and catalytic behaviour towards ethylene(2011)16 cited
- → Effect of Free Trimethylaluminum Content in Methylaluminoxane on Performances of Bis(salicylaldiminate)nickel(II)‐Based Catalysts for Ethylene Polymerization(2005)14 cited
- → Effect of trimethylaluminum on the polymerization of ethylene with the catalytic system Bis[N-(3,5-di-tert-butylsalicylidene)-2,3,5,6-tetrafluoroanilinato]titanium(IV) dichloride-methylaluminoxane(2010)3 cited
- Ethylene polymerization using butyl modified methylaluminoxane as cocatalyst(2005)