Makhosonke Ngcobo, G. S. Nyamato, S. O. Ojwach
Nov 1, 2019
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0
Influential Citations
13
Citations
Journal
Molecular Catalysis
Abstract
Abstract Reactions of 2-[(2-hydroxyethyl)imino]methyl]phenol (L1H), 2-[1-[(2-hydroxyethyl)imino]ethyl]phenol (L2H) and 2-[{[(2-diethylamino)ethyl]imino}methyl]phenol (L3H) with CoCl2 and FeCl2 salts produced the metal complexes [Co(L1)2] (Co1), [Fe(L1)2] (Fe1), [Co(L2)2] (Co2), [Fe(L)2] (Fe2), [Co2(L3H)2Cl4)] (Co3) and [Fe2(L3H)2Cl4] (Fe3), respectively. Molecular structureof Fe1 confirmed the formation of mononuclear complex containing two tridentate bound anionic ligand L1. On the other hand, the solid state structure of Co3 established the formation of a dinuclear complex bearing a bidentate zwitterionic ligand L3H. Activation of the Fe(II) and Co(II) complexes with EtAlCl2 or MAO co-catalysts, gave active catalysts in oligomerization of ethylene to give C4 and C6 oligomers. Generally, the Co(II) complexes exhibited higher catalytic activities than their Fe(II) analogues. While activation with MAO produced mainly C4 oligomers (96%), EtAlCl2 gave predominantly C6 oligomers. Density functional theory data provided insights on the catalytic activity trends and effect of complex/ligand structure on the ethylene oligomerization reactions.