Abstract
Symmetric and asymmetric Ni(II) diimine complexes such as 2-[(2,6-diisopropylphenylimino)methyl]pyridine nickel(II) dibromide (a), 2-[1-(2,6-diisopropylphenylimino)ethyl]pyridine nickel(II) dibromide (b) and [1,2-bis(2,6-diisopropylphenylimino)] acenaphthene nickel(II) dibromide (c) were synthesized. For olefin homopolymerization, asymmetric Ni(II) diimine complexes [(a) & (b)] were compared with symmetric system (c). Asymmetric Ni(II) diimine complexes exhibited less catalytic activity and thermal stability as well as more b-hydride elimination than a symmetric diimine complex (c). The activity of (a) was larger than that of (b), which indicates that methyl group has a contribution to the instability of catalyst by s bond vibration rather than the stabilization of the active site by electron releasing property.
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This paper is dedicated to Professor Wha Young Lee on the occasion of his retirement from Seoul National University.
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Seo, T.S., Hong, D.S., Jung, D.W. et al. Olefin homopolymerization catalyzed over asymmetric and symmetric ni(II) diimine complexes. Korean J. Chem. Eng. 19, 622–626 (2002). https://doi.org/10.1007/BF02699307
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DOI: https://doi.org/10.1007/BF02699307