High-temperature catalysts for the production of α-olefins based on iron(II) and iron(III) tridentate bis(imino)pyridine complexes modified by nitrilo group

Autor: Tuyu Xie, Robert L. Waterland, Douglas J. Adelman, William J. Marshall, Rupert Spence, Brian M. Fish, Barbara Bobik Fones, Paul D. Soper, Alex Sergey Ionkin, Matthew F. Schiffhauer
Rok vydání: 2008
Předmět:
Zdroj: Journal of Polymer Science Part A: Polymer Chemistry. 46:585-611
ISSN: 1099-0518
0887-624X
DOI: 10.1002/pola.22408
Popis: Series of Fe(II) and Fe(III) tridentate bis(imino)pyridine complexes without nitrilo groups 2-6 and with nitrilo groups 7-13 were synthesized. According to X-ray analysis, the introduction of nitrilo groups in para- and ortho-positions tends to result in shorter axial Fe-N bonds. Both types of complexes, 2-6 and 9-13, afforded very productive catalysts for the production of α-olefins with higher K values and better linearity of Schultz-Flory distribution α-olefins than the parent methyl substituted Fe(II) complex 1. Noticeably, the complexes functionalized with a para-nitrilo group 9-13 tend to make α-olefins with higher K values of the Schultz-Flory distribution, more ideal distributions, and less of the heavier insoluble fractions of α-olefins than corresponding nonsymmetrically substituted complexes without para-nitrilo groups 2-6. Statistically significant correlations were obtained between % solids of total α-olefins and the blocked solid angle fraction in the +z hemisphere (R 2 adj == 51.3%, p = 0.012) and between catalyst productivity and total blocked solid angle fraction (R 2 adj = 43.5%, p = 0.023). The modest values of R 2 adj show that, while steric effects are significant, they are not the sole factor determining catalyst performance.
Databáze: OpenAIRE
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