863029-58-7Relevant academic research and scientific papers
Vinyl polymerization of norbornene on nickel complexes with bis(imino)pyridine ligands containing electron-withdrawing groups
Antonov, Artem A.,Semikolenova, Nina V.,Zakharov, Vladimir A.,Zhang, Wenjuan,Wang, Youhong,Sun, Wen-Hua,Talsi, Evgenii P.,Bryliakov, Konstantin P.
experimental part, p. 1143 - 1149 (2012/04/10)
A series of novel bis(imino)pyridine nickel(II) dichloride complexes, with the bis(imino)pyridine ligands containing electron-withdrawing groups (F, Cl, Br, CF3), have been prepared and characterized by elemental analysis and NMR spectroscopy. All complexes exhibit paramagnetically shifted 1H NMR spectra, indicative of the high-spin (S = 1) state of the d8 nickel(II) central atom. These complexes have been found to be highly active catalysts of vinyl-type norbornene polymerization upon activation with MAO, displaying activities up to 1.16 × 107 g of PNB (mol of cat.)-1 h-1 (the highest ever reported for norbornene polymerizations on bis(imino)pyridine nickel complexes) and yielding high-molecular-weight polynorbornene (Mw up to 4.5 × 10 6). X-ray structures for some of the nickel complexes are reported.
