706788-83-2Relevant academic research and scientific papers
Nickel complexes bearing new P,N-phosphinopyridine ligands for the catalytic oligomerization of ethylene
Speiser, Fredy,Braunstein, Pierre,Saussine, Lucien
, p. 2633 - 2640 (2004)
The new phosphinopyridine ligands 2-[(diphenylphosphanyl)methyl]-6- phenylpyridine (5), 2-(2,6-dimethylphenyl)-6-[(diphenylphosphanyl)methyl] pyridine(6), 2-(2,6-diisopropylphenyl)6-[(diphenylphosphanyl)methyl]pyridine (7), and 2-[2-(diphenylphosphanyl)phenyl]-6-methylpyridine (8) have ben prepared in order to compare the influence of their stereoelectronic properties on the catalytic behavior of their respective mononuclear [NiCl2(P,N)] complexes 9-12. These Ni(II) complexes are paramagnetic in solution, as determined by the Evans method. Whereas they were inactive for the oligomerization of ethylene in the presence of methylalumoxane (MAO), they provided activities up to 61 000 mol of C2H4/((mol of Ni) h) (11) in the presence of only 6 equiv of AlEtCl2. The selectivities for C4 olefins were as high as 92% (12 with 2 equiv of AlEtCl a).
