Fredy Speiser, P. Braunstein, L. Saussine
Apr 23, 2004
Citations
0
Influential Citations
74
Citations
Quality indicators
Journal
Organometallics
Abstract
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 AlEtCl2).