264259-03-2Relevant academic research and scientific papers
2-Phosphanylphenolate Nickel Catalysts for the Polymerization of Ethylene
Heinicke, Joachim,Koehler, Martin,Peulecke, Normen,He, Mengzhen,Kindermann, Markus K.,Keim, Wilhelm,Fink, Gerhard
, p. 6093 - 6107 (2007/10/03)
The previously unknown methallylnickel 2-diorganophosphanylphenolates (R=Ph, cHex) were synthesized and found to catalyze the polymerization of ethylene. To explore the potential for ligand-tuning, a variety of P-alkyl- and P-phenyl-2-phosphanylphenols wa
Methyl(2-phosphanylphenolato[P,O])nickel(II) complexes - Synthesis, structure, and activity as ethene oligomerization catalysts
Heinicke, Joachim,He, Mengzhen,Dal, Attila,Klein, Hans-Friedrich,Hetche, Olaf,Keim, Wilhelm,Floerke, Ulrich,Haupt, Hans-Juergen
, p. 431 - 440 (2007/10/03)
Reactions of various substituted 2-phosphanylphenols 1a-f with half- molar amounts of cis-[MeNi(μ-OMe)(PMe3)]2 have been found to yield square- planar methyl(2-phosphanylphenolato)(trimethylphosphane)nickel(II) complexes 2a-f. 2J(PP) coupling constants of 305-316 Hz at low temperature indicate a trans-configuration for the products, while broad 31P-NMR signals at room temperature can be attributed to rapid dissociation of PMe3. Reaction with excess 1 gave rigid bis(2-phosphanylphenolato)nickel(II) complexes as exemplified by 3e, whereas addition of PMe3 to 2a led to the penta- coordinate methyl(2-phosphanylphenolato)bis(trimethylphosphane)nickel(II) complex 4a. Higher yields of 4a and 4d were obtained by reactions of 1a and 1d with Me2Ni(PMe3)3. Single-crystal X-ray diffraction analyses of 3e and 4a have revealed the structures as square-planar trans-bis- and trigonal- bipyramidal mono(2-phosphanylphenolato)nickel(II) P(intersection set)O- chelate complexes, respectively. The methylnickel complexes 2 and 4 have been found to be effective one-component catalysts for the oligomerization of ethene. High conversions (> 96%) were achieved with the P-basic derivatives 2e, 2f, and 4d bearing one or two branched alkyl groups (isopropyl, tert- butyl), whereas the diphenylphosphanyl derivatives were less active; 4d gave shorter oligomers than 2e or 2f.
