PMID- 14679521
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20040928
LR  - 20090804
IS  - 0947-6539 (Print)
IS  - 0947-6539 (Linking)
VI  - 9
IP  - 24
DP  - 2003 Dec 15
TI  - 2-phosphanylphenolate nickel catalysts for the polymerization of ethylene.
PG  - 6093-107
AB  - 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 was synthesized and allowed to react with 
      [Ni(cod)(2)] (cod=1,5-cyclooctadiene) or with NiBr(2).DME and NaH. The complexes 
      formed in situ with [Ni(cod)(2)] are generally active as ethylene polymerization 
      catalysts with all the ligands tested, whereas the latter systems are inactive 
      when 2-dialkylphosphanylphenols are applied. M(w) values, ranging from about 1000 
      to about 100000 g mol(-1), increase for various R(2)P groups in the order R=Ph<Et 
      approximately tBu<iPr<cHex, while aryloxy substituents usually diminish the 
      molecular weights. Increasing basicity of P- or aryloxy substituents usually 
      leads to increasing turnover numbers. The polymers are high density polyethylene 
      (HDPE) with low methyl and sometimes low long-chain branching. Investigation of 
      the influence of the solvent shows that the catalysts are stabilized by some 
      oxygen-containing Lewis bases as well as by olefins. The catalysts are tolerant 
      to water, in particular the 2-dicyclohexylphosphanylphenolate nickel catalyst, 
      which in THF-water (1:1) gives HDPE with M(w)=39000, M(n)=14500 g mol(-1). 
      Additives of tetrahydrothiophene or pyridine do not inhibit the catalyst, but 
      decrease the reaction rate and the molecular weight of the polymers.
FAU - Heinicke, Joachim
AU  - Heinicke J
AD  - Institut fur Chemie und Biochemie, Ernst-Moritz-Arndt-Universitat Greifswald, 
      Soldmannstrasse 16, 17487 Greifswald, Germany. heinicke@uni-greifswald.de
FAU - Kohler, Martin
AU  - Kohler M
FAU - Peulecke, Normen
AU  - Peulecke N
FAU - He, Mengzhen
AU  - He M
FAU - Kindermann, Markus K
AU  - Kindermann MK
FAU - Keim, Wilhelm
AU  - Keim W
FAU - Fink, Gerhard
AU  - Fink G
LA  - eng
PT  - Journal Article
PL  - Germany
TA  - Chemistry
JT  - Chemistry (Weinheim an der Bergstrasse, Germany)
JID - 9513783
EDAT- 2003/12/18 05:00
MHDA- 2003/12/18 05:01
CRDT- 2003/12/18 05:00
PHST- 2003/12/18 05:00 [pubmed]
PHST- 2003/12/18 05:01 [medline]
PHST- 2003/12/18 05:00 [entrez]
AID - 10.1002/chem.200304888 [doi]
PST - ppublish
SO  - Chemistry. 2003 Dec 15;9(24):6093-107. doi: 10.1002/chem.200304888.