Synthesis, characterization and catalytic activity of the complex titanium bis(dimethylmalonate)-bis(diethylamido) in the polymerization of propylene

Tal Gueta-Neyroud, Boris Tumanskii, Mark Botoshansky, Moris S. Eisen*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

11 Scopus citations

Abstract

In this account we present the synthesis, characterization and catalytic activity in the polymerization of propylene of a bis(dimethyl malonate) titanium bis(diethylamine) complex (1). The complex exhibits in solution a dynamical isomerization following an internal Bailar twist. The activation of complex 1 was obtained by its reaction with methylalumoxane (MAO). The activated complex in solution shows a different dynamic process involving an equilibrium between a monodentate η1 and bidentate η2 binding of the dimethylmalonate ligand to the metal center. This equilibrium is responsible for the formation of, at least, two active species for the polymerization reaction bearing major symmetry differences. The monodentate coordination (opened form) of the ligand was found to be the major form of the active species of the complex when activated with MAO, most probably due to a strong interaction of the oxygen atoms in the ligand with the strong Lewis acid co-catalyst. The active species in the polymerization were studied by NMR and ESR spectroscopies. The resulting polypropylene showed elastomeric properties with low tacticites.

Original languageEnglish
Pages (from-to)927-939
Number of pages13
JournalJournal of Organometallic Chemistry
Volume692
Issue number5
DOIs
StatePublished - 1 Feb 2007
Externally publishedYes

Keywords

  • Catalysis
  • Dimethylmalonate
  • Elastomeric propylene
  • Group 4
  • Polymerization
  • Titanium
  • Ziegler-Natta

Fingerprint Dive into the research topics of 'Synthesis, characterization and catalytic activity of the complex titanium bis(dimethylmalonate)-bis(diethylamido) in the polymerization of propylene'. Together they form a unique fingerprint.

Cite this