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• 420119-95-5 2,6-bis[1-((2-methyl-6-isopropylphenyl)imino)ethyl]pyridine 

Relevant academic research and scientific papers

Propylene polymerization with a bisiminepyridine iron complex: Activation with Ph3C [B(C6F5)4] and AlR3; iron hydride species in the catalytic cycle

The complex 2,6-bis [1-(2-isopropyl-6-methylphenylimino)ethyl]-pyridineiron(II)di chloride was used for propylene polymerization. Activation with Ph3C [B(C6F5)4] and subsequent treatment with triisobutylaluminum or triethylaluminum generated a very active polymerization catalyst for propylene. The activity was much higher than that obtained with methylaluminoxan (MAO) and even higher than using modified MAO. Detection of the propylene consumption with mass-flowmeters allowed the first view of the kinetic profile of propylene polymerization with this type of catalysts. Hydrogen addition to the polymerization led to higher activities and allowed formulation of a complete catalytic reaction cycle containing an iron hydride species. This cycle comprised one starting cycle and two propagation cycles, which could be controlled with the aluminumtrialkyl-propylene ratio.

Studies on the atropisomerism of Fe(II) 2,6-Bis(N-arylimino)pyridine complexes

NMR spectra of free 2,6-bis(N-arylimino)pyridine (PDI) ligands displaying different substituents at the ortho and ortho′ positions of the two N-aryl rings indicate that they can exist in syn (meso) and anti (chiral) configurations. These interconvert in solution at room temperature, via rotation of the aryl group. The corresponding paramagnetic FeX2(PDI) complexes exhibit the same kind of isomerism, a property that is thought to be important for their activity as R-olefin polymerization catalysts. For the first time, this has been detected by 1H NMR and studied in solution. Although the conformational stability of the diastereoisomeric complexes varies widely (depending on the size of the substituents at the imine and the aromatic rings), a moderate degree of steric hindrance suffices to allow their chemical separation. A simple procedure is developed for the preparation of these complexes in diastereoisomerically pure form. In addition, introduction of a prochiral substituent in the pyridine ring enables positive assignment of the stereoisomers. Isomerization rate measurements of the Fe(II) complexes in solution suggest that isomerization very likely involves the dissociation of the corresponding Fe-N(imino) bond prior to the rotation of N-aryl groups. DFT calculations provide additional support to the conformational assignment as well as the dissociative isomerization mechanism.

Separation of a diiminopyridine iron(II) complex into rac- and meso- diastereoisomers provides evidence for a dual stereoregulation mechanism in propene polymerization

Separation of a diiminopyridine iron(ii) complex into its rac- and meso- diastereoisomers provides for first time the opportunity of observing the enantiomorphic site control competing with the chain-end control mechanism in a non-metallocene catalyst system. The Royal Society of Chemistry.

Heterogenized iron(II) complexes as highly active ethene polymerization catalysts

The synthesis of new iron(II) diiminopyridine complexes and their heterogenization to give highly active ethene polymerization catalysts is described. The ligands are characterized by 1H NMR, 13C NMR spectroscopy and GC/MS. The compl