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• 850583-55-0 (2-carbethoxy-6-[1-[(2,6-diethylphenyl)imino]-ethyl]pyridine) 

Relevant academic research and scientific papers

Preparation, structure and ethylene polymerization/oligomerization behavior of 2-carbethoxy-6-iminopyridine-based transition metal complexes

The synthesis, characterization and ethylene polymerization/oligomerization of a series of transition metal complexes with the formula {2-carbethoxy-6-[1-[(2,6-dimethylphenyl)imino]-ethyl]pyridine}nMCl2 [M = Mn(II) (8), Fe(II) (9), Co(II) (10), Cu(II) (11), Zn(II) (12), n = 1; Ni(II) (13), n = 2]; {2-carbethoxy-6-[1-[(2,4,6- trimethylphenyl)imino]ethyl]pyridine}MCl2 [M = Fe(II) (14), Co(II) (15), Ni(II) (16)]; {2-carbethoxy-6-[1-[(2,6-diethylphenyl)-imino]ethyl]pyridine}MCl2 [M = Fe(II) (17), Co(II) (18), Ni(II) (19)] have been reported. Systematic studies are focused on the relationship between the catalytic activity of these complexes for ethylene polymerization/oligomerization and the electronic property of the central metal, the ligand structure, as well as the reaction conditions. The Fe(II), Co(II), Ni(II) catalyst systems afford moderate activities ranging from 0.35 × 104 to 5.9 × 104 g/mol-Metal h atm, and the most active catalysts are those with two smaller substituents in the ortho-positions of the N-aryl ring. X-ray crystallographic analysis of complex 12 reveals a four-coordinated distorted tetrahedral geometry, while complex 18 indicates a five-coordinated distorted trigonal bipyramid, in which the tridentate ligand coordinates via weak bonding between the carbonyl oxygen of the ester group and cobalt.

Nickel (II) complexes bearing 2-ethylcarboxylate-6-iminopyridyl ligands: Synthesis, structures and their catalytic behavior for ethylene oligomerization and polymerization

A series of nickel (II) complexes (L)NiCl2 (7-9) and (L)NiBr2 (10-12) were prepared by the reactions of the corresponding 2-carboxylate-6-iminopyridine ligands 1-6 with NiCl2·6H 2O or (DME)NiBr2 (DME = 1,2-dimethoxyethane), respectively. All the complexes were characterized by IR spectroscopy and elemental analysis. Solid-state structures of 7, 8, 10, 11 and 12 were determined by X-ray diffraction. In the cases of 7, 8 and 10, the ligands chelate with the nickel centers in tridentate fashion in which the carbonyl oxygen atoms coordinate with the metal centers, while the carbonyl oxygen atoms are free from coordinating with the nickel centers in 11 and 12. Upon activation with methylaluminoxane (MAO), these complexes are active for ethylene oligomerization (up to 7.97 × 105 g mol-1 (Ni) h-1 for 11 with 2 equivalents of PPh3 as auxiliary ligand) and/or polymerization (1.37 × 104 g mol-1 (Ni) h-1 for 9). The ethylene oligomerization activities of 7-12 were significantly improved in the presence of PPh3 as auxiliary ligands. The effects of the coordination environment and reaction conditions on the ethylene catalytic behaviors have been discussed.