AN IMPROVED SYNTHESIS OF ETHYL 6-(BENZIMIDAZOL-2-YL) PYRIDINE-2-CARBOXYLATE AND APPLICATION OF ITS NICKEL COMPLEX TOWARDS ETHYLENE CATALYTIC BEHAVIOR
Ethyl 6-(benzimidazol-2-yl)-pyridine-2-carboxylate (EBIPC) was efficiently synthesized by condensation reaction of β-keto ester pyridine carboxylate and o-phenylenediamine. The compound was characterized by elemental analysis and spectroscopic techniques (IR and NMR) to confirm its molecular structure. This new protocol afforded a product with higher yield (65.1%) and reduced number of reaction steps. Upon activation with trimethylaluminum (Me3Al) as the co-catalyst, the nickel complexes exhibited high catalytic activities for ethylene oligomerization (up to 1.26 x 106 g mol-1(Ni) h-1). Various polymerization reaction conditions significantly influenced the catalytic properties of the complexes.
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