Síntese e caracterização de complexos diimínicos de níquel II

Abstract

The present work discusses the synthesis and characterization of three new Nickel (II) complexes containing ligands derived from Schiff Bases of the α-diimine class. The use of these compounds has shown to be highly active for olefin polymerization, presenting great academic and industrial interest. The synthetic route was carried out from reactions using nickel chloride hexahydrate (NiCl2.6H2O) and nickel (II) bis-(acetylacetonate) as precursors, N-N donor groups as ligands, and ethanol as solvent. The diimine ligands used in the synthesis of these complexes have methyl groups at the ortho and/or para positions of the aromatic rings, and are referred to as 2,4-Dime and 2,6-Dime. To verify the coordination of the ligand to the metal center and the chemical and physical phenomena that encompass the different techniques, the complexes were characterized from the techniques of absorption spectroscopy in the infrared region (IR), absorption spectroscopy in the ultraviolet/visible region (UV/vis), conductometry, cyclic voltammetry (CV) and nuclear magnetic resonance NMR of 1H and 13C.