Organonickel(II) complexes with anionic tridentate 1, 3-bis(azolylmethyl)phenyl ligands. synthesis, structural characterization and catalytic behavior

John Hurtado, Andrés Ibañez, René Rojas, Mauricio Valderrama, Roland Fröhlich
2011 Journal of the Brazilian Chemical Society  
A reação de 2-bromo-1,3-bis(bromometil)benzeno com 3,5-dimetilpirazol e 1H-indazol produz os ligantes tridentados 2-bromo-1,3-bis(3,5-dimetilpirazol-1-ilmetil)benzeno (1) e 2-bromo-1,3bis(indazol-2-ilmetil)benzeno (2). Estes compostos reagem com [Ni(cod) 2 ] em tetraidrofurano (thf) para formar os complexos de adição oxidativa [NiBr{1,3-bis(azolilmetil)fenil-N,C,N}], azol = 3,5-dimetilpirazol (3) e indazol (4), os quais foram isolados em bons rendimentos como sólidos amarelos estáveis e
more » ... estáveis e caracterizados por meio de análise elementar, espectroscopia de absorção no infravermelho com transformada de Fourier (FTIR), espectrometria de massa e ressonância magnética nuclear (NMR). Adicionalmente, as estruturas moleculares de 2 e 4 foram determinadas por difratometria de raios X de monocristal. O complexo 4 foi testado como catalisador na reação de polimerização de etileno. The reaction of 2-bromo-1,3-bis(bromomethyl)benzene with 3,5-dimethylpyrazole and 1H-indazole yields the tridentate ligands 2-bromo-1,3-bis(3,5-dimethylpirazol-1-ylmethyl)benzene (1) and 2-bromo-1,3-bis(indazol-2-ylmethyl)benzene (2). These compounds react with [Ni(cod) 2 ] in tetrahydrofuran (thf) to form the oxidative addition complexes [NiBr{1,3-bis(azolylmethyl)phenyl-N,C,N}], azol = 3,5-dimethylpyrazol (3), indazol (4), which were isolated in good yields as stable yellow solids and characterized by elemental analysis, Fourier-transform infrared spectroscopy (FTIR), mass spectroscopy and nuclear magnetic resonance (NMR). In addition, the molecular structures of 2 and 4 were determined by single-crystal X-ray diffraction analysis. Complex 4 was tested as a catalyst in ethylene polymerization reaction.
doi:10.1590/s0103-50532011000900018 fatcat:pc76zpegafhk5monnhcsss5hky