Synthesis and physico-chemical characterization of zinc(II), nickel(II) and cobalt(II) complexes with 2-phenyl-2-imidazoline

Abstract

Chlorides and nitrates of zinc(II), nickel(II) and cobalt(II) react with 2-phenyl-2-imidazoline to give complexes of the type [ML2X2]?nH2O (M=Zn, Ni or Co; L=2-phenyl-2-imidazoline; X=Cl or NO3; n=0, 1 or 2). The complexes were synthesized and characterized by elemental analysis of the metal molar conductivity, magnetic susceptibility measurements and IR spectra. The molar conductances of the zinc(II) complexes in DMF solutions indicate that the complexes behave as non-electrolytes. The values of magnetic conductivity in the case of nickel(II) complexes indicate that one of the coordinated anions (chloride or nitrate) has been replaced by DMF molecule. The molar conductivity values of cobalt(II) complexes indicate the partial substitution of coordinated anions with solvent molecules. The room temperature effective magnetic moments and IR data of the complexes suggest that all Zn(II), Ni(II) and Co(II) complexes have a tetrahedral configuration, which is realized by participation of the pyridine nitrogen of two organic ligand molecules, and two chloride or nitrate anions typical for these classes of organic ligands.Hloridi i nitrati cinka(II), nikla(II) kobalta(II) reaguju sa 2-fenil-2-imidazolinom dajuci komplekse tipa [ML2X2]?(H2O)n (M=Zn, Ni ili Co; L=2-fenil-2-imidazolin; X=Cl ili NO3; n=0, 1 ili 2). Kompleksi su sintetisani i okarakterisani elementarnom analizom metala, magnetnim i konduktometrijskim merenjima i IR spektrima. Vrlo niske vrednosti molarne provodljivosti za komplekse cinka(II) u DMF ukazuju na neelektrolitne karakteristike DMF rastvora kompleksa. Na osnovu vrednosti molarne provodljivosti za kompleks nikla(II) izvodi se zakljucak da je jedan od koordinovanih anjona (hloridni ili nitratni) zamenjen molekulom rastvaraca. Uvecane vrednosti molarne provodljivosti za komplekse kobalta(II) u odnosu na komplekse tipa neelektrolita su znatno manje od molarnih provodljivosti za komplekse elektrolita tipa 1:1 i ukazuju na parcijalnu zamenu koordinovanih hloridnih ili nitratnih jona molekulima rastvaraca. Na osnovu vrednosti magnetnih momenata i IR spektara izolovanih kompleksa cinka(II) nikla(II) i kobalta(II) moze se pretpostaviti da ispitivani kompleksi imaju tetraedarsku strukturu koja se realizuje monodentatnom koordinacijom dva molekula liganda preko piridinskog atoma azota i koordinacijom dva hloridna ili nitratna jona.