Synthesis and Physicochemical Studies of Nickel(II) Complexes of Various 2-Alkyl-1-phenyl-1,3-butanediones and Their 2,2?-Bipyridine and 1,10-Phenanthroline Adducts

Joseph Woods,Helen Oluwatola Omoregie

doi:10.5539/ijc.v3n1p24

Abstract

Some 2-substituted-1-phenyl-1,3-butanedionato nickel(II) complexes and their 2,2′-bipyridine (bipy) and1,10-phenanthroline (phen) adducts have been synthesized and characterized by elemental analyses, infrared,electronic spectral studies, conductance, and magnetic susceptibility measurements. The electronic spectral datahave been interpreted in terms of the π3→π4* and other transitions and the effect of the substituents at β-position onthe different transitions determined. The infrared spectra of the nickel(II) complexes showed that the frequencies ofthe asymmetric C=O + C=C stretching vibrations were lowered from their ligand values.

Highlights

The authors are grateful to Third World Organization for Women in Science and Department of Chemistry University of Ibadan, Nigeria for the fellowship awarded and the provision of chemicals and solvents respectively
Thermal transfer printing materials containing metal β-diketonates exhibit good whiteness and image stability (Miura et al, 1993) and it has been found that toner containing metal complexes of β-diketones are stable, controllable and capable of producing clear colour images even at high temperature and high humidity without producing copier stain (Hiroshi and Katsuhiko, 1987)
In continuation of our studies on β-diketones and their derivatives (Woods et al, 2009a; Woods et al, 2009b), we report the results of our investigations on bis (2-substituted-1-phenyl-1,3-butanedionato) nickel(II) complexes Ni(R-bzac)2 (R = H, Me, Et, n-Pr, i-Pr and n-Bu) and their adducts with 2,2′-bipyridine and 1,10-phenanthroline

Summary

Preparation of the Ligands

The 2-alkyl-1-phenyl-1,3-butanediones were prepared according to a literature procedure (Patel and Woods, 1990). 3 mL 2-Me-1-phenyl-1,3-butanedione(3.39 g, 19.2 mmol) dissolved in 10 mL methanol was added to nickel(II) chloride hexahydrate (2.28 g, 9.60 mmol) in 3 mL water, while stirring and the pH was raised to 8. The Precipitated solids were washed with 40% methanol and dried over silica gel. Similar procedure was used for preparation of the other nickel(II) complexes. The 2,2′-bipyridine adduct of Ni(Me-bzac)2.2H2O was prepared by mixing 1.2 mL Me-bzacH (1.25 g, 7.07 mmol) and 2,2′-bipyridine (0.55 g, 3.53 mmol) in 80 mL methanol. The precipitates obtained were filtered, washed with few drops of acetone and dried in vacuo. Similar procedure was used for preparation of the other 2,2′-bipyridine and 1,10-phenanthroline adducts except 2,2′-bipyridine and 1,10-phenanthroline adducts of Ni(bzac)2.2H2O which were prepared by mixing the base with the complex prior to dissolution in the solvent

Physical Measurements

Results and Discussion

Conclusion