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

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