Abstract
The complex formation equilibria of the binary and ternary systems M(II)-Cephradine and M(II)-2,2-Bipyridyl-Cephradine were investigated by a potentiometric technique at 25 degrees C and an ionic strength of 0.1 M NaNO3 (M = Cu, Ni, Co, and Zn). The effect of dioxane as a solvent on the protonation constants of cephradine and the formation constants of the Cu-cephradine complex was studied. The relative stability of each ternary complex was compared with that of the corresponding binary complex in terms of Delta logK. The mode of ternary complex formation was ascertained by conductivity measurements. The copper(II), nickel(II), and cobalt(II) complexes of cephradine were synthesized and characterized by elemental analysis, conductivity measurements, and IR spectra.