The effect of 2,2′-bipyridyl on the stability of Cu(II) complexes with carboxylic acids

The stability constants β₂, and β₂ of simple Cu(II) complexes with methoxyacetic, phenylacetic, and cyclohexylacetic acid were determined spectrophotometrically and compared with the stability of composite complexes containing 2,2′-bipyridyl as the first ligand and the above mentioned acid as the second ligand. In each case the stability of the composite complex Cu(bip)L⁺ was found to exceed that of the simple complex CuL⁺ and the differences in the values of log β are comprised within 0.15–0.17.