Complexes with macrocyclic ligands, VIII. Stability of the Cu(II) complexes with 1,4,7-triazacyclodecane and 1,5,9-triazacyclododecane

Abstract

The potentiometric and spectrophotometric study of the complexation of the title compounds (L) with Cu(II) has shown that CuL²⁺, CuL₂²⁺ and (CuLOH)₂²⁺ are the species present in solution.

Their stability constants at 25 °C and I = 0.5 and their spectral properties are given in Table 1 and 2, respectively. The results of both techniques indicate that all three amino groups of the ligand are involved in bonding, which is possible only if facial co-ordination in octahedral geometry occurs.