| Abstract: Three polyamino-polyamide ligands 1,12-bis((α-hydroxylmethyl)phenyl)-2,5,8,11-tetraazadodecane-1,12-dione (L1), 1,13-bis((α-hydroxylmethyl)phenyl)-2,5,9,12-tetraazatridecane-1,13- dione (L2), 1,15-bis ((α-hydroxylmethyl)phenyl)-2,5,8,11,14-pentaazapentadecane-1,15-dione (L3) have been synthesized. The stability constants of complexation of Cu(Ⅱ) with these three ligands in dioxane/water (V/V, 15/85) mixed solvent have been determined by pH titrations at 5.0 ℃, 15.0 ℃, 25.0 ℃ and 35.0 ℃ respectively. The thermodynamic parameters ΔHm? and ΔSm? were obtained. The result shows that both the protonation of the ligands and the formation of metal complexes are controlled by the change of enthalpy. In addition, the stability constants of ternary complexes of Cu(Ⅱ), L and α-amino-acid (AA) have been determined at 25.0 ℃, where L=L1，L2 and L3, AA = L-proline (Pro), L-isoleucine (Ile), L-valine (Val), glycine (Gly), L-serine (Ser), respectively. It is observed that linear free energy relationship (LFER) exists in the ternary systems. |
