The basicity consts. of 1,4,8-triazaoctane (2,3-tri) were detd. in 0.5M KNO3 at 25.0° potentiometrically, using a glass electrode. The equil. between (2,3-tri) and Ni2+, Cu2+, Zn2+ ions were investigated under similar conditions. The stability consts. show that the complexes ML2+ with this unsym. ligand are more stable than the complexes with the sym. ligands: 1,4,7 triazaheptane and 1,5,9 triazanonane. This behavior seems to be due to the alleviation of the strain present in the complexes of the last 2 ligands. In addn. to the simple complexes ML2+ and ML22+, Cu2+ and Zn2+ give at high pH hydroxo complexes MLOH+. cu2+ and Ni2+ also form protonated complexes CuHL23+, and NiHL3+.
Size of the chelate rings and stability of some transition metal(II) ion complexes with linear aliphatic triamines. 1,4,8-Triazaoctane (2,3-tri)
FABBRIZZI, LUIGI;
1973-01-01
Abstract
The basicity consts. of 1,4,8-triazaoctane (2,3-tri) were detd. in 0.5M KNO3 at 25.0° potentiometrically, using a glass electrode. The equil. between (2,3-tri) and Ni2+, Cu2+, Zn2+ ions were investigated under similar conditions. The stability consts. show that the complexes ML2+ with this unsym. ligand are more stable than the complexes with the sym. ligands: 1,4,7 triazaheptane and 1,5,9 triazanonane. This behavior seems to be due to the alleviation of the strain present in the complexes of the last 2 ligands. In addn. to the simple complexes ML2+ and ML22+, Cu2+ and Zn2+ give at high pH hydroxo complexes MLOH+. cu2+ and Ni2+ also form protonated complexes CuHL23+, and NiHL3+.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
