Coordination modes of histidine- or methioninehydroxamic acids in copper(II) mixed-ligand complexes with ethylenediamine in aqueous solution

Stabilities and Coordination Modes of α-Alaninephosphonic Acid in Copper(II) Heteroligand Complexes with Ethylenediamine, Diethylenetriamine or N,N,N′,N′,N″-Pentamethyldiethylene Triamine in Aqueous Solution

“…The detailed discussions about the acid-base properties of these ligands can be found in earlier papers [6][7][8][9][10][11][12][13]. The results for the binary systems Cu 2+ -en [14][15][16][17][18], Cu 2+ -dien [5,6,[17][18][19], Cu 2+ -Me 5 dien [15,20,21] and Cu 2+ -α-Ala(P) [22,23] are in good agreement with the literature data.…”

“…The values of log 10 K, close to −1, were obtained earlier for heteroligand species of tetragonal geometry formed by ethylenediamine and glycinephosphonic acid [1], aminoacids [22,23] or aminohydroxamic acids in the copper(II) solution [8]. Distinctly lower values of log 10 K are observed in the case of heteroligand complexes [Cu(L 1 )(α-Ala(P))] with dien or Me 5 dien (Table 1, row 6).…”

“…Up to this pH only simple species of en or α-Ala(P) are formed. The EPR parameters of the spectra observed at this pH in the liquid and frozen solution (g iso = 2.134, A iso = 68 × 10 −4 cm −1 , g = 2.282, A = 182 × 10 −4 cm −1 ) are very similar to those reported for the Cu 2+ -en binary system in an acid solution [8], what confirms that [Cu(en)] 2+ dominates. As the pH of the solution increases up to pH = 6, the spectrum changes distinctly.…”

Stabilities and coordination modes of glycinephosphonic acid in copper(II) heteroligand complexes with ethylenediamine, diethylenetriamine or N,N,N′,N′,N″-pentamethyldiethylene triamine in aqueous solution

“…The detailed discussion about the acid-base properties of these ligands can be found in the early articles [20,24,25,[31][32][33]. The obtained results for the binary systems Cu 2?…”

“…Heteroligand metal(II) complexes in which aliphatic polyamines play a role as a primary ligand and aminohydroxamic acid as a secondary one have been studied by us since 1995 [18][19][20][21][22][23][24][25][26]. Now we are interested in ternary systems with the same polyamines but in which the secondary ligand is aminophosphonic acid.…”