Studies on Y(III), La(III), Ce(III), Pr(III), Nd(III) and Sm(III) complexes of some hydroxy naphthoic acids

Transition Metal Complexes of 3,5-Dihydroxy-2-naphthoic Acid and its Nano Metal Oxides: Synthesis and Characterization

“…Lanthanide complexes [5,6] with ortho substituted naphthoic acid show that the hydroxynaphthoate ion is monodentate, coordinated to the metal through the carboxyl group. A study of (µ-L) 4[Nd(H2O)(EtOH)L]2·2H2O·2EtOH, (L is 1-hydroxy-2-naphthoate ligand) indicates that, two ligands act as bidentates and the two other as terdentates [7].…”

Formation Constants of Chromium(III), Scandium(III) and Yttrium(III) Complexes of Some Hydroxy Naphthoic Acids

“…They obtained the stability constants of binary complexes of Sc(III) with 1,2-HNA and 3,2-HNA only at an ionic strength of 0.1 M KNO 3 in 50% (v/v) aqueous-ethanol medium by the average value method. 29,30) Y(III) and lanthanides formed with 2-hydroxy-3-naphthoic acid (2,3-HNA), 2-hydroxy-1-naphthoic acid (2,1-HNA) and 1,2-HNA were also investigated by Bhatt et al 14) and Deshpande et al 15) They applied only the Calvin-Bjerrum potentiometric titration technique at 25°C and 0.1 M NaClO 4 ionic strength in 75% dioxane-25% (v/v) water medium. Neither Bhatt et al [12][13][14] nor Deshpande et al 15) had taken into consideration the stoichiometries of Sc(III) and Y(III) complexes and the existence of different species on their equilibria; they only determined the relative molar concentrations of complexes formed from the aqua M(III) ions with these two ligands by means of formation curves, leading to rather approximate values.…”

“…Neither Bhatt et al [12][13][14] nor Deshpande et al 15) had taken into consideration the stoichiometries of Sc(III) and Y(III) complexes and the existence of different species on their equilibria; they only determined the relative molar concentrations of complexes formed from the aqua M(III) ions with these two ligands by means of formation curves, leading to rather approximate values. Thus our third aim is introduce the reliable formation constants of complexes formed between Sc(III), Cr(III), Y(III) and these two ligands into the physical and analytical studies of these metal ions.…”

“…1. There have been some reports on the Sc(III) and Y(III) complexes of hydroxy naphthoic acids [12][13][14][15] ; but almost nothing is known about the complexes between Cr(III) and these two naphthoic acids. However, the stabilities and stoichiometries of the complexes formed with Cr(III), Sc(III), Y(III) and hydroxy benzoic acids were already determined by us.…”

“…Some reports on binary complex formation abilities are available in the literature for various metal ions. [12][13][14][15][16][17][18][19][20][21] Currently our main aim is to investigate the binding abilities of 1,2-HNA and 3,2-HNA to Cr(III), Sc(III) and Y(III) and to determine the formation constants of their complexes.…”