Potentiometric and Spectroscopic Studies on Yttrium(III) Complexes of Dihydroxybenzoic Acids

Aydın, Rahmiye; Özer, Ulviye

doi:10.1248/cpb.52.33

Cited by 15 publications

(20 citation statements)

References 14 publications

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“…Studies (Sahoo et al, 2008;Aydin and Özer, 2004) also indicated that carboxylate ion in 2,3-DHBA was not coordinated strongly with the metal ion rather it promoted the coordination or provided an anchoring effect for coordination of hydroxyl group at second position whose protonation constant was not known. As pH increases two more protons were released from catecholic part. )…”

Section: Structures Of Complexesmentioning

confidence: 99%

“…Equilibrium reactions of 2,3-dihydroxybenzoic acid (2,3-DHBA) with Sc(III), La(III) and Y(III) ions in aqueous medium have been investigated by potentiometric and and spectrophotometric methods (Sahoo et al, 2008;Aydin and Özer, 2004;Türkel and Özer, 2005). The aqueous chemistry of 2,3-DHBA complexes with metal ions, such as iron(III), copper(II), nickel(II) and manganese(II) have also been studied (Gerard et al, 1987;Jeżowska-Bojczuk et al 1990;Casale et al, 1992).…”

Section: Introductionmentioning

confidence: 99%

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Chemical speciation of 2,3-dihydroxybenzoic acid complexes with some biologically essential metal ions in 1, 2-propanediol–water mixtures

Hirpaye

Rao

2013

Chemical Speciation & Bioavailability

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Chemical speciation of Co(II), Ni(II), Cu(II) and Zn(II) complexes of 2,3-dihydroxybenzoic acid in 0.0-60.0% v/v 1, 2-propanediol-water mixtures maintaining an ionic strength of 0.16 mol dm -3 at 303±0.1 K has been studied pH metrically. The predominant complexes formed are ML, ML 2 and ML 2 H 2 for Co(II), Ni(II) and Zn(II) and ML, ML 2 , ML 2 H and ML 2 H 2 for Cu(II). Models containing different numbers of species were refined by using the computer program MINIQUAD75. Selection of the best fit chemical models was based on statistical parameters and residual analysis. The trend in variation of complex stability constants with dielectric constant of the medium is explained on the basis of electrostatic and non-electrostatic forces. Distributions of species, formation equilibria and effect of influential parameters on the stability constants have been presented. The possible structures of the various species are elucidated on the basis of the analysis of the pH-metric data.

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Section: Structures Of Complexesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Chemical speciation of 2,3-dihydroxybenzoic acid complexes with some biologically essential metal ions in 1, 2-propanediol–water mixtures

Hirpaye

Rao

2013

Chemical Speciation & Bioavailability

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“…15) This type of coordination of hydroxy carboxylic acids is not unusual for Cr(III), 37) Y(III) 7,14) and rare earths, 38) in addition to these hydroxy naphthoic acids. For the 1 : 2 mole ratio of Cr(III) to H 2 L ligand the occurrence of Cr(HL)L complex was assumed since Cr(III) can accomplish the coordination to HL Ϫ type monoprotonated and L 2Ϫ type deprotonated anion, as a result of d 3 electronic structure and the potentiometric titration results are in accordance with Cr(HL)L type stoichiometry.…”

Section: Resultsmentioning

confidence: 93%

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

Aksoy

Aydın

Türkel

et al. 2005

CHEMICAL & PHARMACEUTICAL BULLETIN

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We continue our studies on the complex equilibria between Cr(III), Sc(III), Y(III) and 1-hydroxy-2-naphthoic acid (1,2-HNA: H 2 L) and 3-hydroxy-2-naphthoic acid (3,2-HNA: H 2 L). We have reported the stabilities of the complexes between these metal ions and the title ligands. [1][2][3][4][5][6][7][8][9][10][11] The structural formulas of the studied ligands are shown in Fig. 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. [4][5][6][7][8][9][10][11] It is well known that the derivatives of naphthoic acids are used as dyes and reagents for spectrophotometric measurements since they form chelates with several metal ions, whereas hydroxy carboxylic acids of the naphthalene series are far less common as ligands for complexometric studies than hydroxy benzoic acids. 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.On the other hand, the humic substances are derivatives of hydroxy naphthoic and hydroxy benzoic acids and they are found in natural ligands. They can remove environmentally mobile ions like Cu(II), Fe(III) and Al(III) that originate from various industries since humic substances are easily coordinated from oxygen donor sites to these metal ions and form very stable chelates. [22][23][24][25][26][27] Cr(III), with Cr(VI), is one of the main pollutant during waste water treatment in our city, Bursa. 28) So, the removal of Cr(III) from waste water may be possible using 1,2-HNA and 3,2-HNA ligands. Therefore, our second aim is to determine the concentration of uncomplexed Cr(III) by means of the formation constants of its 1,2-HNA and 3,2-HNA complexes as a part of our research project.However, Bhatt et al. 12,13) were interested in the complex formation reactions of Sc(III) with 1,2-HNA and 3,2-HNA but they were mainly ternary complex forming systems. 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) complexe...

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“…Studies of DHBA complexation with various metal ions in solution can be found in the literature; e.g. beryllium [3] aluminium [1], yttrium [4], and copper [5]. Recently, the presence of 3,4-DHBA was also shown to affect the adsorption of the radionuc- For instance, the constants listed for 2,3-DHBA on the first row and for 3,4-DHBA on the last row of Table 1 can be found in many handbooks, both in print and online, but the origin of those values is somewhat unclear.…”

Section: Introductionmentioning

confidence: 99%

Potentiometric Study of Dissociation Constants of Dihydroxybenzoic Acids at Reduced Ionic Strengths and Temperatures

Rosenqvist¹,

Jonsson²

2017

AJAC

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The dissociation behavior of two dihydroxybenzoic acid isomers, 2,3-DHBA and 3,4-DHBA, at 281 K and 293 K was determined by potentiometric titrations in 0.01 M NaCl and 0.03 M NaCl. Results showed that the dissociation enthalpy for the carboxylic group in DHBA is close to zero, resulting in dissociation constants that do not vary appreciably with temperature, whereas the dissociation constants for the first hydroxyl group vary significantly with temperature. Increasing ionic strength was found to result in increased values for the second dissociation constant, whereas the effect on the first dissociation constant was less clear.

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Potentiometric and Spectroscopic Studies on Yttrium(III) Complexes of Dihydroxybenzoic Acids

Cited by 15 publications

References 14 publications

Chemical speciation of 2,3-dihydroxybenzoic acid complexes with some biologically essential metal ions in 1, 2-propanediol–water mixtures

Chemical speciation of 2,3-dihydroxybenzoic acid complexes with some biologically essential metal ions in 1, 2-propanediol–water mixtures

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

Potentiometric Study of Dissociation Constants of Dihydroxybenzoic Acids at Reduced Ionic Strengths and Temperatures

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