The solvent extraction of europium and barium with 1-aryl-3-methyl-4-aroyl-5-pyrazolones

Eleven 1-aryl-3-methyl-4-aroyl-5-pyrazolone derivatives were synthesized. Their acid dissociation constants were determined spectrophotometrically; there was a linear relationship between them and Hammett's σ values. Europium and barium ions were readily extracted into benzene and n-octyl alcohol, respectively, at very low pH.     

Liquid-liquid extraction separation of zinc and cadmium with 1-phenyl-3-methyl-4-acyl-5-pyrazolones and tri-n-octylphosphine oxide

The extraction of zinc and cadmium with a mixture of a 1-phenyl-3-methyl-4-acyl-5-pyrazolone and trioctylphosphine oxide (TOPO) in various solvents is described. The extraction constants for systems based on eight 4-acyl compounds (C₃C₁₈) are reported. The 1-phenyl-3-methyl-4-stearoyl-5-pyrazolone/benzene system is most effective for the mutual separation of zinc and cadmium at pH 4.5; 20 μg of zinc can be separated efficiently from 20 mg of cadmium.     

Reaction of 4-arylidene-3-methyl-1-phenyl-5-pyrazolones with amines

The reaction of primary and secondary amines with 4-arylidenepyrazolones gives the corresponding ammonium salts of 4,4-benzylidenebis-5-pyrazolone derivatives but not adducts on the exocyclic C=C bond as was previously believed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 905–908, July, 1988.     

Solvent extraction of alkaline earth metals,and lithium with 1-phenyl-3-methyl-4-acylpyrazol-5-ones and trioctylphosphine oxide

The synergic extraction of magnesium, calcium, strongium, barium and lithium into cyclohexane or benzene containing 1-phenyl-3-methyl-4-acyl-pyrazol-5-one (HA) and tri-n-octylphosphine oxide (TOPO) was investigated as a function of pH, HA and TOPO concentration. The extracted species when the 4-benzoyl compound was used, were MA₂(TOPO)₂ (M = Mg, Ca, Sr), BaA₂(TOPO)₃ and LiA(TOPO)₂. When the 4-trifluoro-acetyl derivatives was used, the extracted species were the same except for SrA₂(TOPO)₃. Extraction constants for the synergic extractions were calculated.     

Influence of the temperature on the extraction of some lanthanides with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5

The extraction of Pr, Gd and Yb with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 (HPMBP) diluted in CHCl₃, C₆H₆, and CCl₄ at 288 K, 298 K, 308 K, and 318 K has been investigated. A compound of the typeMe(PMBP)₃HPMBP is formed in the organic phase. The values of the thermodynamic constants as well as of the parameters H°, S° and G° have been determined.

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Der Temperatureinfluß auf die Extraktion einiger Lanthaniden mit 1-Phenyl-3-methyl-4-benzoyl-5-pyrazolon

Zusammenfassung Es wurde die Extraktion von Pr, Gd und Yb mit 1-Phenyl-3-methyl-4-benzoyl-5-pyrazolon (HPMBP) in CHCl₃, C₆H₆ oder CCl₄ als verdünnendes Lösungsmittel bei 288 K, 298 K, 308 K und 318 K untersucht. Es wird eine Verbindung des TypsMe(PMBP)₃HPMBP in der organischen Phase gebildet. Die thermodynamischen Konstanten und auch die Parameter H°, S° und G° wurden bestimmt.

     

Mass spectrometric studies of some 4-acyl substituted 1-phenyl-3-methyl-5-pyrazolones

The electron-impact-induced fragmentation of 1-phenyl-3-methyl-5-pyrazolone and six 4-acyl substituted derivatives, have been studied with the aid of deuterium labelling, high resolution mass measurements and the metastable defocusing technique. The mass spectra of the pure keto and the pure enol forms do not show any significant differences. The predominant decomposition of the 4-acyl substituted pyrazolones is the α-cleavage with respect to the carbonyl group leading to intense peaks at m/e 201 by loss of the alkyl group. In the case of benzoyl and ethoxycarbonyl derivatives the α-cleavage is associated with a specific hydrogen rearrangement causing the loss of a benzene and an ethyl alcohol molecule, respectively.     

Solvent extraction of lanthanum(III), europium(III) and lutetium(III) with fluorinated 1-phenyl-3-methyl-4-benzoyl-5-pyrazolones into chloroform

A series of chelating reagents, 1-phenyl-3-methyl-4-(2-fluorobenzoyl)-5-pyrazolone, 1-phenyl-3-methyl-4-(3-fluorobenzoyl)-5-pyrazolone and 1-phenyl-3-methyl-4-(4-fluorobenzoyl)-5-pyrazolone, has been synthesized. The extraction of Ln(III), (Ln = La, Eu and Lu) into chloroform with these reagents at 30 +/- 1 degrees has been studied. The composition of the complexes extracted has been determined by the slope method, and the extraction constants K(ex), were measured. The presence of the fluorine atom in the reagents does not make the K(ex), values much different from those obtained with the parent pyrazolone.     

Thermodynamic parameters for the extraction of some lanthanides with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 and trioctylamine

The synergistic extraction of Pr, Gd and Yb with a mixture of 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 and trioctylamine diluted in C₆H₆, CHCl₃ and CCl₄ at 288 K, 298 K, 308 K and 318 K has been investigated. The values of the equilibrium constants as well as of H°, S° and G° have been calculated. The thermodynamic parameters indicate that the adduct formed becomes stable on the account of the enthalpy change which exceeds the antistabilizing effect of the entropy factor. A comparison is made to the extraction of the same elements with thenoyltrifluoroacetone.

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Die thermodynamischen Parameter für die Extraktion einiger Lanthaniden mit 1-Phenyl-3-methyl-4-benzoyl-5-pyrazolon und Trioctylamin

Zusammenfassung Es wurde die synergistische Extraktion von Pr, Gd und Yb mit einer Mischung von 1-Phenyl-3-methyl-4-benzoyl-5-pyrazolon mit Trioctylamin in C₆H₆, CHCl₃ und CCl₄ bei 288 K, 298 K, 308 K und 318 K bestimmt. Die Gleichgewichtskonstanten und die Werte für H°, S° und G° wurden berechnet. Die thermodynamischen Parameter legen den Schluß nahe, daß die Stabilität des gebildeten Addukts in Änderungen der Enthalpie begründet ist, wobei der destabilisierende entropische Effekt übertroffen wird. Die Ergebnisse werden mit der Extraktion mittels Thenoyltrifluoraceton verglichen.

     

Negative ion mass spectra and structure of 4-substituted 1-phenyl-3-methyl-5-pyrazolones

This is the first study of the electron capture dissociative resonance (ECDR) mass spectra of 4-substituted 1-phenyl-3-methyl-5=pyrazolones. The major features of the fragmentation of these compounds under ECDR. conditions were found relative to their substituent properties. After loss of the methyl group from the nitrogen atom, the pyrazolone ring isomerizes to a pyrazole ring with localization of the negative charge on the oxygen atom of the carbonyl group. The intensity of the [M - Ch₃]^– fragment depends on the substituent properties.Communication 5 in the series on the Mass Spectroscopy of Biologically Active Compounds, For Communication 4, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1663–1670, December, 1985.     

Some observations on the extraction of zinc with 3-methyl-1-phenyl-4-trifluoroacetyl-pyrazolin-5-one

Extraction of zinc with 3-methyl-1-phenyl-4-trifluoroacetyl-pyrazolin-5-one /FAP/ into chloroform has been investigated as a function of pH. The extraction is masked with cyanide and citrate ions. The extracted zinc can be quantitatively stripped into appropriate aqueous solutions. The distribution data of other metal ions show that zinc can be separated from a number of elements. Few possible applications of such separations from analytical and radiochemical point of view have been suggested.     

Substoichiometric liquid-liquid extraction and determination of vanadium based on the synergic effect of thenolytrifluoroacetone and trioctylphosphine oxide

Vanadium(IV) is extracted synergically with thenoyltrifluoroacetone (HTTA) and trioctylphosphine oxide (TOPO) in cyclohexane as the mixed ligand complex, VO(TTA)₂TOPO. The synergic extraction constant is 10^5.06. The system can be used for the substoichiometric extraction of vanadium(IV); vanadium(IV) is extracted at pH 4.0–5.0 with a substoichiometric amount of HTTA in the presence of an excess of TOPO. The substoichiometric process combined with isotope dilution was successfully applied to the determination of vanadium(IV) in NBS-1633 coal fly ash; the value found was 222.5 ± 3.5 μg g^?1. The method is shown to be accurate and precise.     

Synthesis of 1-phenyl-3-methyl-4-alkyl-4-[N-methylbutyro(capro)lactyl]-5-pyrazolones

The corresponding hydrazones, which on heating are cyclized to give 1-phenyl-3-methyl-4-alkyl-(benzyl)-4-(2-oxopyrrolidinomethyl)- and 1-phenyl-3-methyl-4-alkyl(benzyl)-4-(N-methylcaprolactyl)pyrazolones, are formed in the reaction of alkyl(benzyl) (2-oxopyrrolidinomethyl)- and alkyl-(benzyl) (N-methylcaprolactyl)acetoacetic esters with phenylhydrazine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1546–1548, November, 1976.     

Solvent extraction of gold(III) with 1-phenyl-3-methyl-4-trifluoroacetylpyrazolone-5

A simple, rapid and selective separation procedure of gold based on its extraction with 1-phenyl-3-methyl-4-trifluoroacetylpyrazolone-5 has been developed. The dependence of the distribution ratio of gold on the pH of aqueous solutions, concentration of hydrochloric, nitric and perchloric acids and the organic solvents has been investigated. Decontamination factors for a number of metal ions with respect to gold are reported. Excellent separation of gold is obtained from many elements including noble metals. Citrate, cyanide, iodide, thiosulfate and thiourea completely mask gold, whereas oxalate does not interfere. Solutions of 1 M HCl, 0.2 M KCN, and the buffer of pH 0.8 readily strip gold from the organic phase. Some useful analytical applications of this procedure are discussed.     

Studies on extraction of copper(II) with 1-phenyl-3-methyl-4-acyl-5-pyrazolone

The extraction of Cu(II) with 1-phenyl-3-methyl-4-acyl-5-pyrazolone (HA), in different organic solvents has been studied. The extraction mechanism of Cu(II) and the composition of the extracted species has been determined. Cu(II) was extracted as CuA₂, or in the presence of TOPO, as CuA₂TOPO. The extraction constants do not change regularly with increasing the length of acyl chain in the 1-phenyl-3-methyl-4-acyl-5-pyrazolone derivatives. The effect of the temperature on the extraction of Cu(II) has also been investigated.     

Equilibria and kinetics of the extraction of gallium with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone

The equilibria and kinetics of the solvent extraction of gallium(III) from aqueous monochloroacetic acid [HA] media with a benzene solution of 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone [PMBP or HL] has been studied at 25 ± 0.1° and an ionic strength of 0.2. The species extracted was found to be GaL₃. The value of the acid dissociation constant of PMBP determined spectrophotometrically was 1.17 × 10⁻⁴. The values of the partition coefficient of PMBP and the extraction constant of its gallium complex between an aqueous and a benzene phase were found to be 3.72 × 10³ and 2.51 × 10⁴, respectively. The rate of extraction was first-order with respect to the concentrations of gallium(III) in the aqueous phase and PMBP in the organic phase, inversely first- and second-order with respect to the hydrogen-ion concentration and zero- and first-order with respect to the concentration of monochloroacetate ions. Two mechanisms operate for this extraction, depending on the pH of the aqueous phase, one where the formation of the first complex, GaL²⁺, between Ga³⁺ and L⁻ in the region of pH < 1.6 becomes the rate-determining step, and the other where the formation of the first complex between GaA²⁺ and L⁻ in the region of pH 2.0–2.3 is the rate-determining step. The rate constant for the first of these reactions was calculated to be 1.62 × 10⁴l.mole⁻¹.sec⁻¹, but that for the second could not be determined.     

Solvent extraction of lanthanide ions with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 (HPMBP)

The solvent extraction of Er(III), Yb(III) and Lu(III) by 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 (HPMBP or HL) in carbon tetrachloride has been studied as a function of thepH of the aqueous phase and the concentration of the extractant in the organic phase. The equation for the extraction reaction has been suggested as: $$Ln^{3 + } + 3HL_{(0)} \rightleftharpoons LnL_{3(0)} + 3H^ + \left( {Ln^{3 + } = Er,Yb, Lu} \right)$$ The extraction equilibrium constants (K _ex ) and two-phase stability constants (β ₃ ^x ) for theLnL ₃ complexes have been evaluated.     

Synthesis and prototropic tautomerism of 1-n-alkyl-3-methyl-4-nitroso-5-pyrazolones

Nitrosation at C-4 of 1-n-alkyl-3-methyl-5-pyrazolones is achieved in about 50% yield with sodium nitrite in hydrochloric acid medium. A tautomeric equilibrium in solution with a proton moving from the OH at C-5 to N-2 in the nitrosated pyrazolones is proposed.     

Solvent extraction of lanthanide ions with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 (HPMBP), II. Extraction of erbium(III), ytterbium(III) and lutetium(III) by HPMBP from aqueous-methanol solutions

The solvent extraction of lanthanides(III) (Ln=Er, Yb, Lu) by 1-phenyl-3-methyl-4-benzoylpyrazolone-5 (HL) in carbon tetrachloride from aqueous-methanol phase was investigated. The equilibrium constants for the extraction from aqueous –50% (v/v) methanol phase (K _ex ), two-phase stability constants of the complexesLnL ₃ ( ₃ ^* ) and stability constants of complexesLnL ²⁺,LnL ₂ ⁺ ,LnL ₃ ( _n ) (Ln=Yb, Lu) were calculated. It was confirmed that the addition of methanol to the aqueous phase causes a synergistic effect. The influence of methanol on the dissociation constant of HPMBP (K _a ) and the distribution constant of HPMBP (p _HL ) between carbon tetrachloride and water-methanol solutions was investigated.

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Extraktion von Seltenerdmetall-Ionen mit 1-Phenyl-3-methyl-4-benzoyl-pyrazolon-5 (HPMBP), II. Extraktion von Er(III), Yb(III) und Lu(III) aus Wasser-Methanol-Lösungen

Zusammenfassung Die Extraktion von Lanthaniden (Ln=Er, Yb, Lu) mittels 1-Phenyl-3-methyl-4-benzoyl-pyrazolon-5 (HL) in Kohlenstofftetrachlorid aus Wasser-Methanol Phase wurde untersucht. Die Werte der Gleichgewichtskonstante für Extraktion aus Wasser –50% (v/v) Methanol-Phase (K _ex ), der zweiphasigen Beständigkeitskonstante für die KomplexeLnL ₃ ( ₃ ^* ), sowie der Stabilitätskonstante des KomplexesLnL ²⁺,LnL ₂ ⁺ undLnL ₃ ( _n ) (Ln=Yb, Lu), wurden berechnet. Es wurde festgestellt, daß die Zugabe von Methanol zur wäßrigen Phase einen synergistischen Effekt hat. Der Einfluß von Methanol auf die Dissoziationskonstante von HPMBP (K _a ) und die Verteilungskonstante des HPMBP (p _HL zwischen organischer und wäßrig-methanolischer Phase wurde untersucht.

     

Recovery of neptunium from macroamounts of uranium by extraction with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5

Conditions for neptunium recovery from nitrate solution containing large amounts of uranium by extraction with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 (PMBP), and a mixture of PMBP with di-2-ethyl-hexylphosphoric acid (HDEHP) were studied. A two-stage technique, based on removal of uranium macroamounts at the first stage by means of extraction of uranium with PMBP and HDEHP mixture, and neptunium extraction by PMBP at the second stage, was suggested.     

Effect of inorganic aqueous anions on the synergic extraction of cadmium and zinc with 1-phenyl-3-methyl-4-benzoyl-pyrazol-5-one (HPMBP) and lipophilic ammonium salts

As a part of a systematic study of the synergic extractions of metals with mixtures of acidic chelating extractants and lipophilic anion-exchangers (B, X with X^?6 inorganic anion), the extractions of M  Cd and Zn from perchlorate, nitrate and sulphate media with 1-phenyl-3-methyl-4-benzoyl-pyrazol-5- one (HL) and tri-n-octylammonium salts (TOAH.X) or aliquat 336 (TOMA.X) in toluene have been investigated. Three key equilibria describe the extractions: (a) M²⁺+2$\text{HL}$?$\text{ML}{}_2$+2H⁺. (b) $\text{B.X}$ +$\text{HL}$?$\text{B.L}$+H⁺+X^? with B efficiency TOMA < TOAH and X efficiency ClO₄ < NO₃ < SO₄. (c) $\text{ML}{}_2$+$\text{B.L}$?$\text{B.ML}{}_3$ with B efficiency toma > TOAH and Ni ～ Co > Cd > ZN.As a consequence of the conflicting orders of efficiencies of TOMA and TOAH in equilibria b and c, TOAH.X is a better synergic extractant from perchlorate medium than TOMA.X whereas the inverse is observed from nitrate and sulphate media. Equilibrium c is independent of the inorganic anions. Constants of equilibria a, b and c are given. B.ML₃ species are not extracted in 1-octanol.