Ethylenediamine-N,N,N′,N′-tetrakis(methylenephosphonic) acid as complexing agent

Metal derivatives of ethylenediamine-N,N,N′,N′-tetrakis(methylenephosphonic) acid (EDTMP, H₈L) with some bivalent ions—Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Pb(II) have been isolated in various stoichiometric ratios from aqueous medium. Electronic spectra indicate them to be six-coordinated. EPR studies of Cu(II) complexes show that they are tetragonally elongated. Magnetic moments of M₄L derivatives are very low due to antiferromagnetic exchange interactions, but the moments go on increasing for M₃Na₂L and M₂Na₄L and are normal for MNa₆L derivatives, due to isolation of paramagnetic centres by diamagnetic sodium ions. IR spectra and thermal stability of the complexes have also been studied.     

Extraction of americium and europium from perchloric acid solutions with N,N′-dialkyl-and N,N,N′,N′-tetraalkylpyridine-2,6-dicarboxamides

Extraction of americium and europium from perchloric acid solutions with pyridine-2,6-dicarboxamides was studied. The solvate numbers and Am/Eu separation factors were determined.     

The thermodynamic characteristics of step dissociation of trimethylenediamino-N,N,N′,N′-tetraacetic acid

The heat effects of step dissociation of trimethylenediamino-N,N,N′,N′-tetraacetic acid were determined by direct calorimetry at 298.15 K and I = 0.1, 0.5, and 1.0 (KNO₃). The thermochemical and potentiometric measurement data obtained under equal experimental conditions were used jointly to determine the standard thermodynamic characteristics of the equilibria studied. The results obtained are compared with the corresponding data on related compounds.     

Thermodynamics of cobalt(II) complexation with trimethylenediamine-N,N,N′,N′-tetraethanoic acid

The stability constants of cobalt(II) trimethylenediaminetetraacetates at 298.15 K and I = 0.1, 0.5, and 1.0 (KNO₃) are determined by the potentiometric titration method. The heat effects of formation of the cobalt(II) complexonate at 298.15 K and I = 0.1, 0.5, and 0.1 (KNO₃) are measured by the direct calorimetric method. The standard thermodynamic characteristics of the reactions under study are calculated. The results obtained are compared with the corresponding data for related compounds.     

Solvent extraction of uranyl (II) ion with N,N,N,N-tetrabutylsucinylamide from nitric acid solution

N,N,N,N-tetrabutylsuccinylamide (TBSA) in a diluent composed of 50% trimethylbenzene (TMB) and 50% kerosene (OK) can extract uranyl (II) ion from nitric acid solution. The results of extraction study suggested the formation of the 121 uranyl (II) ion, nitrate ion and N,N,N,N-tetrabutylsuccinylamide complex as extracted specis. The values of thermodynamic functions have been calculated.     

Solvent extraction of thorium(IV) ion with N,N,N,N-tetrabutylsuccinylamide from nitric acid solutions

It was found that N,N,N,N-tetrabutylsuccinylamide (TBSA) in a diluent composed of 50% 1,2,3-trimethylbenzene (TMB) and 50% kerosene (OK) can extract thorium(IV) ion from a nitric acid solution. The results of the extraction study suggested the formation of a 141 thorium(IV) ion, nitrate ion and N,N,N,N-tetrabutylsuccinylamide complex as extracted species. The related thermodynamic functions were also calculated.     

Internal rotation barriers in esters of N,N-dimethyldithiocarbamic acid

Conclusions The method of a complete analysis of the shape of the lines was used to determine the activation parameters of hindered rotation around the N-C bond in the molecules of N,N-dimethyldithiocarbamic acid esters. The value of the barrier in these compounds is lower than in the thioamides, and depends on the electronic and steric nature of the substituent on the sulfur atom.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1388–1390, June, 1976.     

Kinetic determination of 1,3-propanediamine-N,N′-diacetic-N,N′-di-3-propionic acid and in a mixture with ethylenediaminetetra-acetic acid

A kinetic method is proposed for the determination of propanediamine-N,N′-diacetic-N,N′-di-3-propionic acid, based on its inhibitory effect on the acetonitrile-catalysed oxidation of Pyrocatechol Violet by hydrogen peroxide. The concentrations of 1,3-propanediamine-N,N′-diacetic-N,N′-di-3-propionic acid determined ranged from 5.0 × 10^?7 to 4.0 × 10^?6 M with a relative standard deviation of up to 3.3%. The same indicator reaction can be applied to the determination of 1,3-propanediamine-N,N′-diacetic-N,N′-di-3-propionic acid and ethylenediaminetetra-acetic acid in mixtures. Mixtures of these acids in molar ratios from 1 ∶ 4.5 to 10 ∶ 1 have been analysed. Concentrations of 1,3-propanediamine-N,N′-diacetic-N,N′-di-3-propionic acid from 2.0 × 10^?7 to 1.0 × 10^?6 M and ethylenediaminetetra-acetic acid from 1.0 × 10^?7 to 9.0 × 10^?7 M were determined with relative standard deviations of up to 4.3 and 5.7%, respectively. The effect of foreign ions on the accuracy of these determinations was also investigated.     

Protonation constants of 1-hydroxyethylidene-1,1-diphosphonic acid, diethylenetriamino-N,N,N',N',N'-penta-acetic trans-1,2-diaminocyclohexane-N,N,N',N'-tetra-acetic acid

The stepwise stability constants for the protonation of hydroxyethylidenediphosphonic acid (HEDP), diethylenetriaminopenta-acetic acid (DTPA) and diaminocyclohexanetetra-acetic acid (DCTA) have been determined potentiometrically with a hydrogen electrode at an ionic strength of 1 (KCl) and at 10-35 degrees . The data were treated by a least-squares method for estimation of DeltaH and DeltaS values.     

Reaction of triethylgermyllithium with carboxylic acid N,N-dialkylamides

Conclusions The reaction of Et₃GeLi with the N,N-dialkylamides of the benzoic, acetic, and trimethylacetic acids leads to the corresponding acyltriethylgermanes, RCOGeEt₃, and the products of their transformation by the Li derivatives that are present.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 949–951, April, 1982.     

N,N,N',N'-Tetrabutyladipicamide as a new extractant in toluene of nitric acid and uranium (VI)

N,N,N',N'-Tetrabutyladipicamide (TBAA) was used for the extraction of nitric acid and uranyl(II) ion from nitric acid media into toluene. The effects of nitric acid, uranyl(II) ion, and extractant concentration, temperature and back extraction on the distribution coefficient of uranyl(II) ion have been studied. The main adduct of TBAA and HNO₃ is TBAA·HNO₃ in 1.0 mol/l nitric acid solution. The 1:2:2 complex of uranyl(II) ion, nitrate ion and TBAA as extracted species is further confirmed by IR spectra of the extraction of uranyl(II) ion with TBAA. The values of the thermodynamic parameters have also been calculated.     

Metal chelates of phosphonate-containing ligands-III Analytical applications of N,N,N',N'-ethylenediaminetetra(methylenephosphonic) acid

N,N*,N',N'-Ethylenediaminetetra(methylenephosphonic) acid is used as a titrant for the direct determination of Cu, Co and Ni, with murexide as indicator. Indirect titrimetric procedures are suggested for the determination of silver, mercury, zinc and cyanide and both direct and indirect methods are applied for the analysis of binary mixtures of silver (or mercury) and copper (cobalt or nickel). The stoichiometry of the reaction, interferences of some metal ions and the pH effects on the complexation reactions are discussed. The values of the equilibrium constants of the protonated CuH(n)L (n = 1, 2, 3 and 4) as well as the unprotonated CuL chelates have been measured.     

The titrimetric determination of beryllium(II) with 1,2-phenylenediamine-N,N,N′,N′-tetraacetic acid

Beryllium (ca. 10^?2?10^?4 M) is determined by adding excess of 1,2-phenylenediamine-N,N,N′, N′-tetraacetic acid (PhDTA, H₄L) and back-titrating with copper(II); arsenazo-I serves as indicator. Formation constants of BeL and BeHL were determined by potentiometry: log K_BeL=6.48±0.02 and log K^H_BeHL=3.48±0.03 (25°C, I=1 M in NaClO₄). Expressions for the titration curve are given together with theoretical errors.     

New direction of the reaction between N,N′-disubstituted hydrazine and nitric acid

Conclusions The action of conc. HNO₃ on N,N-bis-(2,2-dinitropropyl)hydrazine and azo-(2,2-dinitro)propane at low temperatures was investigated, and it has been shown that in both cases 2,2-dinitropropionylhydrazone of 2,2-dinitropropionaldehyde is formed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1202–1203, May, 1970.     

Reactions of N,N-dimethoxyamine with acid chlorides and isocyanates

N,N-Dimethoxyamines are smoothly acylated by pnitrobenzoyl chloride and phosgene and carbamoylated by isocyanates. However, N-methoxy-N-benzyloxyamine is not alkylated by benzyl bromide and unsaturated activated compounds.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2384–2385, October, 1989.     

Synthesis of N,O-disubtituted 3-hydroxymethyl-7-Aminocephalosporanic acid

A method has been developed for the preparation of tert-butoxycarbonylandno-3-hydroxymethylceph-2-em-4-carboxylic acid, which is an intermediate for the preparation of new antibiotic derivatives with antibacterial, anti-inflammatory, or antitumor activity.