N. V. Davletshina

Synthesis and acid-base properties of aminophosphine oxides on the basis of natural amino acids

In recent years aminophosphonate derivatives of the natural amino acids attracted a considerable interest because of their pronounced physiological activity and specific complexing properties [1, 2]. However, the phosphine oxide derivatives of amino acids, which can show high efficiency in liquid and membrane extraction processes [3], were not described up to day. Using the Kabachnik–Fields reaction [1] in a dioctylphosphine–formaldehyde–amino acid threecomponent system, we synthesized a series of αaminomethylphosphine oxides containing structural fragments of glycine (I), β-alanine (II), and its N-butyl derivative (III) of the general formula Oct2P(O)· CH2NR(CH2)nC(O)OH, R = Oct2P(O)CH2, n = 1 (I); R = Oct2P(O)CH2, n = 2 (II); R = C4H9, n = 2 (III).

Synthesis, transport and ionophore properties of α,ω-biphosphorylated azapodands: V. Acid-base properties of new phosphorylated azapodands and α,ω-diamines and their participation in the membrane transport of I–III groups metal ions

Acid-base properties of newly and previously synthesized phosphorylated azapodands and α,ω-diamines and their amine precursors were studied. We found that they differ in the same range as has been found previously for the other aminophosphoryl compounds. The investigation of the processes of passive membrane ion transport of a series of metals of I–III groups by these reactants showed with all diphosphoryl diamines higher values of the transfer flow of the ions Sc(III), Nd(III), and Sm(III), than the ions of alkali and alkaline earth metals. Under the conditions of active membrane transport the azapodand IV exhibits high efficiency in the ion transport of Sr(II) and Ba(II), while diphosphoryldiamine III exhibits effective transport of Nd(III) ions. The factors that determine the efficiency and selectivity of the membrane extraction of the I–III groups metal ions by these diphosphoryl diamines are discussed.

Sinergetic membrane extraction of lithium ions with new organophosphorus carriers

We have studied membrane transport properties towards alkali metal ions of sinergetic mixtures of organophosphorus carries, N,N-bis(dihexylphosphorylmethyl)octylamine and didecylthiophosphorus or didecyldithiophosphorus acids. The influence of main parameters of extraction (pH of the feed phase as well as concentration and ratio of the carriers in the membrane) on the membrane transport rate and selectivity with respect to lithium has been analyzed. Conditions of efficient and selective (to separate K+ and Na+) membrane extraction of Li+ have been established. Advantages of the studied systems in comparison with some previously known ones are demonstrated.

Membrane extraction of metal ions by aminophosphoryl reagents in the active transport conditions

The process of membrane extraction of rare earth ions, Nd(III), Sc(III), and Sm(III), and also the accompanying them in the natural raw material ions Al(III) and Mg(II), by N,N-bis(dihexylphosphorylmethyl)octylamine (BPA) was investigated under the conditions of active membrane transport, and its high efficiency and selectivity was demonstrated with respect to the two first rare earth metals. The influence of principal parameters of the three-phase extraction process, including the nitrate ion concentration, the releasing aqueous phase acidity, the extracting agent concentration in the membrane, and the nature of the membrane solvent, on the membrane permeability, characterizing the efficiency and selectivity of membrane transporters, was established. Comparison of the membrane permeability in the process of transmembrane transport of Nd(III) and Sc(III) with BPA and monophosphorylated amines showed a significant advantage of the biphosphorylated amine extractant.

Synthesis, transport, and ionophore properties of α,ω-biphosphorylated azapodands: VII. Membrane transport of mineral acids by phosphorylated α,ω-diamines and azapodands

Phosphorylated α,ω-diamines and azapodands were shown to be effective agents in the processes of liquid and membrane extraction of substrates of different nature, including the ions of alkali and alkaline earth, rare and trace metals, and monoand polyhydric carboxylic acids [1-3]. It is known that extraction of metals from mining of raw materials is performed usually by transferring them into the aqueous phase in the form of salts of strong mineral acids, mostly nitric, hydrochloric, perchloric, sulfuric, and other acids. Therefore, information on the processes of extraction of inorganic acids by biphosphoryldiamide carriers is necessary rather than important: the optimization of metal extraction is not possible without this knowledge.

Synthesis, transport, and ionophoric properties of α,ω-biphosphorylated azapodands: VI. New cesium-selective electrodes based on the phosphorylated azapodands

New cesium-selective electrodes containing as an electrode active substance biphosphorylated azapodands: 1,8-bis(dioctylphosphorylmethylamino)-3,6-dioxaoctane (I), 1,10-bis(dioctylphosphorylmethylamino)-4,7-dioxadecane (II), and 1-(dioctylphosphorylmethylamino)-10-[(dioctylphosphorylmethyl)benzylamino]-4,7-dioxadecane (III) were developed, and the composition of the membranes of these electrodes was optimized. The high selectivity of electrodes based on the ionophores I–III toward Cs(I) ion, which can be determined on the background of the majority of the other ions of alkali and alkaline earth metals, including the close to it by size Rb(I) ion, was established.

Synthesis of the azapodands with phosphoryl terminal groups

GRAPHICAL ABSTRACT ABSTRACT New lipophilic phosphorylated azapodands with different substituents at the nitrogen atom were synthesized via the Kabachnik–Fields reaction in the three-component system: di-p-tolylphosphinous acid–formaldehyde–1,8-diamino-3,6-dioxaoctane. The reaction was carried out in toluene or acetonitrile media, with p-toluenesulfonic acid acting as a catalyst.

Synthesis of new lipophilic phosphine oxide derivatives of natural amino acids and their membrane transport properties toward carboxylic acids

One-pot procedures were developed for the synthesis of lipophilic N-(dialkylphosphorylmethyl) derivatives of natural amino acids with high yields from dioctyl- or didecylphosphine oxide, formaldehyde, and amino acid in the presence of amino acid hydrochloride. The reactions with some amino acids were also effective under catalysis by crown ether. The structure of the isolated N-(dialkylphosphorylmethyl) and N,N-bis(dialkylphosphorylmethyl)amino acids was determined on the basis of 1H, 13C, and 31P NMR and mass spectra; the structure of (S)-N-[(dicyclohexylphosphoryl)methyl]-α-alanine was proved by X-ray analysis, and intermolecular association of its molecules in crystal was characterized. Membrane transport properties of the new phosphorylated amino acids with respect to polyfunctional carboxylic acids were studied, and factors responsible for the efficiency and selectivity of membrane transport of acid substrates were estimated. Selective extraction of glutaric acid through a liquid membrane containing N,N-bis[(dioctylphosphoryl)methyl]-β-alanine was revealed.

Synthesis of new N -phosphorylmethyl amino acid derivatives. Steric structure of 2-[( S )- N -dicyclohexylphosphorylmethylamino] propanoic acid

Membrane extraction study of a number of natural hydroxy and amino acids with dipentyl 1-(benzylamino)cyclopentylphosphonate showed a quite high rate of transfer of these acid substrates, which was rationalized by complementary carrier–substrate interaction with formation of a stable complex [1]. Lipophilic α-amino phosphine oxides turned out to be equally efficient as carriers of simple organic acids; however, in the case of polyfunctional substrates, the transmembrane mass transfer with both types of extractants was insignificant because of shortage of coordination centers [2]. Obviously, receptor properties of α-amino phosphine oxides could be enhanced via introduction of a carboxy group which strongly tends to form hydrogen bonds. It seemed quite convenient to synthesize such compounds from structurally diverse natural amino acids. However, their use led to poor yields in Kabachnik–Fields reactions and in addition reactions of P–H compounds to imines (Pudovik reaction), which underlie general methods for the synthesis of α-amino phosphine oxides [3, 4]. We previously reported successful syntheses of N,N-bis(phosphorylmethyl) derivatives of glycine and β-alanine [5], as well as of N-(phosphorylmethyl)-(S)alanine derivative [6], from the corresponding amino acids via Kabachnik–Fields reaction. In this communication we describe a three-component version of this reaction with equimolar amounts of β-alanine or (S)-alanine hydrochloride, formaldehyde, and dihexylor dicyclohexylphosphine oxide. The reactions were carried out by heating the reactants for 3 h in boiling acetonitrile. According to ISSN 1070-4280, Russian Journal of Organic Chemistry, 2014, Vol. 50, No. 4, pp. 596–598.

Synthesis, transport, and ionophore properties of α,ω-biphosphorylated azapodands: VIII. Solvent extraction of the metal ions with N,N′-bis(dioctylphosphorylmethyl)-1,8-diamino-3,6-dioxaoctane

Liquid extraction from the aqueous solutions of perchloric acid with neutral azapodand extractant N,N′-bis(dioctylphosphorylmethyl)-1,8-diamino-3,6-dioxaoctane has been highly efficient in the cases of uranyl ions and some metals of groups II and III. To estimate the synergic effect of organophosphorus extractants, the neutral extractant was applied in the mixture with an acidic component, bis(pentadecyl)phosphoric acid. The synergic effect has exclusively been observed in the extraction of zinc and cadmium ions.