S. V. Matveev

β-Diphenylphosphorylated alkanones and related compounds: synthesis and structure

The reactions of diphenyl(diisopropyl)chlorophosphine with arylidene(heteroarylidene)-acetones and 3-benzylidenepentane-2,4-dione in the presence of acetic acid proceed at a high rate at room temperature to afford the corresponding β-diorganylphosphorylated alkanones and alkanediones in high yields. The reaction of diphenylchlorophosphine with 4-methoxybut-3-en-2-one and dibenzylideneacetone carried out under similar conditions at the equimolar reagent ratio can serve as a convenient method for the synthesis of unique β-diphenylphosphorylalkenones. The structures of compounds obtained were established by IR, Raman, and NMR spectroscopy and X-ray diffraction.

Complexes of (2-methyl-4-oxopent-2-yl)diphenylphosphine oxide with uranyl and neodymium nitrates: synthesis and structures in the solid state and in solution

The reactions of (2-methyl-4-oxopent-2-yl)diphenylphosphine oxide (L) with uranyl and neodymium nitrates afforded complexes with compositions M: L = 1: 2 and 1: 3. These complexes were characterized by X-ray diffraction, IR spectroscopy, and elemental analysis. In the solid complexes, phosphine oxide L has a variable denticity. Studies by 1H and 31P NMR and IR spectroscopy showed that in chloroform, the mononuclear complexes [UO2(O-L)2-(O,O-NO3)2], [Nd(O-L)2(O,O-NO3)3] and [Nd(O-L)3(O,O-NO3)3] are neutral, and the ligand molecules are coordinated to the metal cation through the phosphoryl oxygen atom.

Synthesis and coordination properties of new preorganized ligand on the triphenylphosphine oxide platform

Tris(2-cyanomethoxyphenyl)phosphine oxide was synthesized by the reaction of tris-(2-hydroxyphenyl)phosphine oxide with chloroacetonitrile. Its coordination properties were studied for the complexation with neodymium(iii) and copper(ii) nitrates using vibrational spectroscopy, NMR, and quantum chemical calculations.

Controlled modification of the quartz surface by amino groups

Abstract A simple and reproducible method for the determination of amino groups at the quartz surface is proposed. It is based on the reaction of amino groups with labelled H3-acetic anhydride. The method has been used to measure amino groups of immobilized γ-minopropyltriethoxysilane. The reaction of γ-aminopropyltri-ethoxysilane with quartz takes place in presence of a given content of γ-glycidoxypropyltriethoxysilane. This approach allows to obtain a quartz surface with predetermined amino groups density.

Crystal and molecular structure and vibrational spectra of 2,6-bis(diphenylphosphorylmethyl)-4-methylphenol and its complex with cerium(III) nitrate

The structure of 2,6-bis(diphenylphosphorylmethyl)-4-methylphenol 2,6-[Ph2P(O)CH2]2-4-MeC6H2OH(L1) and its 1: 1 complex with cerium(III) nitrate were studied by X-ray diffraction. A rather strong intramolecular hydrogen bond P=O…H-O (O…O, 2.646(1) Å) exists in the L1 molecules. In the crystal, the molecules are combined into centrosymmetric dimers through the stacking interaction between the central phenol rings; the distance between the ring planes is 3.39 Å. In the complex molecule, [Ce(L1)(NO3)3 · Me2C(O)], the neutral ligand L1 is tridentate and the three nitrate ions are bidentate, and the tenth coordination site is occupied by acetone oxygen. No intramolecular H-bonds are present. In the crystal, the complex molecules are combined into centrosymmetric dimers through intermolecular hydrogen bonds O-H…O-NO2 (O…O, 2.713(8) Å). The vibrational (IR, Raman) spectra of the ligand and the complex were studied and the principal bands were assigned. According to IR spectroscopy, the P=O…H-O intramolecular hydrogen bond is retained in both the ligand and the complex molecules.

2,4-Bis(diphenylphosphorylmethyl)mesitylene: Synthesis and complex formation with lanthanide nitrates. Crystal structure of [Nd(L1(NO3)3 · Me2CO]

A new bisphosphoryl ligand, 2,4-bis(diphenylphosphorylmethyl)mesitylene (L1), has been synthesized. Upon the interaction of L1 with lanthanide nitrates, stable mononuclear chelates [Ln(L1)n(NO3)3] (Ln = Ce(III), Nd(III), Er(III); n = 1, 2) were obtained. The structure of the complexes in solid state and in solution was studied by vibrational (IR and Raman) spectroscopy, X-ray diffraction, and conformational (molecular mechanics) analysis.

Extraction of REE(III), U(VI), and Th(IV) from HNO 3 and HClO 4 solutions with (α-pyridyl)tetraphenylmethylenediphosphine N,P,P '-trioxide

Extraction of microamounts of U(VI), Th(IV), and REE(III) from HNO3 and HClO4 solutions with solutions of (α-pyridyl)tetraphenylmethylenediphosphine N,P,P-trioxide in dichloroethane was studied. The stoichiometry of the extractable complexes was determined, and the influence of the extraction structure and aqueous phase composition on the efficiency and selectivity of the extraction of U(VI), Th(IV), and REE(III) into the organic phase was studied. Introduction of the pyridine N-oxide fragment into the methylene bridge of the tetraphenylmethylenediphosphine dioxide molecule to obtain (α-pyridyl)tetraphenylmethylenediphosphine N,P,P-trioxide leads to a decrease in its ability to extract U(VI), Th(IV), and REE(III) from nitric acid solutions, whereas the U/REE separation factors increase. The REE(III) extraction efficiency considerably increases in going from nitric acid to perchloric acid solutions.

Amino-substituted gem-diphosphonic acids: Dissociation mechanism, complex formation and the structure of species in aqueous solutions

Dissociation mechanism of acids R 2 N(CH 2 ) n CR(PO 3 H 2 ) 2 and the structure of their metal complexes depend on R and N. Intramolecular H-bonds stabilize the cyclic conformations of the species.