On Phosphorylation of Dihydric Phenols with Amines of Phosphoric and Phenylphosphonic Acids

Abstract

With the aim to create macrocyclic phosphorus-containing heterocycles (new phosphorus crown-ethers) and corresponding polyesters the interaction between dihydric phenols and complete anides of phosphoric and phenylphosphonic acids was studied. It was shown that, according to reaction conditions and reagents ratio, the resulting products can have a linear structure, with oligo- (A) or polymexic (B) molecules, and a macrocyclic structure (C) alike : phospho(III)arylene crown-ethers obtained for example by the consecutive assembling of planned macrocyclic systems or by the direct interaction.     

Arene Phosphorus-Containing Macrocyclic Crown Ethers: Last Studies

Abstract

The data on the synthesis, structures, and chemical properties of macrocyclic compounds containing endo-cyclic atoms of tri- and pentavalent phosphorus are summarized. Methods for the synthesis of the described macrocycles are reported. Peculiarities of structure, chemical properties, particularly formation of complexes, catalytic activity, and practical applications are analyzed. The bibliography includes 155 references.     

Synthesis of the first unsymmetrical macroheterocycle containing endocyclic phosphorus atoms from pyrocatechol and hydroquinone

The first unsymmetrical phosphorus(III)-containing macrocycle having hydroquinone and pyrocatechol fragments, N,N,N′,N′-tetraethyl-2,4,11,13-tetraoxa-3,12-diphosphatricyclo[12.2.2.0^5,10]octadeca-1(16),5,7,9,14,17 hexaene-3,12-diamine, was synthesized in a stepwise mode from hexaethylphosphorous triamide, hydroquinone, and pyrocatechol. The product was converted into the corresponding P,P′-dioxide and P,P′-disulfide     

Regularity of the solution and well-posedness of a mixed problem for an elliptic system with quadratic nonlinearity in gradients

A boundary value problem for an elliptic system of equations is studied that arises in the analysis of a new hydrodynamic model describing charge transport in a planar semiconductor MESFET (metal semiconductor field effect transistor). The problem has a number of features, specifically, the equations of the system involve squared components of the gradients of the unknown functions; the boundary conditions are of a mixed character, i.e., Dirichlet and Neumann conditions are set on different portions of the boundary; and the boundary of the domain is a nonsmooth curve, namely, a rectangle. Under a certain optimal condition, the C ^1,α-regularity of a weakened solution of the problem is justified and its existence is proved, while its uniqueness is shown under additional constraints. The results are used to justify the stabilization method as applied to finding approximate stationary solutions of the hydrodynamic model.     

Polarized fluorescence of jet-cooled molecular iodine

The degree of polarized fluorescence of molecular iodine ¹²⁷I₂ cooled in a supersonic jet under rotationally selective excitation in the electronic transition B ³Π_0u ⁺-X ¹Σ _g ⁺ has been measured and calculated. It was found that the interaction of the angular momentum of the molecule with the nuclear spins of iodine atoms leads to a considerable depolarizing effect. This effect is most pronounced for small rotational quantum numbers of the angular momentum that are comparable with the total nuclear spin of the iodine molecule, which is equal to 5.