A. T. Teleshev

Sonochemical activation of condensing phosphorylation of bifunctional hydroxyl-containing compounds

Condensing phosphorylation of 1,6-hexanediol, 1,4-dihydroxybenzene, 4,4′-dihydroxybiphenyl, and 2,2-bis(4′-hydroxyphenyl)propane by phenylphosphonous acid tetraethylamide was effected by treatment of the disperse reaction system with high-frequency sound. This treatment ensures efficient shift of the phase equilibrium in the course of condensation and increases the yield of phenylphosphonous acid oligoesters.

Features of condensation of 4,4′-Dihydroxybiphenyl with phenylphosphonous tetraethyldiamide

Abstract4,4′-Dihydroxybiphenyl was condensed with phenylphosphonous tetraethyldiamide. The moleccular mass, chemical composition, and structural features of the product, oligo(4,4′-biphenylene phenylphosphonite), were elucidated using the method of matrix-activated laser desorption/ionization, with a time-of-flight (TOF) mass analyzer. The oligophenylphosphites containing labile P-N bond, which are unstable under conditions of recording mass spectra, were stabilized by conversion into oligophenylphosphonates. 1H-Tetrazole catalyzes the reaction of phenylphosphonous tetraethyldiamide with 4,4′-dihydroxybiphenyl. Cross-linking in the solid state of the oligo(4,4′-biphenylene phenylphosphonite) containing terminal phosphonamidite group leads to gradual increase in the molecular weight and is accompanied by redox processes.

Oxidation of phenylphosphonites with aqueous hydrogen peroxide

An effective route to the oxidation of organic derivatives of trivalent phosphorus with an aqueous solution of hydrogen peroxide was considered. Phenylphosphonites, including those having a hydrolytically unstable phosphorus-nitrogen bond were involved into the oxidation. The identification of oxidation products, the phenylphosphonates, was carried out using the method of ion cyclotron resonance mass spectrometry with Fourier transform combined with electrospray ionization, and by 31P and 1H NMR spectroscopy. The influence of an effective antioxidant of natural origin, quercetin, on the oxidation was demonstrated.

Electron spin resonance study of the cavitated larch wood

It was shown previously that the larch wood waste can be efficiently processed by passing as aqueous pulp through a disintegrator of cavitator type [1, 2]. By this procedure the wood waste is transformed into a new polymer material called “Cavitated wood.” Besides the cavitated wood, therewith are formed lowmolecular substances: the dihydroquercetin flavonoid, terpenes, terpenoids, etc. [2]. Apparently, the essence of the phenomenon lies in the reorganization of the polymer structure of the original wood raw material, by moving some of its –Ar–C–C–C–X nano-sized blocks. Let us call this lignin nano-isomerization.

NMR investigations of di-rhodium-tetraacetate complexes with cyclic phosphites

The formation of adducts in the system containing Rh2(OAC)4, cyclic amidophosphite [El2NPO(CH2)3O] and bicyclic phosphite [P(OCH2)3CEt] have been studied using low temperature 31P NMR. Varying the concentration of Rh2(OAc)4 made the signals due to a mono-adduct, a homoligated bis-adduct and a mixed bis-adduct observable in the 31P spectra. Iterational optimisation of the parameters of the spectra of symmetric bis-adducts showed a very strong correlation between the values of the coupling constants 1JRhRh and3JPP. The spectrum of the asymmetric adduct (amidophosphite-Rh-Rh-phosphite) yielded a well defined estimate of 3JPP. This value (793 Hz) is found to be between the values of the coupling constants for phosphite-phosphite and phosphite-phosphine interactions found by Boyar and Robinson. The integrals of the lines in the 31P spectra of the samples derived from different starting concentrations of Rh2(OAc)4 yielded values for the stability constants of the detected adducts. The mono-adduct of amidophosphite was found to be significantly more stable than that of phosphite.

A New Approach to the Design of Antioxidants Derived from 3,5,7,3',4'Pentahydroxyflavone

Quercetin pentaacetate (Qu(OAc)5) was obtained by the acylation of quercetin by method (5) and then reduced with sodium metal in ethanol. The features of the electronic structure of the quercetin pentaacetate reduction product were studied by analyzing the ESR spectra of ketyl resulting from the dissociation of the corresponding pinacolate. Figure 1 shows the ESR spectrum of the sodium ketyl of acetylated quercetin. The calculation of the spin density distribution using the Priroda software allowed us to assign a doublet with а Н = 2 G in the spectrum of quercetin ketyl to the

Novel composite materials based on cavitated wood

A topical trend in the industrial and ecological development of Russia is elaboration of the methods for integrated use of all components of natural raw materials, in particular, woodbased biomass. Note that the integrated processing of the woodbased bio� mass is possible only in close cooperation of various woodbased industries. These include production of traditional materials, energy sources, chemical prod� ucts, and biologically active compounds approaching the geochemically and energetically closed cycle tech� nology. Currently, all woodbased industries related to either mechanical or chemical processing of wood produce specific wastes although in different amounts. The difficulty of targeted standardized processing of these wastes is related to the necessity of strict indus� trial classification of the wastes and their averaging taking into account the physicochemical properties of the substances that form the material and parts of the trees. It is important that bulky wastes of woodbased biomass are formed upon extraction from wood of bio� logically active compounds such as terpenes, polypre� nols, and flavonoids, which are usually present in small amounts in the initial raw material (1). For example, the larch wood remainders after the removal of arabinogalactan and dihydroquercetin are large� scale wastes, their weight being about 85% of the wood weight (2, 3). A promising method for waste wood recycling is the production of plate materials without or with mini� mized use of synthetic binders. This trend is promising as regards the environmental safety of constructional materials. It was proposed to manufacture plate mate� rials from the compression molding material resulting from the extensive physicomechanical modification of wood by explosive autohydrolysis occurring at elevated

Synthesis of metal complexes of polyalkylene(arylene) phosphorous amides

Reactions of phosphorous triamides with symmetrical diols in equimolar ratio were studied. These reactions result in formation of unique poly(oligo)amidophosphorous systems. The products obtained are used as ligands for the synthesis of metal complexes of a new type.