Supramolecular Complexes of Diglycidyl Methylphosphonate with Calix[4]resorcinolarene

Various-composition supramolecular complexes of calix[4]resorcinolarene with diglycidyl methylphosphonate were synthesized in organic solvents. The products have well-defined melting points, they are cleaved by acetylation, but remain unchanged on treatment with triethylamine.     

Investigation of metal-containing carbon nanostructures prepared from functional polymers

Metal-containing carbon nanostructures are prepared by heating poly(vinyl alcohol) in mineral media with a lamellar structure at a temperature below 300°C. It is demonstrated that three possible types of nanostructures can be formed, namely, multilayer carbon nanotubes, spherical carbon nanoparticles, and finely crystalline carbon structures. According to the data of transmission electron microscopy, the nanotube size falls in the range from 50 to 300 nm and the nanotubes themselves have a stranded structure.     

Photochemical properties and structures ofN-amino andN-azomethine derivatives of 2,4,6-triphenylpyridinium perchlorates

The molecular structures of the initial compounds and the products of photocyclization involving amino and azomethine groups in perchlorates ofN-amino (1) andN-azomethine (2) derivatives of 2,4,6-triphenylpyridinium cations were studied. Cations1 and2 have an essentially non-coplanar arrangement of the -Ph rings, and the product of photocyclization of2, cation3, is characterized by a flattened structure. It was found that the orientation of the lone electron pair of the N atom with respect to one of the planes of the -Ph rings in molecule1 is more favorable for monocyclization involving the amino group. The structure of molecule2 allows two routes of the photoreaction,viz., O N proton transfer and monocyclization with an -Ph ring. However, the structural features of molecule2 are more favorable for photocyclization.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 296–301, February, 1995.     

Synthesis of β-(1-3)-D-glucan under high pressure

The polycondensation of 1,2-0-exo-cyanethylidene-4,6-di-0-acetyl-3-0-trityl--D-glucopyranose (I) was accomplished in the presence of triphenylmethylium perchlorate in CH₂Cl₂ under the pressure of 14 kbar. The reaction was performed in the frozen solution after the phasic transition of the system, and led to the product of polycondensation which, after the removal of the protecting groups, gave the exactly regio- and stereo-regular -(1–3)-D-glucan.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2129–2132, September, 1990.     

Influence of Pu(IV) complex formation with 1,2-diaminocyclohexanetetraacetic acid on the reduction rate of quadrivalent plutonium

The behaviour of the complex ion formed by quadrivalent plutonium with 1,2-diaminecyclohexanetetraacetic acid (DCTA) in reductive media is studied.     

Synthesis and electronic absorption spectra of substituted tetrabenzoporphins

Zinc complexes of tetrabenzoporphins with substituents in the benzene fragments of the molecule were synthesized by the template tetramerization of substituted 3-carboxymethylphthalimidines or phthalimides with malonic or phenylacetic acid in the presence of zinc acetate, as well as by substitution reactions in the tetrabenzoporphin molecule. The metal-free compounds were obtained from the corresponding zinc complexes by the action of a stream of hydrogen chloride in chloroform. The electronic absorption spectra of the synthesized compounds were investigated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 773–779, June, 1988.     

Interpenetrating polymer networks of poly(dimethyl siloxane–urethane) and poly(methyl methacrylate)

Simultaneous IPNs of poly(dimethyl siloxane-urethane) (PDMSU)/poly(methyl methacrylate) (PMMA) and related isomers have been prepared by using new oligomers of bis(β-hydroxyethoxymethyl)poly(dimethyl siloxane)s (PDMS diols) and new crosslinkers biuret triisocyanate (BTI) and tris(β-hydroxylethoxymethyl dimethylsiloxy) phenylsilane (Si-triol). Their phase morphology have been characterized by DSC and SEM. The SEM phase domain size is decreased by increasing crosslink density of the PDMSU network. A single phase IPN of PDMSU/PMMA can be made at an M_c = 1000 and 80 wt % of PDMSU. All of the pseudo- or semi-IPNs and blends of PDMSU and PMMA were phase separated with phase domain sizes ranging from 0.2 to several micrometers. The full IPNs of PDMSU/PMMA have better thermal resistance compared to the blends of linear PDMSU and linear PMMA. © 1993 John Wiley & Sons, Inc.     

Application of isotope dilution method for mass- and alpha-spectrometric determination of burn-up and uranium,plutonium and transplutonium element content in VVER-440 spent fuel

In this report the procedures and the methodology of our versions of alpha- and mass-spectrometric techniques for destructive analysis of VVER spent fuel are discussed. These techniques allow the determination of the content of americium and curium isotopes with relative error 3–5%, that of plutonium isotopes with error ≤1% and of uranium isotopes ?0.3–0.4%. They allow one to determine the fuel burn-up using¹⁴⁸Nd monitor with relative error not exceeding 2% at confidence level P=0.95. The investigation was directed at the increase of sensitivity of analysis to ensure that the amount of analysed material should be equivalent to ～1 mg of irradiated uranium at mean burn-up values. These techniques are based on the isotope dilution method.     

Synthesis of 1,4-dihydropyridines having an N-alkylpyridinium substituent at the 4-position and their affinity towards liposomal membranes

There has been synthesized a series of 1,4-dihydropyridines having an N-alkylpyridinium substituent at position 4 with a varying length of hydrocarbon chain. Their affinity to model (liposomal) membranes has been studied. It was found that this affinity increased with lengthening of the hydrocarbon chain on the Npyridinium substituent at the 4-position of the 1,4-dihydropyridine ring. However, lengthening of the hydrocarbon chain in the 3,5-ester groups of the 1, 4-dihydropyridine ring led to a decrease in the binding to the liposome when a 4-(N-hexadecylpyridinium) substituent was present.Latvian Institute of Organic Synthesis, Riga LV-1006. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1112–1117, August, 1995. Original article submitted June 6, 1995.