Phosphorus acid derivatives from 3,6-di-tert-butylpyrocatechol

Conclusions The reaction of 3,6-di-tert-butylpyrocatechol with the acid chlorides of various phosphorus acids was studied: reaction with PCl₃ gives the spirophosphorane, while reaction with diphenylchlorophosphine gives the diphenyl-1,2-phenylenedioxyphosphorane.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2385–2388, October, 1978.     

Use of Green's functions of the Laplace equation in the solution of problems of thermoelasticity of anisotropic bodies

The solution of a boundary-value problem concerning the thermoleasticity of homogeneous anisotropic bodies under several general conditions has been represented by a uniformly converging quadrature series. An example is given.S. M. Kirov Ural Polytechnic Institute, Sverdlovsk. Translated from Mekhanika Polimerov, No. 5, pp. 823–829, Semptember–October, 1973.     

On the triplet nature of paramagnetic centers in conducting polymers

Temperature dependences of the magnetic susceptibility of solutions and powders of polyaniline synthesized by oxidative polymerization using two methods were measured by ESR in the temperature range from 123 to 423 K. The dependences observed can be described by the integral of susceptibility of the polymer fragments in the triplet state over the singlet—triplet splitting from E ₁ to E ₂ with constant weight. The susceptibility of the fragments was accepted to obey the Bleaney—Bowers equation. The most part of the experimental dependences can be presented as the sum of the temperature-independent susceptibility and the susceptibility obeying the Curie law. The both susceptibilities are described in a single manner at E ₁ < 0. In some cases, the comparison of the calculated and experimental dependences makes it possible to determine the length of the fragments L. The conditions of polymer synthesis, heating, and water vapors affect the E ₁ and E ₂ values. A similar analysis can be applied to other conducting polymers. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 316–321, February, 2008.     

Anionic condensations of 3,5-di-<Emphasis Type="Italic">tert</Emphasis>-butyl-4(2)-hydroxybenzaldehydes in the presence of weak bases

Products of the reactions of 4- and 2-hydroxy-3,5-di-tert-butyl-benzaldehydes with malonic acid, diethyl malonate, and acetic anhydride in the presence of weak bases were isolated and identified. The reactions of 3,5-di-tert-butyl-4-hydroxybenzaldehyde with malonic acid and acetic anhydride in the presence of sodium acetate and piperidine gave 3,5-di-tert-butyl-4-hydroxycinnamic acid. The reaction of its 2-hydroxy isomer with acetic anhydride stopped at the stage of formation of the corresponding O-acetyl derivative, while in the reaction with malonic acid the corresponding substituted cinnamic acid and its lactone (coumarin derivative) were formed as intermediate products in a transformation sequence finally leading to 3-(3,5-di-tertbutyl-2-hydroxyphenyl)-3-piperidinopropionic acid and 6,8-di-tert-butyl-2-oxo-3,4-dihydro-2H-chromen-4-ylacetic acid. Analogous differences were typical of reactions of isomeric 4- and 2-hydroxy-3,5-di-tert-butylbenzaldehydes with diethyl malonate. The transformations of the 2-hydroxy isomer were accompanied by hydrolysis and formation of an adduct of intermediate coumarin derivative with diethyl malonate and piperidine.     

Synthesis and study of photochromic asymmetric bis-spiropyran

Asymmetric indoline-benzoxazine bis-spiropyran showing improved photochromic properties due to the electron-donating methoxy group has been prepared by multistage synthesis. The molecular structure of 8-methoxy-3-methyl-4-oxo-2H-1,3-benzoxazine-2-spiro-2′H,8′H-pyrano-[2,3-f]chromene-8′-spiro-2″-1″,3″,3″-trimethylindoline has been studied by X-ray diffraction. After exposure to UV light, the absorption spectra display several long-wavelength maxima, which can correspond to different merocyanine isomers of the bis-spiro compound.     

Indium strontium hydrogen phosphate SrIn<Subscript>2</Subscript>[PO<Subscript>3</Subscript>(OH)]<Subscript>4</Subscript>: Synthesis and crystal structure

Indium strontium hydrogen nitrate SrIn₂[PO₃(OH)]₄ was synthesized under mild hydrothermal conditions (T = 180 or 200°C) and characterized using IR spectroscopy, chemical analysis, and thermal analysis. A structure model obtained ab initio was refined by the Rietveld method: a= 9.6412(1) Å, b = 13.763(1) Å, c = 9.3579(1) Å, R _obs = 0.0183, R _p = 0.0493 (space group B22₁2, Z = 4). The acentricity of the structure was confirmed by SHG tests (I _2ω/I _2ω(SiO2) ≈ 2.0). In the SrIn₂[PO₃(OH)]₄ structure, indium atoms reside in distorted InO₆ octahedra and form, together with PO₃(OH) tetrahedra, a mixed 3D structure {In₂[PO₃(OH)]₄} _3∞ ^2? whose voids are occupied by Sr²⁺ cations (CN = 8). The block-dimer In₂(HPO₄)₁₀ is the most informative unit of the framework. Blocks are condensed into infinite columns running in the [101] direction. The compound is thermally stable up to 400°C.     

Synthesis and proliferative activity of a new derivative of the lupan pentacyclic triterpenoids, <Emphasis Type="Italic">viz.</Emphasis>, the sulfobetaine based on betulin with a 4-(dimethylammonio)butane-1-sulfonate moiety

A new zwitterionic derivative of the lupan pentacyclic triterpenoid series, viz., the sulfobetaine with a 4-(dimethylammonio)butane-1-sulfonate moiety, was synthesized by quaternization of betulin 28-(2-dimethylaminoacetate) with 1,4-butane sultone. The sulfobetaine was found to possess a dose-dependent proliferative effect toward human embrionic kidney cells HEK293 and human T-lymphocytes. Betulin chosen as a comparison compound demonstrated an effect against cells of both the tumor (HepG2, Jurkat) and the normal origin (human HEK293 and T-lymphocytes) which differ from that of the sulfobetaine, inhibiting their proliferation. The new sulfobetaine can prove to be a promising basis for the development of reparative and immunostimulating agents.     

Synthesis and study of the properties of K2Y1 ? x ? yEuxTby(MoO4)(PO4) and K2Y1 ? x ? yEuxTby(MoO4)(PO4)1?δ(VO4)δ solid solutions

Al synthesized samples are isostructural and crystallize in the orthorhombic symmetry system, space group Ibca. Particles of the final product of ∼200 nm in size have been obtained. The introduction of the vanadate anion into the matrix composition leads to the lowering of the symmetry of the Eu³⁺ environment and to the rise of the defect luminescence at 450–550 nm because of the unit cell distortion. The luminescence of defects in terbium-europium-containing samples is determined by the sample surface area, which decreases on annealing. The τ, W ₀ and γ parameters of the luminescence kinetics of the samples have been determined.     

Chlorination of 3,6-di-<Emphasis Type="Italic">tert</Emphasis>-butyl-1,2-benzoquinone in two-phase catalytic system

Chlorination of 3,6-di-tert-butyl-1,2-benzoquinone in a two-phase catalytic system (CH₂Cl₂, HCl- H₂O, H₂O₂, Bu₄NCl) led to halogen addition at the C=C bond, and subsequent dehydrochlorination of the adduct gave 3,6-di-tert-butyl-4-chloro-1,2-benzoquinone. Chlorination of the latter afforded 3,6-di-tert-butyl-4,5-dichloro-1,2-benzoquinone.     

Synthesis and study of the properties of the solid solutions K2Y1−x Tb(Tm) x (MoO4)(PO4) and K2Y1−x Tm x (MoO4)(PO4)0.95(VO4)0.05

The solid solutions K₂Y_1?x Tb(Tm) _x (MoO₄)(PO₄) and K₂Y_1?x Tm _x (MoO₄)(PO₄)_0.95(VO₄)_0.05 were synthesized, which are isostructural and crystallize in the orthorhombic crystal system (space group Ibca). The luminescence intensity of the terbium-containing samples increases with increase in the terbium content. The thulium-containing samples are characterized by intense luminescence in the blue spectral region and concentration quenching of luminescence. The introduction of the vanadate anion adversely affects the luminescence intensity.