The self-organization properties of <Emphasis Type="Italic">n</Emphasis>-dodecylammonium α-glutamate/<Emphasis Type="Italic">n</Emphasis>-C<Subscript>5</Subscript>H<Subscript>11</Subscript>OH/water system

A biocompatible surfactant-n-dodecylammonium α-glutamate (GDA) with biodegradable and biocompatible properties was synthesized, and the phase behavior and the structural properties of GDA/n-pentanol/water system was studied by small-angle X-ray diffraction, electron spin resonance, and freeze-fracture transmission electron microscopy (FF-TEM). In the ternary phase diagram of GDA/n-pentanol/water system, there exist three isotropic regions—O/W, bicontinuous, and W/O structures, and two anisotropic regions—hexagonal liquid crystal (HEX), and lamellar liquid crystal (LLC) regions. UV irradiation causes the decrease in the interlayer space, d, of lamellar liquid crystal and in the radius, r, of column aggregates of hexagonal liquid crystal, but it has little effect on the structure of O/W and W/O microemulsions.     

Synthesis from geraniol of (2<Emphasis Type="Italic">E</Emphasis>,6<Emphasis Type="Italic">E</Emphasis>,10<Emphasis Type="Italic">E</Emphasis>,14<Emphasis Type="Italic">E</Emphasis>)-16-hydroxygeranylgeraniol and some of its derivatives

Several α,ω-bifunctional derivatives of E,E,E-geranylgeraniol were prepared via convergent synthesis starting with geraniol (8), which was converted in three steps into the tetrahydropyranyl ether of 8-chlorogeraniol (9) and 8-hydroxygeranylphenylsulfone (10). Combination of synthons 9 and 10 with subsequent reductive removal of the phenylsulfonyl group produced the tetrahydropyranyl ether of ω-hydroxygeranylgeraniol (5), hydrolysis of which gave exclusively trans-ω-hydroxygeranylgeraniol (1). Derivatives 5–7 of geranylgeraniol were synthesized using standard methods. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 231–234, May–June, 2007.     

Crystal Structure of a New Modification of <Emphasis Type="Italic">cis</Emphasis>-Bis(pivalyltrifluoroacetonato)copper(II)

Powder and single-crystal X-ray diffraction study of cis-bis(pivalyltrifluoro-acetonato)copper(II) has been performed (Bruker AXS P4 automatic diffractometer, MoK _β radiation, t = −25°C). Crystal data for C₁₆H₂₀CuF₆O₄: a= 9.980(7) Å, b = 19.236(13) Å, c = 20. 771(14) Å, space group Pbca, V = 3987(5) ų, Z = 8, d _calc = 1.512 g/cm³. The square-planar environment of the Cu atom (Cu-O_av 1.904 Å, =O-Cu-O_av 92.4°) is completed to bipyramidal by the atoms of the neighboring molecules, Cu...F 2.78 Å and Cu...C_γ 3.30 Å. The complex forms centrosymmetric pseudo dimers with Cu...Cu distances of 4.59 Å.Original Russian Text Copyright © 2004 by S. A. Gromilov, I. A. Baidina, P. A. Stabnikov, and G. V. Romanenko__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 5, pp. 893–898, September–October, 2004.     

Physico-chemical characterization of anhydrous <Emphasis Type="Italic">D</Emphasis>-mannitol

In this work the solid-state characterization of anhydrous D-mannitol has been performed: α and β modifications can be distinguished only by XRPD and FTIR as they show melting temperature and enthalpy that are the same within the standard deviation. The understanding of the thermal behaviour of the δ form (obtained by re-crystallization in acetone) has required XRPD experiments performed at variable temperature. This form during heating undergoes a solid phase transition to α modification. By cooling a melted sample, under a wide range of experimental conditions, a very fast crystallization occurs. Independently of the starting crystal form (β or δ form), the re-crystallization of D-mannitol from melt always leads to α form.     

Chemical Composition of <Emphasis Type="Italic">Silene viridiflora</Emphasis>

Neutral substances, carbohydrates, and microelements from the aerial part of Silene viridiflora in addition to the protein content and its amino-acid composition were determined. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 365–366, July–August, 2005.     

Initial anticrossing between Stark manifold <Emphasis Type="Italic">n</Emphasis> and <Emphasis Type="Italic">n</Emphasis>+1 in Na

We present the theoretical results for the positions and widths of the initial anticrossing between Stark manifold n and n + 1 in sodium, obtained by using the method of diagonalization in which zero-field wave functions are chosen from a kind of atomic potential model. These results can provide the quantitative information for understanding the microwave ionization process, whose rate-limiting step is probably the n to n + 1 transition performed at the first crossing between the outermost states of these two manifolds.     

Supercritical <Emphasis Type="Italic">n</Emphasis>-butane isomerization

Supercritical n-butane isomerization over the solid acid catalysts sulfated zirconia, TiO₂-supported H₄[Si(W₃O₁₀)₄] · xH₂O (Keggin-type heteropoly acid), and H-mordenite is studied in a flow reactor. The critical parameters of n-butane are calculated for a wide range of reaction conditions. Changing from gaseous n-butane to supercritical n-butane markedly extends the lifetime of the catalysts. Under supercritical conditions, the activity and selectivity of the catalysts are invariable, provided that the density of the reaction mixture is in the vicinity of the critical density of n-butane. After the catalysts are deactivated in the gas medium, they can be partially or completely reactivated in the supercritical fluid.Translated from Kinetika i Kataliz, Vol. 45, No. 6, 2004, pp. 942–946.Original Russian Text Copyright © 2004 by Bogdan, Klimenko, Kustov, Kazanskii.     

<Emphasis Type="Italic">Ab initio</Emphasis> study of aniline and <Emphasis Type="Italic">n</Emphasis>-propylamine associates with nitrobenzene and <Emphasis Type="Italic">m</Emphasis>-cresol

An ab initio (6-31G**) study of binary associates of aniline and n-propylamine with nitrobenzene and m-cresol has been carried out. The structures corresponding to the total energy minimum of the system have been found for the associates, and their geometrical and energy characteristics have been determined. Basic types of intermolecular interactions have been established, and their effects on the reactivity of the amino group have been investigated.Original Russian Text Copyright © 2004 by I. A. Novakov, V. V. Korolkov, A. I. Pavlyuchko, B. S. Orlinson, and L. A. GribovTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 4, pp. 595–601, July–August, 2004.This revised version was published online in April 2005 with a corrected cover date.     

Fatty acids of <Emphasis Type="Italic">Stachys milanii</Emphasis> seeds

For the first time the total acid composition of the seeds of Stachys milanii Petrovic, a species endemic to the central and eastern Balkan Peninsula and growing spontaneously at two localities, was examined by GC and GC/MS. The major fatty acid was linoleic or oleic acid. Besides fatty acids that represent the usual seed oil constituents, 6-octadecynoic and 9-oxononanoic acid were identified in considerable amounts. The high content of 6-octadecynoic acid makes S. milanii seed oil a good potential source for the active substance in antifungal preparations. From the chemotaxonomical point of view, small amounts of octadecatrienoic acid detected in the seeds suggested classification of S. milanii as an archaic taxon. Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 315–317, July–August, 2007.     

Synthesis of magnesium catecholate and <Emphasis Type="Italic">o</Emphasis>-semiquinone complexes by oxidation of the metal with 3,6-di-<Emphasis Type="Italic">tert</Emphasis>-butyl-<Emphasis Type="Italic">o</Emphasis>-benzoquinone

Oxidation of amalgamated magnesium metal with 3,6-di-tert-butyl-o-benzoquinone (1) in different aprotic organic solvents afforded magnesium catecholate and bis-o-semiquinolate complexes. The catecholate derivatives of magnesium CatMgL₂ (Cat is the 3,6-di-tert-butyl-o-benzoquinone dianion, L = THF or Py) were synthesized in high yields in pyridine and tetrahydrofuran, respectively. The reactions in diethyl ether or dimethoxyethane produced hexacoordinated metal bis-o-semiquinolates SQ₂MgL_n (SQ is the 3,6-di-tert-butyl-o-benzoquinone radical anion, L = Et₂O, n = 2; L = DME, n = 1). The reaction with the use of toluene as the solvent gave a magnesium bis-o-semiquinolate complex containing the coordinated unreduced o-quinone molecule. The molecular structures of the [CatMgPy₂]₂ and SQ₂Mg·DME complexes were established by X-ray diffraction. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 92–98, January, 2007.     

Structure and photochromism of 2-(<Emphasis Type="Italic">N</Emphasis>-acyl-<Emphasis Type="Italic">N</Emphasis>-arylaminomethylene)benzo[<Emphasis Type="Italic">b</Emphasis>]thiophen-3(2<Emphasis Type="Italic">H</Emphasis>)-ones

It was shown by electron absorption spectroscopy and X-ray diffraction analysis that steric strains in photochromic 2-(N-acyl-N-arylaminomethylene) benzo[b]thiophen-3(2H)-one molecules ortho-substituted in the N-phenyl ring increase the quantum yield of the N→O photoinduced rearrangement in accord with an increase in the steric constant of the ortho-substituent.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2151–2155, October, 2004.     

Crystal and molecular structure of two polymorphic modifications of <Emphasis Type="Italic">bis</Emphasis>(2,3-pentamethylene-3,4-dihydroquinazolinium) tetrachlorozincate

An X-ray diffraction investigation of two polymorphic modifications of the zinc chloride complex of 2,3-pentamethylene-3,4-dihydroquinazoline hydrochloride, grown under different temperature conditions, has been carried out. The geometry of the molecular complex is analyzed.     

A new method for modification of <Emphasis Type="Italic">CN</Emphasis>-palladacycles

The reaction of benzylaminate CN-palladacycle with chlorine dioxide was found to produce the 3-chlorine-substituted analog through the formal insertion of chlorine into the Pd-C bond followed by repeated ortho-palladation of the modified ligand. The structure of the resulting dimeric complex was confirmed by X-ray diffraction study of its triphenylphosphine derivative. A comparison of the ¹H NMR spectra of the phosphine adducts of the starting and chlorinated complexes shows high conformational stability of the new palladacycle. Advantages of the new route to conformational stabilization of labile palladacycles are discussed. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2010–2019, September, 2005. Dedicated to Academician N. S. Zefirov on the occasion of his 70th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2010–2019, September, 2005.