Showing papers in "Russian Chemical Bulletin in 1982"
16 citations
14 citations
TL;DR: A theory of diffusiophoresis has been developed and checked against the results of laboratory experiments as mentioned in this paper, and it is possible to lay down metallopolymeric and other types of films on any surface.
Abstract: 1.
Both potential and concentration gradients can give rise to particle motion in electrolyte solutions, movement of the latter type being designated as diffusiophoresis.
2.
A theory of diffusiophoresis has been developed and checked against the results of laboratory experiments.
3.
Studies on diffusiophoresis have been limited, despite the significance of the effect itself.
4.
Unless account is taken of this effect it is impossible to understand the technological processes involved in the formation of latex film by ion deposition on a base substrate.
5.
By using diffusiophoretic methods it is possible to lay down metallopolymeric and other types of films on any surface. These procedures can even be applied in cases in which the base is conducting, thus ruling out the use of electrophoretic methods.
13 citations
TL;DR: Aminomethylphosphines display dual reactivity with respect to alkylating reagents as discussed by the authors, where the attack of MeI is directed at the phosphorus atom, where as PhCH2Br, MeOSO2F, and HCl react at the nitrogen atom, producing phosphinomethylammonium salts.
Abstract: Conclusions1.In the reactions of aminomethylphosphines with the acylating reagents RCOCl, ClCN, and PhNCO the electrophilic attack is carried out at the phosphorus atom with cleavage of the C-P bond and the formation of acyl-, cyano-, and carbamoylphosphines.2.Aminomethylphosphines display dual reactivity with respect to alkylating reagents. The attack of MeI is directed at the phosphorus atom to form aminomethylphosphonium salts, where as PhCH2Br, MeOSO2F, and HCl react at the nitrogen atom, producing phosphinomethylammonium salts. The regiospecificity of the reaction depends on the basicity of the N atom, the size of the substituents on the P atom, and the type of alkylating reagent.
10 citations
9 citations
TL;DR: In this article, a polymolecular film is formed on an air-oxidized aluminum surface, where the oleate molecules are arranged so that the axes of their carboxyl groups stand at right angles to the metal surface.
Abstract: 1.
Adsorption of sodium oleate on an air-oxidized aluminum surface leads to the formation of a regularly oriented polymolecular film. In this film, the oleate molecules are so arranged that the axes of their carboxyl groups stand at right angles to the metal surface. The formation of this film lowers the work function of the metal by 0.03–0.05 V.
2.
Polymerization, with double-bond rupture in the sodium oleate molecule, results in firm bonding of oleate film to the metal surface.
3.
Thermal treatment of the polymerized adsorbed film leads to molecular reorientation.
4.
The adsorption of water vapor on the sodium oleate-modified aluminum surface is almost complete reversible, differing from adsorption on the original hydroxylated aluminum surface insofar as it leads to a reduction in the work function.
8 citations
TL;DR: Several laws governing acid-catalyzed nucleophilic substitution of hydroxyl groups in 2-alkyl(aryl)thioethanols have been revealed.
Abstract: 1.
The reactions of 2-alkyl(aryl)thioethanols with HCl in hydrochloric acid, alcohols, and thiols under anhydrous conditions have been studied. It has been shown that selective replacement of the hydroxyl groups in these compounds by chlorine atoms and alkoxy, alkyl, and arylthio groups occurs under certain conditions under catalysis by strong mineral acids.
2.
Several laws governing the acid-catalyzed nucleophilic substitution of hydroxyl groups in 2-alkyl(aryl)thioethanols have been revealed. In particular, an increase in the selectivity of the process with decreasing strength of the nucleophilic reagent has been established.
8 citations
TL;DR: In this article, a study of the 13C NMR spectra of hydroperoxides, peroxides and peroxy esters has been made, including diacyl peroxide.
Abstract: A study has been made of the13C NMR spectra of hydroperoxides, peroxides, peroxy esters, and diacyl peroxides.
7 citations
7 citations
TL;DR: A study was carried out on the feasibility of synthesizing isomeric 3-nitro-4-phenylfuroxane by means of trifluoroperacetic acid oxidation.
Abstract: 1.
A study was carried out on the feasibility of synthesizing isomeric 3-nitro-4-phenylfuroxane and 4-nitro-3-phenylfuroxane by means of the trifluoroperacetic acid oxidation of the corresponding isomeric 3-amino-4-phenylfuroxane and 4-amino-3-phenylfuroxane.
2.
3-Nitro-4-phenylfuroxane, which is the first reported 3-nitro derivative of furoxane, was synthesized.
7 citations
TL;DR: In this paper, a multistep process consisting of a series of consecutive and parallel steps, most of which (dehydrogenation, C5 and C6 dehydrocyclization, and hydrocracking) take place on the metal surface.
Abstract: 1.
The aromatization of ethylene and ethane in the presence of metal-alumina catalysts is a complex, multistep process consisting of a series of consecutive and parallel steps, most of which (dehydrogenation, C5 and C6 dehydrocyclization, and hydrocracking) take place on the metal surface.
2.
The aromatization of ethylene and ethane, as well as C5-C8 alkanes and cyclanes on zeolites, in contrast to metal-alumina catalysts, passes through a step involving formation of unsaturated low-molecular-weight fragments and their simultaneous oligomerization and aromatization on active sites containing bridging OH groups of the high-silicon zeolites.
TL;DR: In this article, a new method was proposed for obtaining α-chlorodinitro compounds by reacting chlorooximes with nitric anhydride, which was shown to be more efficient than the previous methods.
Abstract: A new method was proposed for obtaining α-chlorodinitro compounds by reacting chlorooximes with nitric anhydride.
TL;DR: The reaction of KBrO3 with thiophene in the presence of HBr in a two-phase water-ether system permits obtaining 2-bromothiophene, not contaminated with 2,5-dibromothio-morphomethane, in high yield as mentioned in this paper.
Abstract: The reaction of KBrO3 with thiophene in the presence of HBr in a two-phase water-ether system permits obtaining 2-bromothiophene, not contaminated with 2,5-dibromothiophene, in high yield.
TL;DR: In the reaction between 2-acyl-3-imidazoline 3-oxides and hydrazine, an intramolecular cyclization takes place with the formation of a new heterocyclic system, 2,3,6,8-tetraazabicyclo as discussed by the authors.
Abstract: 1.
Reaction of 2-acyl-1-hydroxy-3-imidazoline 3-oxides with monosubstituted hydrazines leads to monosubstituted hydrazones, derivatives of 2-acyl-1-hydroxy-3-imidazoline 3-oxide, which on oxidation give stable nitroxyl radicals of the imidazoline series.
2.
In the reaction between 2-acyl-3-imidazoline 3-oxides and hydrazine, an intramolecular cyclization takes place with the formation of a new heterocyclic system, 2,3,6,8-tetraazabicyclo[3.2.1]oct-3-ene.
3.
The oxidation of 6,8-dihydroxy-4,5,7,7-tetraalkyl-1-R-2,3,6,8-tetraazabicyclo[3.2.1]oct-3-enes leads to bicyclic nitroxyl radicals, 8-hydroxy-4,5,7,7-tetraalkyl-1-R-2,3,6,8-tetraazabicyclo[3.2.1]oct-3-en-6 oxyls, which on oxidation give 1,2,4-triazine 4-oxides.
TL;DR: In this paper, a study has been made of the kinetics and stoichiometry of the oxidation of the 2,2,6,6-tetramethylpiperidines and the corresponding 1-hydroxypiperidine by hydrogen peroxide in systems containing WO42−.
Abstract: 1.
Study has been made of the kinetics and stoichiometry of the oxidation of the 2,2,6,6-tetramethylpiperidines
and the corresponding 1-hydroxypiperidines
by hydrogen peroxide in systems containing WO42−. Both types of reaction lead to the quantitative formation of
piperidinoxyls and O2. The
and
oxidations are firstorder processes in the substrate and the catalyst, while their reaction rates are complex functions of the pH and the H2O2 concentration.
2.
A mechanism is proposed to cover the oxidation of
and
to
in H2O2 + WO42− systems.
TL;DR: In this paper, the standard enthalpy of formation for triaminoguanidinium perchlorate and nitrate has been calculated, and the enthalpies of formation of the triaminogluanide ion in dilute aqueous solution determined.
Abstract: 1.
Enthalpies of combustion and solution have been measured, and the standard enthalpy of formation calculated, for triaminoguanidinium nitrate.
2.
Standard enthalpies of formation have been calculated for triaminoguanidinium perchlorate and nitrate, and the enthalpy of formation of the triaminoguanidinium ion in dilute aqueous solution determined.
TL;DR: The reaction of 3-chlorocycloalkenes with excess aromatic amine leads to o-(2-cycloalkenyl)-substituted aromatic amines.
Abstract: The reaction of 3-chlorocycloalkenes with excess aromatic amine leads to o-(2-cycloalkenyl)-substituted aromatic amines.
TL;DR: The stereoselectivity of the glycosylation of 2-azido-2-desoxy-D-galactopyranosylhalides was studied and determinative group specific oligosaccharides were synthesized.
Abstract: 1.
The stereoselectivity of the glycosylation of 2-azido-2-desoxy-D-galactopyranosylhalides was studied.
2.
2-Azido-3,4,6-tri-O-benzyl-2-desoxy-β-D-galactopyranosyl chloride was proposed as a new glycosylating agent for the synthesis ofα-galactosaminides.
TL;DR: In this paper, the authors apply two models, the adsorbed-solution model and the dispersed-phase model, to the analysis of the dependence of the thermodynamic functions of an adorption system on the parameters of the equilibrium gas phase.
Abstract: 1.
The application of two adsorption models — the adsorbed-solution model and the dispersed-phase model — to the analysis of the dependence of the thermodynamic functions of an adsorption system on the parameters of the adsorption equilibrium permits the adsorption system to be regarded as a solution at small degrees of filling and as a dispersed phase at high degrees of filling.
2.
The presence of maxima on the curves of the temperature dependence of the isosteric heat capacity of the adsorbate at high degrees of filling apparently indicates the presence of associates of molecules in the adsorbate, as a consequence which the properties of the adsorption system gradually approach the properties of the equilibrium gas phase.
TL;DR: In this article, the stereochemistry of 2-(α-carbinol)norbornadiene complexes of rhodium and their mass spectra were established. But the relationship between the stereochemical properties and the spectra was not investigated.
Abstract: Correlations were established between the stereochemistry of 2-(α-carbinol)norbornadiene complexes of rhodium and their mass spectra.
TL;DR: The rate constants for the reactions of OH radicals with Np(IV) and NpV ions in aqueous perchloric acid solutions are practically independent of the acidity of the medium and are quite high, in order to exclude the recombination of the OH radicals in the presence of these ions as mentioned in this paper.
Abstract: The rate constants for the reactions of OH radicals with Np(IV) and Np(V) ions in aqueous perchloric acid solutions are practically independent of the acidity of the medium and are quite high, in order to exclude the recombination of the OH radicals in the presence of these ions.
TL;DR: In this paper, a scheme of total synthesis has been developed into a process flow plan and has been put into commercial use, which offers the possibility of synthesizing numerous steroid compounds with greatly different types of structure; the properties of these compounds, particularly their physiological action, will be the object of future research.
Abstract: Methods have been developed for preparing steroid hormones (including estrogens, anabolics, contraceptives, and provitamins of the D group), which are important in medicine and veterinary practice, and also insect ecdysis hormones, which are promising materials for use in combating insects that are harmful to crops. A scheme of total synthesis has been developed into a process flow plan and has been put into commercial use. The proposed paths of synthesis also offer the possibility of synthesizing numerous steroid compounds with greatly different types of structure; the properties of these compounds, particularly their physiological action, will be the object of future research.
TL;DR: In this article, the oxidation potentials of neptunium, plutonium, and americium in the valence states from (III) to (VII) have been determined experimentally in 0.1-15 M NaOH.
Abstract: 1.
The oxidation potentials of neptunium, plutonium, and americium in the valence states from (III) to (VII) have been determined experimentally in 0.1–15 M NaOH.
2.
Heptavalent plutonium and americium are thermodynamically able to oxidize water with the evolution of oxygen in 0.1–15 M NaOH, neptunium(VII) in 0.1–7 M NaOH.
3.
All valence states of plutonium resist disproportionation in alkaline solutions; in the case of neptunium and americium only one disproportionation reaction is possible; of the hexavalent state in to penta- and heptavalent states. The degree of completion of the reaction can be calculated accurately from the oxidation potentials determined.
TL;DR: In this article, the catalytic activity of Cu(II) complexes with anion-exchange resin AN-251 in the liquid-phase oxidation of cumene was studied by a spin-trap method and the process takes place by a radical-chain homogeneousheterogeneous mechanism and simultaneously by a molecular mechanism.
Abstract: 1.
We have studied the catalytic activity of Cu(II) complexes with anion-exchange resin AN-251 in the liquid-phase oxidation of cumene. We have demonstrated by the spin-trap method that the process takes place by a radical-chain homogeneous-heterogeneous mechanism and simultaneously by a molecular mechanism.
2.
We have examined the structure of the Cu(II) complexes with AN-251 by EPE and IR spectroscopy and shown that the catalyst undergoes deep-seated changes in the course of the catalytic oxidation of cumene; in particular, the methyl groups of the 2-methyl-5-vinylpyridine branches of the ion-exchange resin are oxidized to form fragments ofα-picolinic acid, and the coordination sphere of the copper(II) ions is changed.
TL;DR: In this article, carbonaceous adsorbents with various types of pore structures can be prepared by heating activated carbons in argon at temperatures ranging from 1000 to 2000°C.
Abstract: 1.
Carbonaceous adsorbents with various types of pore structures can be prepared by heating activated carbons in argon at temperatures ranging from 1000 to 2000°C.
2.
X-ray studies show that crystallization and compacting of the carbon occur in carbons which have been subjected to such thermal treatment.
3.
A study has been made of the adsorption of water vapor by the adsorbents prepared in this manner. Treatment at 1000–1600°C leads to only an insignificant alteration in the number of primary adsorption centers in the 0.31–0.19 mmole/g interval.
TL;DR: Aminoazobenzene derivatives are vigorously oxidized by O2 to the corresponding benzotriazoles when CuCl-pyridine is used as the catalytic system as mentioned in this paper.
Abstract: o-Aminoazobenzene derivatives are vigorously oxidized by O2 to the corresponding benzotriazoles when CuCl-pyridine is used as the catalytic system.