SovietRxiv · Open Access in English
Rediscovering the Soviet scientific archive, in English
25357 full-text translations 14926 English PDFs 22539 abstracts
Showing 50 of 4600 papers in Chemistry
A general synthesis of 1,4-dinitrobutadienes-1,3 is described, based on oxidation of disodium salts of substituted 1,4-dinitrobutene-2 with bromine, iodine, ferricyanide, or silver nitrate in ether or aqueous media. Raman spectral intensity analysis is used to assess conjugation and assign cis-cis a…
This study examines whether transition-metal complexes known to activate hydrogen can also fix molecular nitrogen under mild homogeneous conditions, and how added hydrogen affects this process. Systems formed from transition-metal acetylacetonates or tetraethoxytitanium with organolithium, Grignard,…
This study examines the electrical conductivity of lithium alkyl solutions in nonpolar solvents as a probe of their role in stereoregular diene polymerization and of the effects of electron donor additives. Conductivity measurements were carried out for ethyllithium and n-butyllithium in benzene or …
The paper examines mutual solubility in the ternary system water, nitric acid, and butyl ester of dibutylphosphinic acid at 25°C, motivated by the use of this compound as an extractant for metal salts and acids. Solubility boundaries and conjugate phase compositions were determined by Alekseev’s met…
This paper examines anomalous variations in interatomic distances among metallic lanthanoids against the general trend of lanthanoid contraction. Using a previously derived formula relating distance to coordination number, atomic number, core and bonding electrons, and the contribution of 4f electro…
This paper examines whether acid-induced, nonenzymatic cyclization of acyclic isoprenoids can proceed stereospecifically in the formation of a decalin system. Using individual cis-6,7-trans-10,11 and trans-6,7-trans-10,11 stereoisomers of farnesylacetone, the authors carried out low-temperature sulf…
This paper reports the preparation and characterization of two positional isomers of chloroamminemethionineplatochloride, [NH3ClPtMtH]Cl, a type of platinum(II) complex with one chelated methionine ligand and two different monodentate ligands. The synthesis exploits the different trans influences of…
This paper examines the mechanism by which organic acids accelerate free-radical formation during hydroperoxide decomposition in the liquid-phase oxidation of paraffin hydrocarbons. Using oxidized n-decane containing hydroperoxides, caproic acid additions, inhibition by alpha-naphthol, and kinetic m…
This paper examines equilibria in the reactions of sodium and lithium with diphenyl and naphthalene in electron donor solvents, focusing on how cation solvation controls radical anion and dianion formation. Equilibrium constants, enthalpies, and entropies were obtained spectrophotometrically for sod…
This paper describes the use of phenylboronic acid as a temporary protecting group for the 2′,3′-cis-glycol of adenosine in the selective synthesis of adenosine 5′-monophosphate. The authors prepare crystalline 2′,3′-phenylboronate adenosine by azeotropic removal of water in pyridine, phosphorylate …
This study examines the stability and reaction pathways of β-(N-ethylenimino)ethylsilanes under elevated temperatures and in the presence of nucleophilic and electrophilic reagents, with attention to possible β-cleavage of the silicon-carbon bond and transformations of the ethylenimine ring. Triethy…
The paper determines the crystal structure of dumortierite, an orthorhombic aluminum borosilicate, using single crystal X-ray diffraction data from Weissenberg photographs and analysis of Patterson and electron-density projections. Systematic absences, absence of piezoelectricity, statistical tests,…
tert-Butyl β-(trimethylsilyl)perpropionate was synthesized from β-(trimethylsilyl)propionyl chloride and the sodium salt of tert-butyl hydroperoxide in yields up to 60 percent, and its decomposition was examined to assess the behavior of silicon-containing radicals. Reactions in cumene, chlorobenzen…
This study examines the spectropolarimetric behavior of optically active alpha-phenylethylamides of pyridinecarboxylic acids, focusing on how the position of the carboxamide group in the pyridine ring affects optical rotatory dispersion. The authors synthesized amides of picolinic, nicotinic, isonic…
This study examines the synthesis and reactivity of phosphorus-containing hydrazo and azo compounds, focusing on tetraalkyl esters of hydrazodiphosphonic and azodiphosphonic acids. Tetraalkyl hydrazodiphosphonic esters with ethyl, butyl, hexyl, and octyl groups were prepared from dialkyl chlorophosp…
The study examines the structure and thermal decomposition of cyclic and linear polymers formed from dimethyldichlorosilane or dimethyldichlorogermane with lithium in tetrahydrofuran. Infrared and NMR spectroscopy, mass spectrometry, microreactor gas-liquid chromatography, and thermogravimetry are u…
The paper compares the reactivity and stability of the three-membered ring in norcarane, substituted norcaranes, and related cyclopropane derivatives under electrophilic addition of mercuric acetate in methanol. Using the extent of reagent consumption as a measure of relative reactivity, the authors…
This paper examines the synthesis and catalytic hydrogenation of 2-phenylethylenimine as a carbon-substituted ethylenimine, motivated by earlier observations that related aziridine rings undergo hydrogenolysis under mild conditions. The authors develop a preparation from styrene oxide through amino …
This study examines chlorine isotopic exchange in Koss-type platinum(II) salts, specifically potassium trichloroammineplatinate and its pyridine analogue, in order to test whether coordinated chlorine ligands are kinetically equivalent. Exchange experiments with radioactive chloride were analyzed fr…
This paper addresses the difficulty of assigning structures to isomeric dialkylbenzenes when boiling points, elution order, or conventional gas chromatographic retention relationships are insufficiently diagnostic. The authors propose using a coefficient defined as the ratio of relative retained vol…
This study examines the radiation-induced addition of molecular nitrogen to simple perchlorocarbons, chiefly tetrachloroethylene and carbon tetrachloride, chosen to simplify product interpretation and exclude nitrogen-hydrogen-containing starting structures. Purified samples were irradiated with cob…
The study examines the kinetics of catalytic dehydrogenation of butane to butylenes over an alumina, chromia, potassium catalyst using a flow circulation method with a moving catalyst bed, designed to reduce errors associated with variable catalyst activity. Experiments varying space velocity, conve…
This paper addresses the separation of 4-vinylpyridine from mixtures of pyridine bases obtained in the catalytic dehydrogenation of 4-ethylpyridine, a process complicated by close boiling points and the tendency of vinyl compounds to polymerize during rectification. The authors propose isolating 4-v…
This paper examines anomalous temperature dependences in the low-temperature photopolymerization of styrene, including cases without a sensitizer and sensitized systems using diacetyl. From rate measurements, inhibition experiments with quinone, viscosity studies of polymer solutions, and comparison…
This paper examines the formation of large crystalline structures in isotactic polypropylene crystallized from very dilute decalin solutions under controlled solvent evaporation. Using electron microscopy, the authors describe fibrillar dendrites composed of 10 to 20 Å fibrils, interpreted as bundle…
This paper reports the preparation and preliminary characterization of ethylenediamine tetrammine complexes of tetravalent palladium, a class previously little known because of the ready reduction of Pd(IV) in solution. Oxidation of divalent palladium ethylenediamine complexes with nitric acid, chlo…
This study examines lactim and lactam tautomerism in free molecules by measuring infrared spectra of vapors, using alpha-pyridone and delta-valerolactam, including N-deuterated derivatives, as representative unsaturated and saturated lactams. The authors recorded O-H, N-H, O-D, and N-D stretching ba…
The study examines the structures of the bisbenzylisoquinoline alkaloids thalmine and thalmidine isolated from Thalictrum minus. Using infrared spectra, alkylation, acetylation, sodium in liquid ammonia cleavage, Hofmann degradation, and oxidative transformations, the authors identify several cleava…
This study applies Mössbauer spectroscopy to a series of tetravalent and divalent organotin derivatives of barenes in order to evaluate how barenyl substituents affect the electronic environment of the tin nucleus. Measurements of isomer shifts and quadrupole splittings at 77 K show that barenyl gro…
The paper reports an X-ray crystallographic determination of the structure of alpha-trichloromethyl-N-methylolethylenimine, C4H6ONCl3, an ethylenimine derivative described as an active chemical mutagen. Unstable single crystals grown from ether were protected from sublimation and examined by Weissen…
This paper analyzes how slow nonradical reactions affect the existence and stability of stationary regimes in chain thermal processes with radical production and consumption. A nonlinear reaction diffusion model with heat release, reactant depletion, and small zeroth order radical generation is redu…
This paper examines whether complete esters of phosphorous acid bearing saturated radicals can undergo thermal rearrangement to alkylphosphinic acid esters, in light of conflicting earlier reports. The authors heat purified lower trialkyl phosphites and compare them with unpurified materials and mix…
The paper addresses conflicting reports on the symmetry and crystal chemistry of rinkite, a mineral of the seidozerite and rinkite group with broad isomorphic substitutions. Using X-ray goniometer data from Greenland rinkite, Patterson projections, superposition methods, and refinement against zero-…
The paper investigates the quasi-line absorption and fluorescence spectra of tetrabenzoporphin in order to clarify how benzo substitution affects the electronic and vibrational structure of the porphin ring. Using purified tetrabenzoporphin in hydrocarbon matrices at low temperature under Shpolskii-…
This paper investigates the synthesis of more soluble heat-resistant polybenzoxazoles by polycyclization of dioxydiamines with diphenyl esters of sebacic, isophthalic, and terephthalic acids. The authors use dioxydiamines containing flexible or substituted bridging groups, especially 2,2-bis-(3-amin…
This study expands the range of silicacyclobutane monomers by synthesizing several carbofunctional 1-methyl-1-silacyclobutanes bearing cyanoalkyl, vinyl, and styryl substituents, as well as a spiro silicon hydrocarbon. The compounds were prepared by hydrosilylation and Grignard reactions, characteri…
This paper examines 1-phenyl-3-methyl-4-benzoylpyrazolone-5 as an organic reagent for extracting inner-complex compounds of elements from acidic and neutral aqueous solutions. The authors determined acid dissociation and distribution constants and studied extraction of elements including plutonium(I…
This paper discusses the mechanism of unit formation in stereospecific diene polymerization catalyzed by transition metal complexes, especially systems modeled by pi-allyl and crotyl nickel structures. It argues that monomer incorporation can be interpreted through alternative orientations of 1,4 co…
This paper examines the synthesis, purification, and thermal disproportionation of trifluoroborazane and several methyl and ethyl derivatives containing B,N bonds. The authors describe a simplified preparation from boron trifluoride etherate and amines without low temperature conditions, obtaining h…
This paper investigates the infrared spectra of radical anions of naphthalene, anthracene, tetracene, and pentacene formed by reaction with potassium in tetrahydrofuran under vacuum. Spectra of undeuterated and fully deuterated naphthalene and anthracene are used to assign radical-anion bands and co…
This paper develops a thermodynamic treatment of ion exchange equilibria under isopiestic conditions, considering the ion exchanger as a solid solution of swollen resinates and deriving relations for exchange constants and activity coefficients for ions of unequal valence. The method combines isopie…
This paper investigates the mechanism of the polymorphic transformation of graphite into diamond under high pressure and high temperature, with particular attention to whether conversion occurs through dissolution in a metal catalyst or by direct lattice reconstruction. The authors use pyrolytic gra…
This paper examines the stereospecific action of heterogeneous magnesium catalysts in the polymerization of propylene oxide, with emphasis on magnesium oxalate and optically active magnesium tartrate. Drawing on polymerization data, optical rotation measurements, solvent effects, catalyst hydration,…
The paper examines how adsorbed hydrogen affects cyclohexane dehydrogenation on platinum, a question linked to differing views on whether hydrogen desorption or hydrocarbon adsorption limits dehydrogenation. Using gas-phase measurements of the catalyst potential on a platinum film at different tempe…
This paper examines whether an upper pressure limit for thermal self-ignition can occur in a chain reaction without branching, contrary to the usual expectation that such limits require chain branching. A hypothetical one-center gas reaction in a spherical reactor is analyzed, with radical initiatio…
This paper describes the synthesis of the little studied carbonyl monomer alpha-ethoxyacrolein using a Mannich reaction of ethoxyacetaldehyde with formaldehyde in the presence of secondary amine hydrochlorides, followed by decomposition of the Mannich base hydrochloride. The authors examine reaction…
This paper examines the reaction of hexafluoroacetone with triethyl phosphite and addresses conflicting reports on whether the primary product is a cyclic phosphorane or 2-ethoxyperfluoropropylene. The authors show experimentally that the cold reaction forms the cyclic phosphorane in both excess and…
The paper examines the use of disproportionation reactions as a synthetic route to organosilicon polymers, focusing on polyphenylenesilanes derived from bis, alkylalkoxysilyl benzenes. Heating these monomers with catalytic nucleophilic reagents such as potassium hydroxide or sodium ethylate led to e…
This study examines the mechanism of structure formation during gelation in purified isoelectric gelatin solutions. Gel strength was followed through the limiting static shear stress using a tangentially displaced plate method, while optical rotation measurements were used to relate mechanical devel…
This study examines the long-disputed nature of isomerism in diazocyanides, contrasting the earlier geometrical interpretation with a structural nitrile, isonitrile formulation. The authors compare chemical behavior and infrared spectra for three pairs of substituted phenyldiazocyanides, measuring a…
