Showing papers in "Russian Chemical Bulletin in 1978"
TL;DR: In this article, the thermodynamic parameters for the complexing of SnCl4 and organotin chlorides with organophosphorus donors satisfy the general linear ΔH° vs ΔS° relation applying to donor-acceptor complexes.
Abstract: 1.
The thermodynamic parameters for the complexing of SnCl4 and organotin chlorides with organophosphorus donors satisfy the general linear ΔH° vs ΔS° relation applying to donor-acceptor complexes.
2.
The energy of the P → Sn bond in the (C2H5)nSnCl4−n · (C4H9)3P complexes falls off as the number of Cl atoms in the acceptor molecule is reduced.
3.
The energy of the P → Sn bond in the SnCl4 · R1R2R3P complexes, and of the O → Sn bond in the SnCl4 · R1R2R3PO complexes, are closely dependent on inductive and resonance effects from the substituents R1, R2, and R3. The sensitivity of the coordination centers to substituent effects is higher in the phosphines than in the phosphine oxides.
41 citations
TL;DR: The carboxylation of ethylene with CO2 in the presence of tris (triphenylphosphine) rhodium chloride at 700 atm and 180° gave propionic acid, ethanol, and ethyl propionate in respective yields of 38.4, 24.3, and 11.2%, with an ethylene conversion of 91.4%.
Abstract: The carboxylation of ethylene with CO2 in the presence of tris (triphenylphosphine) rhodium chloride at 700 atm and 180° gave propionic acid, ethanol, and ethyl propionate in respective yields of 38.4, 24.3, and 11.2%, with an ethylene conversion of 91.4%.
29 citations
TL;DR: In this article, the acid dissociation constants of these compounds and the stability constants of their complexes with Ca2+, Co2+, and Cu2+ ions were measured and compared.
Abstract: 1.
We have synthesized new amino-substitutedα-hydroxyalkylidenediphosphonic acids.
2.
We have measured the acid dissociation constants of these compounds and the stability constants of their complexes with Ca2+, Co2+, and Cu2+ ions.
12 citations
TL;DR: A study of the effect of the reactor surface (stainless steel and Teflon) on the oxidation of hexfluoropropylene has been made in this article, showing that the increase in yields of carbonylfluoride and trifluoroacetylfluorside which accompanies passage to the metal reactor is due to metal catalysis of the decomposition of alkoxy- and alkylperoxy radicals at the C-C bond.
Abstract: 1.
A study has been made of the effect of the reactor surface (stainless steel and Teflon) on the oxidation of hexfluoropropylene. In the Teflon reactor, the hexafluoropropylene reacts with surface peroxide radicals, the result being that ester and peroxide groups are introduced into the polymeric Teflon molecules. Stainless steel catalyzes the formation of hexafluoroacetone and various oligomeric products: CF3O(CF2O)n·CF2OCF2COF, and CF3O(CF2O)m· CF2OCOF.
2.
The increase in yields of carbonylfluoride and trifluoroacetylfluoride which accompanies passage to the metal reactor is due to metal catalysis of the decomposition of alkoxy- and alkylperoxy radicals at the C-C bond.
9 citations
TL;DR: In this article, the authors measured the rate constant of the reaction NH2+NO → products and the probability of the effective destruction of NH2 on quartz using the intraresonator laser spectroscopy method.
Abstract: 1.
The intraresonator laser spectroscopy method can be used successfully to study the rate constants of gas-phase chemical reactions.
2.
We measured the rate constant of the reaction NH2+NO → products and the probability of the effective destruction of NH2 on quartz. The constant k1 is independent of the total pressure in the range 0.1–1 torr.
8 citations
TL;DR: The N,N'-disubstituted amidines are capable of adding to the multiple bonds of aldehydes and isocyanates to form the corresponding six-membered cyclic coordination compounds of boron.
Abstract: 1.
Dialkylborylamidines, which have a chelate structure or are equilibrium mixtures of a chelate and an open form, have been synthesized from N,N'-disubstituted amidines.
2.
N-Dialkylboryl-N,N'-disubstituted amidines are capable of adding to the multiple bonds of aldehydes and isocyanates to form the corresponding six-membered cyclic coordination compounds of boron.
7 citations
TL;DR: There is a range of temperatures and pressures in which dilution with hydrogen, a reaction product, will increase the rate of growth on diamond seed crystals from methane and ethane as discussed by the authors.
Abstract: There is a range of temperatures and pressures in which dilution with hydrogen, a reaction product, will increase the rate of growth on diamond seed crystals from methane and ethane.
7 citations
TL;DR: Some five and seven-membered binuclear o-carborane heterocycles, in which the heteroatoms are P, As, Si, and Ge, were obtained from bis-o-Carborane and 1,2-bis(o -carboranyl)ethane as mentioned in this paper.
Abstract: Some five- and seven-membered binuclear o-carborane heterocycles, in which the heteroatoms are P, As, Si, and Ge, were obtained from bis-o-carborane and 1,2-bis(o-carboranyl)ethane.
6 citations
TL;DR: In this paper, the synthesis of 5-methylphenylamino and 5-diphenylaminooxazole from α-N-acylated amino acids and secondary amines of the type C6H5NHR in the presence of dehydrating agents has been carried out.
Abstract: 1.
The synthesis of 5-methylphenylamino- and 5-diphenylaminooxazole fromα-N-acylated amino acids and secondary amines of the type C6H5NHR in the presence of dehydrating agents has been carried out.
2.
According to the13C NMR and PMR data, the introduction of 5-C6H5NR and (C6H5)2N groups into the oxazole ring results in a significant increase in the screening of the C4 and C2 carbon atoms and the unscreening of the C5 carbon atom.
6 citations
TL;DR: In this article, the donor-acceptor interaction between the boron atom and the trigonal nitrogen atom of the chelate ring was achieved by reacting boronal halides with dialkylborylimidoylamidinates.
Abstract: 1.
Diphenylborylimidoylamidinates and dialkylborylimidoylamidinates substituted at the nitrogen atom were synthesized.
2.
The hydrochloride and perchlorate salts of dialkylborylimidoylamidinates, which are a variant of boronium salts, were prepared. Complexes in which a donor-acceptor interaction is accomplished between the boron atom of a boron halide and the trigonal nitrogen atom of the chelate ring were prepared by reacting boron halides with the dialkylborylimidoylamidinates.
5 citations
TL;DR: In this paper, an equation for the dilatometric curve that contains two parameters, namely the omnidirectional compression coefficient and a constant that is proportional to the standard chemical potential of the adsorbate in a given vacant solution, was derived.
Abstract: 1.
Independent of the form of the adsorption isotherm equation, the ratio of the relative adsorption deformation to the adsorption is a linear function of the logarithm of the equilibrium pressure.
2.
An equation was obtained for the dilatometric curve that contains two parameters, namely the omnidirectional compression coefficient and a constant that is proportional to the standard chemical potential of the adsorbate in a given vacant solution.
3.
The adsorption isotherm and dilatometric curves were measured for a krypton-granulated zeolite CaA system in the temperature range from 153 to 198°K, and it was shown that the experimental data coincide well with the derived equations.
TL;DR: The reaction of the Na salts of dialkylphosphorous acids with nitriles leads to the dialkyl esters of N-(1-dialkylphosphonylalkyl) amidophosphoric acids, whose formation proceeds via the aminophosphonate-amidophosphate rearrangement of the sodium derivatives of bis(dialkkliphosphonyls)alkylamines as discussed by the authors.
Abstract: The reaction of the Na salts of dialkylphosphorous acids with nitriles leads to the dialkyl esters of N-(1-dialkylphosphonylalkyl) amidophosphoric acids, whose formation proceeds via the aminophosphonate-amidophosphate rearrangement of the sodium derivatives of bis(dialkylphosphonyl)alkylamines.
TL;DR: In this article, a method has been developed for the synthesis of organogold compounds of the aryl, alkenyl, cymantrenyl, and heterocyclic series from organomercury compounds.
Abstract: 1.
A method has been developed for the synthesis of organogold compounds of the aryl, alkenyl, cymantrenyl, and heterocyclic series from organomercury compounds.
2.
Either binuclear cationic complexes of gold with the general formula [R(AuPPh3)2]BF4 or monogold organic compounds with the general formula RAuPPh3 form, depending on the nature of the radial in the organomercury compound.
3.
Previously unknown organogold compounds with the general formula RAuPPh3 have been obtained from the binuclear cationic complexes of gold under the action of triphenylphosphine.
TL;DR: In this paper, it was shown that 2,6-dimethyl-3,5-dicarbethoxy-1,4-dihydropyridine and its 4-substituted alkyl derivatives are easily converted to the corresponding pyridines under the influence of homogeneous Pd catalysts.
Abstract: 1.
We were the first to study the dehydrogenation of 1,4-dihydropyridines using catalytic amounts of homogeneous Pd catalysts and it was shown that 2,6-dimethyl-3,5-dicarbethoxy-1,4-dihydropyridine and its 4-substituted alkyl-(CH3-C4H9) and aryl- (C6H5, o-C6H4OH, CH=CH-C6H5, p-C6H4-OCH3) derivatives are easily converted to the corresponding pyridines under the influence (10 h, 100°) of the catalyst: Pd(acac)2-P(C4H9)3-Al(C2H5)3-CF3CO2H (1∶3∶3∶10).
2)
When substituted 1,4-dihydropyridines are dehydrogenated in the presence of 1,5-cyclooctadienes the latter undergo simultaneous selective hydrogenation to the corresponding cyclooctenes.
TL;DR: Some palladium(I) carbonyl tetranuclear complexes were synthesized based on IR spectral and x-ray structure analysis data, which contain two long and two short Pd-Pd bonds with two carbonyls and two carboxylate bridges as mentioned in this paper.
Abstract: Some palladium(I) carbonyl tetranuclear complexes were synthesized, which, based on the IR spectral and x-ray structure analysis data, contain two long and two short Pd-Pd bonds with two carbonyl and two carboxylate bridges
TL;DR: The transmetallation method has been used to measure equilibrium acidities of P(O)H and P(S)H-acids of various structures in dimethylsulfoxide solution and relative to 9-phenyl-fluorene.
Abstract: 1.
The transmetallation method has been used to measure equilibrium acidities of P(O)H-and P(S)H-acids of various structures in dimethylsulfoxide solution and relative to 9-phenyl-fluorene.
2.
The effect of the substituent at the P atom on the pK value for the P(O)H-acid can be described by linear correlation relations in the σφ and σ* constants. The diarylphosphinous acids cannot be fitted into such correlations because of p,π coupling in their anions.
3.
The acidity of the P(S)H-acids is some nine orders higher than that of the phosphoryl analogs.
TL;DR: In this article, a method for the N-nitrosation of secondary amines using N2O4 complexes in combination with tertiary amines or pyridine was proposed.
Abstract: A method was proposed for the N-nitrosation of secondary amines using N2O4 complexes in combination with tertiary amines or pyridine.
TL;DR: In this paper, two parallel reactions are involved in hydrogen elimination under the conditions of their experiments, one reversible and the other irreversible, the latter leading to the liberation of 2 moles of H2 through an autocatalytic first-order process.
Abstract: 1.
Decaborane(12) diammoniate decomposes at a measurable rate at 180–225°C, hydrogen being eliminated. Decomposition occurs nonuniformly over the entire B10H12(NH3)2 crystal body.
2.
Two parallel reactions are involved in hydrogen elimination under the conditions of our experiments, one reversible and the other irreversible, the latter leading to the liberation of 2 moles of H2 through an autocatalytic first-order process.
TL;DR: In this article, it was shown that polyunsaturated amines can be obtained by the reaction of allylamines with butadiene in the presence of Ni-and Pd-containing complex catalysts.
Abstract: 1.
It was shown that polyunsaturated amines can be obtained by the reaction of allylamines with butadiene in the presence of Ni- and Pd-containing complex catalysts.
2.
A convenient and simple method was developed for the preparation of triallylamine from diallylamine.
TL;DR: In this article, the conformational free energy of a phenyl substituent on a tri-and tetracoordinated phosphorus atom in a 2,4,6-trimethyl-1,3,5-dioxaphosphorinane ring was determined.
Abstract: We determined the conformational free energy of a phenyl substituent on a tri- and tetracoordinated phosphorus atom in a 2,4,6-trimethyl-1,3,5-dioxaphosphorinane ring.
TL;DR: In this article, it was shown that the phosphine complexes of trans-styryl gold are formed from trans, trans-distyrylmercury, and triferrocenylphosphine ligands.
Abstract: 1.
Some binuclear cationic complexes of styrylgold with triphenyl- and triferrocenylphosphine ligands were obtained.
2.
It was shown that the phosphine complexes of trans-styrylgold are formed from trans, trans-distyrylmercury.
TL;DR: There is a linear correlation between the band energies of the first intervalence transition and the half-wave potentials for reduction in the isostructural heteropolyanions with equal charge, XM11ZO40n− as mentioned in this paper.
Abstract: There is a linear correlation between the band energies of the first intervalence transition and the half-wave potentials for reduction in the isostructural heteropolyanions with equal charge, XM11ZO40n−. The intervalence transition is due to excitation of an electron from the orbital localized on the reduced atom to orbitals localized on atoms in the coordination sphere. The authors suggest that the less the delocalization of the electrons over the whole structure, the greater will be the intensity of the intervalence transition.
TL;DR: In this paper, a method was proposed for the synthesis of perfluoroalkanesulfenyl chlorides by reacting fluorocarbanions with dialkylaminos sulfenylchlorides and subsequent replacement of the dialkylino group by chlorine.
Abstract: 1.
Fluorocarbanions, generated by the addition of fluoride anion to the multiple bond of perfluoropropylene, perfluoroisobutylene, and methyl perfluoromethacrylate, are sulfenylated by ethane-, benzene-, and dialkylaminosulfenyl chlorides to give polyfluoroalkyl sulfides and sulfenamides.
2.
Sulfenyl chlorides with electron-acceptor substituents chlorinate fluorocarbanions.
3.
A method was proposed for the synthesis of perfluoroalkanesulfenyl chlorides by reacting fluorocarbanions with dialkylaminosulfenyl chlorides and subsequent replacement of the dialkylamino group by chlorine.
TL;DR: The donor-acceptor complexes obtained are modified Lewis acids as discussed by the authors, in which the water molecule is coordinated by the aluminum atom, which explains their selectivity in electrophillc reactions.
Abstract: 1.
In the reaction of (C2H5)2AlCl and C2H5AlCl2 with water (1∶1 molar ratio) under mild conditions, donor-acceptor complexes are formed, in which the water molecule is coordinated by the aluminum atom. Sesquiethylaluminum chloride in its reaction with water behaves as a mixture of monochloro and dichloro derivatives.
2.
Benzene and toluene increase the tendency of ethylaluminum chlorides towards hydrolysis and, in the case of C2H5AlCl2 the Al-Cl2 and Al-C bonds are cleaved, whereas only the Al-C bond is cleaved in (C2H5)AlCl.
3.
The reaction of (C2H5)2AlCl and C2H5AlCl2 with water in diethyl ether is accompanied by the hydrolysis of Al-C bonds and leads to the etherates of the corresponding alumoxanes.
4.
The donor-acceptor complexes obtained are modified Lewis acids. The low acidity of these complexes explains their selectivity in electrophillc reactions.
TL;DR: In this article, a study of the kinetics of the photosensitized oxidation of sterically hindered phenols with para-substituents, and ofα- andβ-naphthols, in n-butanol, and rate constants have been determined for the reactions of these compounds with singlet oxygen.
Abstract: 1.
A study has been made of the kinetics of the photosensitized oxidation of sterically hindered phenols with para-substituents, and ofα- andβ-naphthols, in n-butanol, and rate constants have been determined for the reactions of these compounds with singlet oxygen. The data obtained indicate that the primary photochemical act involves electron transfer from the phenol to the1O2.
2.
It has been shown that there is a correlation between the kinetic constant kr and kRO 2, the constant characterizing the reactivity of the phenol with respect to the peroxide radical. The existence of such correlation opens the possibility of determining kRO 2 from the value of kr.
TL;DR: In this article, molybdenum or iron oxides were added to PdCl2 to increase its catalytic activity in the carbonylation of 2,4-dinitrotoluene by carbon monoxide.
Abstract: Addition of molybdenum or iron oxides to PdCl2 increases its catalytic activity in the carbonylation of 2,4-dinitrotoluene by carbon monoxide. Increased pressure increases the yield of 2,4-diisocyanatotoluene to ∼90%.
TL;DR: In this article, the formation of 2,4,6-trifluoro-3,5-dichloropyridine by the reaction of pentachlorOPyridine with KF in MeCN, in the presence of catalytic amounts of an 18-crown 6-ester, proceeds at considerably lower temperatures and is not complicated by the reverse reaction.
Abstract: The formation of 2,4,6-trifluoro-3,5-dichloropyridine by the reaction of pentachloropyridine with KF in MeCN, in the presence of catalytic amounts of an 18-crown 6-ester, proceeds at considerably lower temperatures and is not complicated by the presence of the reverse reaction.
TL;DR: The complexing results from ligand substitution in the reaction with 3,6-di-tert-butyl-orthoquinone, and by coordination on the vacant orbital of the central ion of the.
Abstract: 1.
ESR methods have been used to show the formation of paramagnetic complexes of certain transitionmetal acetylacetonates with orthoquinones.
2.
The complexes of the zirconium and hafnium acetylacetonates are fundamentally different in structure; complexing results from ligand substitution in the reaction with 3,6-di-tert-butylorthoquinone, and by coordination on the vacant orbital of the central ion in the reaction with 3,6-di-tert-butyl-2-hydroxyphenoxyl.
3.
Complexing with zirconium acetylacetonate leads to a marked increase in the acidity of the hydroxyl group proton in 3,6-di-tert-butyl-2-hydroxyphenoxyl.
TL;DR: In this article, the Pd/SiO2 catalyst for the carbonylation of ethylene with CO was proposed and the catalytically active form is Pd(O).
Abstract: In deposited Pd/SiO2 catalyst for the carbonylation of ethylene with CO the catalytically active form is Pd(O).