Showing papers in "Russian Chemical Reviews in 1974"
TL;DR: The available literature data up to 1973 on the electronic effects of fluorine-containing substituents are considered and discussed in the review as discussed by the authors, which includes 149 references including 149 references from the reference set.
Abstract: The available literature data up to 1973 on the electronic effects of fluorine-containing substituents are considered and discussed in the review. The bibliography includes 149 references.
143 citations
TL;DR: In this article, a review of the Ullmann condensation as the most important method for the synthesis of aromatic ethers is presented, and the available information about the dependence of reactivity of the reactants on structure and the reaction mechanism is examined and the experimental condensation conditions are discussed.
Abstract: The review deals with the Ullmann condensation as the most important method for the synthesis of aromatic ethers. The available information about the dependence of the reactivity of the reactants on structure and the reaction mechanism is examined and the experimental condensation conditions are discussed. The bibliography includes 241 references.
96 citations
TL;DR: In this paper, the methods of preparation of aminoalkyl compounds of phosphorus (by transformation of functional groups and by amino-alkylation of tervalent phosphorus compounds) and their physical and chemical properties are presented and the practical applications of substances of this type are briefly described.
Abstract: Data on the methods of preparation of aminoalkyl compounds of phosphorus (by transformation of functional groups and by aminoalkylation of tervalent phosphorus compounds) and their physical and chemical properties are presented and the practical applications of substances of this type are briefly described The bibliography includes 528 references
73 citations
TL;DR: The literature data on acetylene cyclo-oligomerization and polymerisation reactions in the presence of transition metal compounds are reviewed in this article, including catalytic reactions leading to the synthesis of benzene and cyclo octatetraene derivatives and linear polymers.
Abstract: The literature data on acetylene cyclo-oligomerisation and polymerisation reactions in the presence of transition metal compounds are reviewed. Both catalytic reactions leading to the synthesis of benzene and cyclo-octatetraene derivatives and linear polymers and cyclo-oligomerisation reactions leading to the formation of organometallic compounds are considered. Modern ideas on the mechanism of acetylene cyclo-oligomerisation and polymerisation reactions are discussed in detail. The bibliography includes 362 references.
49 citations
TL;DR: In this paper, the most important published data on the composition and structure of aluminate ions in solutions of different concentrations and pH values are systematised and analyzed, and the views of various workers on the types of interaction present in aluminate solutions are discussed.
Abstract: The most important published data on the composition and structure of aluminate ions in solutions of different concentrations and pH values are systematised and analysed. The views of various workers on the types of interaction present in aluminate solutions are discussed. The significance of different hypotheses and models of mononuclear and polynuclear aluminate ions is examined in the light of the results of recent physicochemical investigations. The bibliography includes 154 references.
43 citations
TL;DR: In this article, the results of studies in the last decade on the reduction of molecular nitrogen in aprotic and protic media are presented, the products, intermediate complexes, and mechanisms of these reactions are considered.
Abstract: The review presents the results of studies in the last decade on the reduction of molecular nitrogen in aprotic and protic media. The products, intermediate complexes, and mechanisms of these reactions are considered. The relation between the mechanisms of the N2 reduction reactions discovered recently and the mechanism of biological nitrogen fixation is discussed. The bibliography includes 161 references.
42 citations
TL;DR: In this paper, the principal aspects of Diels-Alder synthesis with six membered heterocyclic dienes (2-pyrones and 2-pyridones) as well as the latest data on the endo-exo selectivity of this reaction are considered.
Abstract: The principal aspects of Diels–Alder synthesis with six membered heterocyclic dienes (2-pyrones and 2-pyridones) as well as the latest data on the endo–exo selectivity of this reaction are considered. The bibliography includes 121 references.
41 citations
TL;DR: In this paper, a review deals with the new rapidly developing field of homogeneous catalysis and coordination chemistry, namely with reactions involving hydrogen transfer from organic compounds to transition metal complexes accompanied by the dissociation of a C-H bond and the formation of a metal-hydrogen bond.
Abstract: The review deals with the new rapidly developing field of homogeneous catalysis and coordination chemistry, namely with reactions involving hydrogen transfer from organic compounds to transition metal complexes accompanied by the dissociation of a C–H bond and the formation of a metal–hydrogen bond. Particular attention has been devoted to catalytic reactions in which transition metal compounds serve as catalysts of hydrogen transfer and of the reduction of organic compounds by the C–H bonds of other organic molecules. The bibliography includes 177 references.
36 citations
TL;DR: In this paper, a detailed analysis is made of the macroscopic phenomena accompanying the reversible solution?gel transition, as well as the strength, rubber-elastic, plastic, and relaxation properties of gels.
Abstract: A gel is taken to be a polymer?solvent system in which the polymer, present at very low concentration, forms a quite stable three-dimensional network in the solvent. Consideration is given to the properties of gels in which the network is formed both by chemical and by physical bonds; attention is paid mainly to the second group of gels, in which variation in temperature produces a reversible transition between gel and solution. Existing views on the thermodynamic nature and structure of gels are subjected to critical analysis, and specific gel-forming systems are examined. A detailed analysis is made of the macroscopic phenomena accompanying the reversible solution?gel transition, as well as the strength, rubber-elastic, plastic, and relaxation properties of gels. A list of 399 references is included.
33 citations
TL;DR: A little more than 20 years have elapsed since the discovery of ferrocene (dicyclopentadienyliron) and during this period its chemistry has developed quite extensively as discussed by the authors.
Abstract: A little more than 20 years have elapsed since the discovery of ferrocene (dicyclopentadienyliron) and during this period its chemistry has developed quite extensively. The present authors have seen the beginning of practical studies on the applications of ferrocene and its compounds. The review does not deal with the applications of ferrocene-containing polymers. The bibliography includes 81 references.
29 citations
TL;DR: In this article, the Fischer synthesis of indoles and the recently discovered rearrangement of O-phenyl ethers of oximes, which takes place under similar conditions and leads to the formation of benzofurans, are assessed from the same standpoint.
Abstract: Both the Fischer synthesis of indoles and the recently discovered rearrangement of O-phenyl ethers of oximes, which takes place under similar conditions and leads to the formation of benzofurans, are assessed in the review from the same standpoint. A number of studies published recently altered the ideas held for a long time concerning the mode of cyclisation of the arylhydrazones of asymmetric ketones into indoles. It was believed previously that CH3, CH2, and CH groups in the α-position in the carbonyl fragment constitute a series in which the capacity for cyclisation increases. However, it has been found that the acidity of the medium plays a very significant role in determining the mode of cyclisation and can actually reverse it. The concepts put forward to account for this finding are examined critically and general ideas are developed which, in the author's view, explain satisfactorily the influence of the pH of the medium and of certain other factors on the mode of cyclisation of both arylhydrazones and O-aryloximes. The bibliography includes 109 references.
TL;DR: In this paper, a systematic account is given of the behavior of substituents located at a bridgehead, and of the differing reactivities of?- and?-positions in the aromatic rings on nucleophilic and electrophilic substitution.
Abstract: Information is presented on the preparation of triptycene, its homologues, and substituted derivatives. The spectroscopic, X-ray, optical, and other physical properties of these compounds are discussed. A systematic account is given of the behaviour of substituents located at a bridgehead, and of the differing reactivities of ?- and ?-positions in the aromatic rings on nucleophilic and electrophilic substitution. Reactions involving opening of the bridge system, the polarographic reduction of triptycenequinones, and the catalytic hydrogenation of triptycene are considered. The list of references contains 247 items.
TL;DR: In this article, the possibilities of membrane catalysts to increase the rate and selectivity of reactions, to obtain incomplete hydrogenation products, and to decrease the competition between the adsorption of the substance hydrogenated and hydrogen are demonstrated.
Abstract: The reactions of different classes of hydrocarbons on catalysts selectively permeable with respect to hydrogen are considered. The possibilities of membrane catalysts to increase the rate and selectivity of reactions, to obtain incomplete hydrogenation products, and to decrease the competition between the adsorption of the substance hydrogenated and hydrogen are demonstrated. The coupling of reactions on membrane catalysts whereby it is possible to achieve a reaction, which does not occur spontaneously, as a result of the decrease of the free energy of the coupled reaction when the substance common to the two reactions passes through the membrane catalyst is discussed. The bibliography includes 135 references.
TL;DR: In this paper, the physicochemical and research techniques which have led to the current views on the structures of heteropolycompounds (a large class of complexes) are briefly considered, and the possibilities which arise on substitution of one or several metal atoms in the coordination sphere of the heteropoly compound are examined on the basis of structural considerations.
Abstract: Different types of heteropolycompounds, which are formed in solutions and can be isolated from the latter in a crystalline state, have been analysed and classified on the basis of the results of latest X-ray diffraction studies. The physicochemical and research techniques which have led to the current views on the structures of heteropolycompounds (a large class of complexes) are briefly considered. The possibilities which arise on substitution of one or several metal atoms in the coordination sphere of the heteropolycompound are examined on the basis of structural considerations. The principal trends and problems in the chemistry of heteropolycompounds are discussed. The bibliography includes 191 references.
TL;DR: In this paper, the kinetics, mechanism, and driving forces of alkyl halides and several inorganic halides, induced by metal ions M+ in aqueous media, are summarised.
Abstract: Investigations of the kinetics, mechanism, and driving forces of hydrolyses of alkyl halides and several inorganic halides, induced by metal ions M+ in aqueous media, are summarised. Relations between the rate and the Lewis acidity of M+ are examined, together with models of M+?SN1 and M+?SN2 reactions. A list of 163 references is included.
TL;DR: In this paper, the authors summarized results published up to 1972 on the kinetics and the mechanism of the reactions of silicon and germanium with halogens, their hydrides, and organic derivatives.
Abstract: Results published up to 1972 inclusive on the kinetics and the mechanism of the reactions of silicon and germanium with halogens, their hydrides, and organic derivatives are summarised. The kinetics and the mechanism of formation of the most important organic and halogenated derivatives of silicon and germanium, which have found wide industrial application, are discussed. Published data are analysed in the light of modern views on the progress of heterogeneous catalytic reactions. A list of 163 references is included.
TL;DR: In this article, the principal advances in the electrochemistry of selenium and tellurium were discussed, and problems concerning the kinetics and mechanisms of the cathodic reduction of the two elements to different valence states and their anodic oxidation in aqueous and non-aqueous solutions are discussed.
Abstract: The review deals with the principal advances in the electrochemistry of selenium and tellurium. Problems concerning the kinetics and mechanisms of the cathodic reduction of selenium and tellurium to different valence states and their anodic oxidation in aqueous and non-aqueous solutions are discussed. The practical applications of electrochemistry in the isolation, refining, and determination of small amounts of the two elements are described. The bibliography includes 178 references.
TL;DR: In this article, the results of investigations of the physical and chemical properties of compounds of the noble gases and their structure, stability, and reactivity are given; the principal methods of synthesis are considered.
Abstract: The results of investigations of the physical and chemical properties of compounds of the noble gases and their structure, stability, and reactivity are given; the principal methods of synthesis are considered. Special attention is paid to the latest achievements in this field ? to investigations of complexes, derivatives of xenon fluorides and oxo-acids, xenon hexafluoride, and the study of the electronic structure. Non-empirical methods of calculation on the bonding in noble gas compounds are discussed and their results are compared with experimental results obtained with the aid of photoelectronic and X-ray electronic spectroscopy. Possible practical uses of the compounds of the noble gases are considered on the basis of the material presented. There is a bibliography of 400 references.
TL;DR: In this paper, a survey is made of experimental results on the equilibrium acidity of CH acids in the gas phase and in aqueous solution, as well as in dimethyl sulphoxide, cyclohexylamine, benzene, ether, and other aprotic solvents.
Abstract: A survey is made of experimental results on the equilibrium acidity of CH acids in the gas phase and in aqueous solution, as well as in dimethyl sulphoxide, cyclohexylamine, benzene, ether, and other aprotic solvents. Reasons are discussed for the sharp difference between CH and OH acids that appears on passing from the gas phase to aqueous solutions. Various acidity scales for CH acids in aprotic solvents — the McEwen, Streitwieser, Cram, Breslow, and polarographic scales, and the acidity scale in dimethyl sulphoxide — are compared. A list of 114 references is included.
TL;DR: The present state of the chemistry of myoinositol, a naturally occurring cyclitol, is discussed, with information on its stereochemistry, its physical and chemical properties, and the reactivity of the hydroxy-groups as mentioned in this paper.
Abstract: The present state of the chemistry of myoinositol, a naturally occurring cyclitol, is discussed, with information on its stereochemistry, its physical and chemical properties, and the reactivity of the hydroxy-groups. The principal methods of preparation of various derivatives, in which the cyclitol structure is unaffected, are considered. Special attention is paid to phosphoric esters of myoinositol, which are structural units of inositol phosphatides, a most important class of naturally occurring phospholipids. Specific properties of the phosphoric esters are examined, together with problems of their stability and synthesis. A list of 169 references is included.
TL;DR: Data on the methods for the formation of the aminoglycosidic linkage in the synthesis of alkyl and aryl am inoglycosides and oligosaccharides containing 2-amino-2-deoxyglycosyl residues are reviewed systematically.
Abstract: Data on the methods for the formation of the aminoglycosidic linkage in the synthesis of alkyl and aryl aminoglycosides and oligosaccharides containing 2-amino-2-deoxyglycosyl residues are reviewed systematically. The bibliography includes 229 references.
TL;DR: In this article, modern views on the kinetics and mechanism of the chemisorption of oxygen on group IB metals and their surface oxidation (up to the appearance of an oxide phase) are described.
Abstract: The modern views on the kinetics and mechanism of the chemisorption of oxygen on group IB metals and their surface oxidation (up to the appearance of an oxide phase) are described. Processes occurring in the temperature range from 0° to 300–400°C, which are of interest in connection with problems of catalysis and radioelectronics, are mainly considered. The bibliography includes 123 references.
TL;DR: A review of the most characteristic reactions of heteroaromatic cations and also tropylium and cyclopropenylium salts is given in this paper, where the properties of these cations are compared and classified in accordance with three types: 1. reactions involving recycling, 2. reactions of substituents in aromatic cations, 3. reactions with retention of the ring.
Abstract: The review gives a systematic account of the most characteristic reactions of heteroaromatic cations and also tropylium and cyclopropenylium salts. The properties of these cations are compared and classified in accordance with three types: 1. reactions involving recyclisation; 2. reactions of substituents in aromatic cations; 3. reactions with retention of the ring. Attention has been concentrated on the recyclisation reactions and studies which have not been described in previous reviews. The bibliography includes 220 references.
TL;DR: In this paper, the quantitative effect of the pentafluorophenyl ring on the reactivity of substituents (hydrogen, alkyl, aryl, carboxyl, amino, hydroxyl, and halogens) is surveyed.
Abstract: The quantitative effect of the pentafluorophenyl ring on the reactivity of substituents (hydrogen, alkyl, aryl, carboxyl, amino, hydroxyl, and halogens) is surveyed. The efficiency with which fluorine atoms at different positions in the benzene ring influence a reaction centre is discussed. An analysis of the σ-constants of the pentafluorophenyl group is also given. A list of 106 references is included.
TL;DR: In this paper, the silylation of pyrimidine and purine bases and the application of trimethylsilyl derivatives of nitrogen-containing heterocycles in the synthesis of nucleosides, nucleotides, and their analogues have been reviewed systematically.
Abstract: Data on the silylation of pyrimidine and purine bases and on the application of trimethylsilyl derivatives of nitrogen-containing heterocycles in the synthesis of nucleosides, nucleotides, and their analogues have been reviewed systematically. The bibliography includes 205 references.
TL;DR: In this article, a review of conformational analysis of six-membered heterocycles containing bivalent sulphur is presented, and the general conformation characteristics of the above class of compounds are reviewed.
Abstract: The review deals with one of the problems of dynamic stereochemistry — the conformational analysis of six-membered heterocycles containing bivalent sulphur. The general conformation characteristics of the above class of compounds are reviewed. The bibliography includes 115 references.
TL;DR: In this paper, the conditions governing the equilibrium in the reaction of fluoroapatite and mineral admixtures in natural phosphate raw materials with nitric acid and also certain problems of the kinetics of the decomposition of phosphate minerals are considered.
Abstract: The conditions governing the equilibrium in the reaction of fluoroapatite and mineral admixtures in natural phosphate raw materials with nitric acid and also certain problems of the kinetics of the decomposition of phosphate minerals are considered in the review. The principles of several technological schemes in the manufacture of Nitrophoska are described. The most important trends in new studies designed to obtain complex fertilizers by the decomposition of phosphates with nitric acid are also indicated. It is concluded that a promising method for the manufacture of Nitrophoska involves a procedure with cooling, retaining the main, fruitful idea of employing for the decomposition of phosphates nitric acid without the addition of other acids or their salts. The bibliography includes 96 references.
TL;DR: In this paper, the effect of molecular structure and the structure of substituents at the interaction functional groups and also of external factors on the relative stabilities of the isomers and on the nature of the equilibrium has been analyzed.
Abstract: The ring?chain isomeric (including tautomeric) transformations of hydroxy-, amino- and mercapto-derivatives of aldehydes, ketones, other carbonyl compounds, imines, hydrazones, and nitriles are examined. The effect of molecular structure and the structure of substituents at the interaction functional groups and also of external factors on the relative stabilities of the isomers and on the nature of the equilibrium has been analysed. The bibliography includes 246 references.
TL;DR: In this paper, a review deals with published work on the influence of chemical composition, degree of dispersion, and method of preparation on the specific activity of metallic catalysts, which is probably due to interaction between the catalyst surface and the surrounding medium, which converts the initial catalyst surface into a state which is relatively unaffected by variations introduced during the preparation of the catalyst.
Abstract: This review deals with published work on the influence of chemical composition, degree of dispersion, and method of preparation on the specific activity of metallic catalysts. In most cases the specific activity is determined by the nature of the metal, and is independent of the degree of dispersion or other parameters. This behaviour is probably due to interaction between the catalyst surface and the surrounding medium, which converts the initial catalyst surface into a state which is relatively unaffected by variations introduced during the preparation of the catalyst. 131 references.
TL;DR: In contrast to carbon, silicon does not tend to form multiple bonds as mentioned in this paper, and it was believed that compounds with multiple bonds at the silicon atom do not exist, but in recent years results were obtained which permitted a new approach to this interesting and important problem in the chemistry of organosilicon compounds.
Abstract: In contrast to carbon, silicon does not tend to form multiple bonds. Until recently it was believed that compounds with multiple bonds at the silicon atom do not exist, but in recent years results were obtained which permitted a new approach to this interesting and important problem in the chemistry of organosilicon compounds. The present review considers unsaturated compounds the compositions and properties of which may be described in terms of the hypothesis that the silicon atom forms (p–p)π double bonds. The bibliography includes 81 references.