Том 88, № 5 (2018)
- Жылы: 2018
- Мақалалар: 39
- URL: https://journals.rcsi.science/1070-3632/issue/view/13697
Article
Special Features of Oxidation of Hafnium Diboride Nanoparticles of Different Dispersity
Аннотация
Products of oxidation of HfB2 particles with mean size 50–55 and 20–25 nm with air oxygen under polythermal and isothermal conditions have been studied by means of thermal analysis, scanning electron microscopy, X-ray energy-dispersive analysis, and elemental analysis. Rate constants of oxidation of the HfB2 nanoparticles have been determined.
The Role of Hydrogen Bond in the Mechanism of Autocatalytic Reaction between Acetic Anhydride and tert-Butyl Hydroperoxide
Аннотация
The role of hydrogen bonding in the autocatalytic reaction of acetic anhydride with tert-butyl hydroperoxide in CC14 has been elucidated. The stage-by-stage mechanisms of formation of hydrogen-bonded complexes. Structure and energy parameters of stable conformers of the compounds and energy of the major and transition states have been determined by means of B3LYP/aug-cc-pVDZ and B3LYP/aug-cc-pVTZ methods. The contribution of the O···HO hydrogen bonds in the stabilization of the complexes has been determined using the noncovalent interactions index. 1-Hydroxy-1-alkylperoxy compound is the most stable intermediate.
Inductive Hydroxyhalogenation of Bicyclo[2.2.1]heptenes and Synthesis of Amino Alcohols from the Reaction Products
Аннотация
A method of synthesis of aminobicycloheptanols by the hydroxyhalogenation of bicyclo[2.2.1]- heptene and its alkyl derivatives in a cycloolefin‒oxidant‒hydrogen halide system to induce electrophilic intermediates followed by substitution of the halogen atoms by amino groups of different compositions and structures. It was found that the selectivity of the reaction depends on the formation/consumption rate ratio for the electrophilic intermediate. A high selectivity with respect to hydroxyhalides takes place, when the consumption rate of the latter intermediate is higher than its formation rate. An increase in the pH of the medium becomes higher than 10.5 decreases the yield of amino alcohols and changes the reaction direction due to acceleration of dehydrohalogenation and formation of the corresponding epoxides.
Halogenation of Diamantane by Halomethanes Under the Action of Zeolites
Аннотация
Catalytic chlorination and bromination of diamantane with halomethanes was performed under the action of zeolites NaY-mmm, HY-mmm, and FeHY-mmm. Optimal ratios of the catalyst, reagents and conditions for selective synthesis of chloro- and bromo-substituted diamantanes were found.
Influence of Oxidation Conditions on the Yield of 2-Substituted Imidazole-4,5-dicarboxylic Acids
Аннотация
Conditions were found which allow 2-alkyl-substituted imidazole-4,5-dicarboxylic acids to be synthesized in preparative quantities by the oxidation of 2-alkylbenzimidazoles with hydrogen peroxide. It was shown that optimal results can be obtained at the concentration of 2-alkylimidazole in sulfuric acid of 1 M and the hydrogen peroxide: 2-alkylbenzimidazole molar ratio of 11: 1. Oxidation under these conditions results in higher yields of the target 2-alkylimidazole-4,5-dicarboxylic acids, including those with a branched alkyl group.
Anion-Radical Salts of 7,7,8,8-Tetracyanoquinodimethane with Cations in the Basis of Alkylolpyridines
Аннотация
Anion-radical salts of 7,7,8,8-tetracyanoquinodimethane with cations on the basis of methylol- and ethylolpyridines, N-methyl- and N-ethyl alkylolpyridines, were synthesized. Their composition is determined by the method of electronic spectroscopy, and the thermal stability is studied. The nature of the salts is investigated by the method of IR spectroscopy: it is shown that the conducting properties depend both on the nature of the alkyl group and on the position of the alkylol substituent. The presence of hydroxy groups in the conducting anion-radical salts allow their application as electronic organic materials for the design of conducting film coatings.
Synthesis and Structure of Cyclohexenes Functionalized by Nitro and Trifluoro(chloro)methyl Groups
Аннотация
Cyclohexenes functionalized by nitro and trihalomethyl groups were produced by condensation of 1-nitro- and 1-bromo-1-nitro-3,3,3-trifluoro(chloro)propenes with 2-methyl- and 2,3-dimethyl-1,3-butadienes; their structure was characterized by IR, 1H, 13C, 19F NMR spectroscopy, and X-ray diffraction method.
Single-Pot Synthesis of Alkyl-Substituted Quinolines and Indoles via Photoinduced Oxidation of Primary Alcohols
Аннотация
Single-pot synthesis of alkyl-substituted quinolines and indoles has been performed via photoinduced oxidation of primary aliphatic alcohols (C2–C5) and condensation of the aldehydes (products of the alcohols oxidation) with aniline under the action of iron-containing catalysts and inorganic oxidants. The synthesis was the most efficient in the presence of FeCl3·6H2O as catalyst and 10% aqueous solution of NaOCl as oxidant with irradiation by Hg lamp. The synthesis mechanism through photoinduced oxidation of primary aliphatic alcohol has been suggested.
5-Amino-Substituted Derivatives of 4-Nitrofurazane: Synthesis, Structure, and Biological Activity
Аннотация
New amination reactions of 5-chloro-4-nitrobenzofurazane with different amines were studied. The reactions of 5-chloro-4-nitrobenzofurazane with 2,4,6-trichloro-, para-acetyl-, and para-carboxyethylanilines gave the products of aromatic nucleophilic substitution of the chlorine substituent in the nitrogenous heterocycle, the composition and structure of which was established by chemical, physical, and physicochemical methods and X-ray diffraction analysis. The thermal stability was studied by synchronous thermogravimetry and differential scanning calorimetry (TG‒DSC). The synthesized compounds showed a high antibacterial and antimycotic activity against human and animal pathogenic microflora.
Synthesis and Structure of 3-Aryl-2,4-dibenzoyl-5-hydroxy-5-methylcyclohexanones and 2-Benzoyl-5-hydroxy-5-methyl-3-phenylcyclohexanone
Аннотация
The reaction of benzoylacetone with aromatic aldehydes under basic catalysis conditions afforded 3-aryl-2,4-dibenzoyl-5-hydroxy-5-methylcyclohexanones. The reaction of benzoylacetone with benzalacetone led to the formation of 2-benzoyl-5-hydroxy-5-methyl-3-phenylcyclohexanone.
Synthesis of 5-Aryl-4-aroyl-3-hydroxy-1-cyanomethyl-3-pyrrolin-2-ones
Аннотация
5-Aryl-4-aroyl-3-hydroxy-1-cyanomethyl-3-pyrrolin-2-ones were synthesized by a three-component reaction of methyl aroylpyruvate with a mixture of aromatic aldehyde and 2-aminoacetonitrile sulfate in glacial acetic acid in the presence of anhydrous sodium acetate.
Three-Component Reaction of 4-Methylpyridine with Alkyl Propiolates and Secondary Phosphine Chalcogenides
Аннотация
The reaction between 4-methylpyridine, alkyl propiolates, and secondary phosphine oxides proceeded as N-vinylation-C-phosphorylation with stereo- and regioselective formation of (E)-N-ethenyl-C2- phosphoryl-1,2-dihydropyridines [when using bis(2-phenylethyl)phosphine oxide] or (E)-N-ethenyl-C4- phosphoryl-1,4-dihydropyridines (when using diphenylphosphine oxide). The process occurred at 60–62°C within 3 h to give functional dihydropyridines in 40–82% yield. Under similar conditions, bis(2-phenylethyl) phosphine sulfide and selenide reacted with alkyl propiolates preferably by nucleophilic PH-monoaddition at the triple bond.
Generation of tert-Butyl-λ5-phosphanedione and Its Chemical Properties
Аннотация
Flash vacuum thermolysis of trimethylsilyl tert-butylphosphonohalidates involved elimination of halo(trimethyl)silane with the formation of tert-butyl-λ5-phosphanedione whose structure was confirmed by chemical reactions. tert-Butyl-λ5-phosphanedione readily undergoes trimerization, reacts with 2-phenyloxirane to give cycloaddition product, and takes up alcohols.
Recognition of R- and S-Isomers of α-Alanine by Chiral Nanotubes
Аннотация
DFT PBE/3ζ study of relative stability of the R- and S-isomers of α-alanine in open carbon nanotubes with chirality indices (5,5), P,M-(5,1) and P,M-(5,2) has shown that the encapsulated molecule of the amino acid notably changes its geometrical and electronic characteristics. Besides, for the clusters α-alanine@nano (5,2) the most stable are practically degenerate in energy adducts S-alanine@P-(5,2) and R-alanine@М-(5,2). All this indicates the ability of chiral nanotubes to recognize encapsulated molecules of the R- and S-isomers.
Analysis of Hydrogen Bonding Network in the Systems Containing Chloride-Based Ionic Liquids with Cellulose/Cellobiose by Fourier-Transform Infrared Spectroscopy
Аннотация
Hydrogen bonds formed upon dissolution of cellulose and cellobiose in ionic liquids, 1-butyl-3- methylpyridinium and 1-butyl-3-methylimidazolium chlorides, have been analyzed and characterized by means of Fourier-transform infrared spectroscopy and quantum-chemical calculation. The obtained data have been used for assignment of absorption bands of individual OH groups and determination of hydrogen bonds energy in the solutions.
Preparation of a Polymer via Condensation of o-Phenylenediamine with p-Xylylene Dibromide and Its Properties
Аннотация
Condensation of para-dibromoxylene and ortho-phenylenediamine in glass ampule at 150°С in an alkaline aqueous solution has yielded polymer with completely substituted N–H hydrogen atoms, capable of formation of polymeric cation-radicals. Complexes of this polymer and N,N,N',N'-tetrabenzyl-o-phenylenediamine with Co(II), Ni(II), Cu(II), and Ag(I) have been obtained, and their structure has been studied.
Redox Isomerism of α-Ferrocenylcarbenium Ions
Аннотация
The formation of α-ferrocenylcarbenium ions FcC+H2 (λmax 600 nm) and FcC+HCH3 (λmax 730 nm) and their redox isomerism at the protonation of ferrocenylmethanol and vinylferrocene was proved using the method of electronic spectroscopy. The effect on the process of the solvent and acid nature as well as of hydrogen peroxide additives is discussed.
Thermodynamics of Complex Formation of Ce3+ and La3+ Ions with Glycylglycine in Aqueous Solution
Аннотация
Enthalpy of the complex formation between diglycine (HL±) and Ce3+ or La3+ at 308.15 K and ionic strength of 0.5 mol/L (KNO3) has been determined by means of calorimetry. Thermodynamic parameters of the diglycine complexes formation with Ce3+ and La3+ at different metal to ligand molar ratios have been determined.
Comparative Study of Redox Reactions of Aqua- and Thiocyanatocobalamin
Аннотация
The interaction of aqua- and thiocyanatocobalamin with sodium hydroxymethanesulfinate in neutral aqueous solution has been studied, and the kinetic as well as activation parameters of the reactions have been determined. The reduction of the aqua complex is faster in comparison with the thiocyanato one. In contrast to the earlier studied reaction of hydroxymethanesulfinate with cyanocobalamin, reduction of aquaand thiocycnatocobalamins occurs via the associative mechanism.
New Acylhydrazones of Indole Series and Their Metal Complexes
Аннотация
By the reaction of 2-chloroindole-3-carbaldehyde with acylhydrazones new acylhydrazones of the indole series have been synthesized, and their structure, the possibility of cyclization to pyrazoloindoles, and complexing properties have been studied. By means of quantum chemical DFT calculations taking into account the solvent effect it was shown that the reaction of 2-chloroindole-3-carbaldehyde and the corresponding acylhydrazine is an exothermic process, irrespective of which final product is formed, indolemethylenehydrazide or pyrazoloindole. Therefore, both possible transformations in the studied reacting system are controlled kinetically and not thermodynamically.
Synthesis and Complex Formation of Rhodamine-Substituted Spirobenzopyranindolines
Аннотация
Novel spirobenzopyranindolines containing a rhodamine fragment linked to a benzopyran fragment with an aminomethylene spacer were synthesized by the reaction of 7-hydroxy-6-formyl-substituted spiropyrans and rhodamine B hydrazide. The synthesized spiropyrans in toluene and acetone are present in the spiropyran‒spirolactam form. The 5-methyl-substituted was the only to exhibit photochromism. Adding Zn(II), Ni(II), Co(II), and Cd(II) perchlorates to the spiropyran solutions leads to intense coloration due to complex formation.
Investigation of Kinetics of Coordination of meso-Nitro-Substituted Derivatives of 5-Phenyl-β-octaalkylporphine with Palladium Acetate
Аннотация
Kinetics of the formation reactions of palladium complexes of meso-nitro-substituted 5-phenyl-β- octaalkylporphine derivatives in the Pd(OAc)2–acetonitrile system at 303–323 K was studied by spectrophotometry. The kinetic parameters of the formation reaction of complexes of porphyrins under study with palladium and zinc previously prepared, as well as their corresponding fluorescence spectra, were subjected to a comparative analysis. The parameters of electron absorption spectra of all palladium porphyrinates obtained were determined.
Synthesis and Properties of Zinc(II), Cadmium(II), Manganese(III), and Tin(IV) Octakis(4-methoxyphenyl)porphyrins
Аннотация
Coordination of octakis(4-methoxyphenyl)porphyrin with d-metal salts and metal exchange reactions of its cadmium complex were studied by spectrophotometry in dimethylformamide. Zinc(II), cadmium(II), manganese(III), and tin(IV) octakis(4-methoxyphenyl)porphyrins were isolated and identified. Spectrophotometric titration of zinc(II) octakis(4-methoxyphenyl)porphyrin with 1,4-diazabicyclo[2.2.2]octane afforded the corresponding 1: 1 complex with axial coordination of the extra ligand.
Electroluminescent Iridium-Containing Functionalized Polynorbornenes Emitting Red Light
Аннотация
A new iridium(III) cyclometalated complex NBEpzIr(Tiq)2 {NBEpzH is 4-[(bicyclo[2.2.1]hept-5- en-2-yl)hydroxymethylidene]-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazole-3-on and TiqH is 1-(thien-2-yl)isoquinoline} was synthesized. Copolymers with carbazole and iridium-containing fragments in side chains were obtained on the basis of the synthesized monomer by the method of ring-opening metathesis polymerization. The copolymers exhibit intense photoluminescence and electroluminescence of deep red color.
Special Features of Localization of Eu3+ Ion in the Matrix of (GdxY1–x)2O3: Eu3+ Solutions During Sol-Gel Synthesis of the Luminophor
Аннотация
Sol-gel synthesis of the (GdxY1–x)2O3: Eu3+ solid solutions (3.5 mol %) allows for the increase in the energy efficiency of emission of the red luminophor. The study of distribution of the luminescence activator Eu3+ has revealed that these ions substitute the Gd3+ ones in the cationic sublattice of ternary solid solution. The Eu3+ ions are predominantly localized in the noncentrosymmetrical position C2 at x < 0.50 and in centrosymmetrical position C3i at x > 0.50. The increase in the Eu3+ ions concentration in the C3i position stabilizes the cubic high-temperature structure of the solid solution in comparison with the monoclinic phase. The solid solution with x = 0.75 has been found to be the most efficient luminophor.
Mixed Ligand Complexes Derived from Semicarbazone Schiff Base and Heterocyclic Ligands: Structure and Antimicrobial Activity
Аннотация
A series of M(II) ternary complexes [M(L)Phen] and [M(L)Oxine], where M = Co(II), Ni(II), Cu(II), and Zn(II), L = ((2-hydroxynaphthalen-1-yl)methylene)-4-nitrobenzohydrazide, Phen = 1,10-phenanthroline and Oxine = 8-hydroxy chloroquinoline, were synthesized and characterized by UV-Vis, ESR, IR, mass spectra, and TG-DTA data. Morphology and crystallinity of the complex [Ni(L)Phen] were studied by scanning electron microscopy. The crystal systems of Cu(II) complexes were determined by powder X-ray diffraction. Biological activity of the ligand and its metal complexes has been screened against four bacterial strains.
Ionic Liquid [BDBDMIm](Br3)2 As a New Efficient Brominating Agent in the Synthesis of γ-Butyrolactones
Аннотация
γ-Butyrolactones can be synthesized by a solvent free multicomponent reaction of aldehydes with ethylpyruvate followed by an intramolecular cyclization using the new brominating agent, ionic liquid [BDBDMIm](Br3)2. This is the first synthesis of γ-butyrolactones starting with aldehydes via the Knovenagel condensation and halogenation, followed by multicomponent cyclization reaction. The present method offers several advantages such as solvent free mild conditions, simple procedure, excellent yields, and environmental friendliness. All synthesized compounds were characterized by their IR, 1H and 13C NMR spectra.
Microwave-Assisted Synthesis of Novel Spirochromanone–Aurone Hybrids and Their Antimicrobial Activity
Аннотация
New chromanone and aurone hybrids have been synthesized by conventional and microwave induced methods from substituted (E)-7-hydroxy-6-[3-(p-tolyl)acryloyl]spiro[chroman-2,1'-cyclohexan]-4-one with high yields. Structures of the synthesized compounds have been elucidated from IR, 1H and 13C NMR, and mass spectra. All newly synthesized compounds were tested in vitro for their antimicrobial activity. Methoxysubstituted spirochromanones revealed the best antimicrobial profile.
Synthesis and Anticancer Evaluation of 1,2,4-Oxadiazole Linked Imidazothiadiazole Derivatives
Аннотация
A series of 1,2,4-oxadiazole linked imidazothiadiazole derivatives 11a–11j have been synthesized. All derivatives were evaluated for anticancer activity against three human cancer cell lines (A375, MCF-7, and ACHN) and demonstrated activity comparable with that of doxorubicin. Three compounds 11b, 11c, and 11j exhibited higher anticancer activity than the positive control. The range of IC50 for the compounds 11b, 11c, and 11j is determined to be from 0.11 to 2.98 μM.
6-Substituted 1,4-Naphthoquinone Oxime Derivatives (III): Synthesis and Cytotoxic Evaluation
Аннотация
As a continuous study, a set of 23 new 6-substituted 1,4-naphthoquinone oxime derivatives are synthesized and screened for their in vitro cytotoxic activity. Four of those oxime derivatives demonstrate more potent cytotoxic activity towards K562, HCT-15, and HCT-116 cell lines than a reference drug 5-Fu. In particular, compound 21g exhibits the strongest inhibitory activity against K562 cell lines with IC50 values of 1.25 μM. According to flow cytometry data, compound 21g can arrest cell cycle at S phase and induce a strong apoptotic response in K562 cells. The preliminary structure-activity relationship study shows that the nature of substituents in positions 6 and 1' of 1,4-naphthoquinone derivatives significantly affect their cytotoxic activity.
An Efficient One-Pot Synthesis and Anticancer Activity of 4'-Substituted Flavonoids
Аннотация
A number of 4'-substituted (R = H, Me, Cl, F) flavone derivatives is synthesized from 2-hydroxyacetophenones using the modified Baker–Venkataraman reaction. Compound [3-(4-fluorobenzoyl)-5- hydroxy-4'-fluoroflavone] was synthesized for the first time with the yield of 12%. Antiproliferative assays indicate that the synthesized flavones with F substituent at the 4' position demonstrate higher activity than the other flavone derivatives, particularly against HeLa and MCF-7 with the IC50 9.5 and 2.7 μM, respectively.
Letters to the Editor
Synthesis and Properties of 3-Alkyl-1-methoxycarbonylmethyl- 5-dialkylaminomethylpyrazolines and Their Functional Derivatives
Аннотация
3-Alkyl-1-methoxycarbonylmethyl-5-dialkylaminomethylpyrazolines have been synthesized by the reaction of 3-alkyl-5-dialkylaminomethylpyrazolines with methyl monochloroacetate. The reaction of the synthesized compounds with hydrazine hydrate and KOH afforded new functional derivatives of 3-alkyl-5- dialkylaminomethylpyrazolines. The biological activity of the synthesized functional derivatives of pyrazolines was investigated.
Phosphorus-Containing Aminocarboxylic Acids: XV. α,ω-Diamino-ω,ω-diphosphonoalkylcarboxylic Acids
Аннотация
A general method for the synthesis of phosphonic aminocarboxylic acids combining aminodiphosphonic and amino acid functions in one molecule was developed. Amino acids of a new type are AP-acids analogs, which are ligands of glutamate receptors that determine the processes of information transmission and processing in the central nervous system, and can also be promising compounds as new components of radiopharmaceuticals.
Reactions of Tricymantrenylantimony with Halogens. Synthesis and Structure of Tricymantrenylantimony Dihydroxide
Аннотация
Tricymantrenylantimony dibromide [C5H4Mn(CO)3]3SbBr2 and dichloride [C5H4Mn(CO)3]3SbCl2 were synthesized by the reaction of tricymantrenylantimony with bromine and chlorine in chloroform; the products are transformed into tricymantrenylantimony dihydroxide [C5H4Mn(CO)3]3Sb(OH)2 by the action of potassium hydroxide in ethanol. Antimony atoms in the dihydroxide have a distorted trigonal–pyramidal coordination with oxygen atoms in axial positions [OSbO 175.66(8)°; Sb–O 1.987(2), 2.049(2), Sb–C 2.086(2), 2.101(2), and 2.105(2) Å].
Palladium(II) Polynuclear Complex with β-Mercaptoethanol
Аннотация
A hexanuclear palladium complex with β-mercaptoethanol was synthesized and characterized by various physical methods. A single sulfur atom participates in the coordination and binds two palladium atoms. The hydroxyl group of the ligand is not involved in the complex formation. A crown-shaped hexanuclear cycle without a metal-metal bond is formed.
Methods for Improving Photocatalytic Activity of Zinc Sulfide
Аннотация
Results of studying zinc sulfide catalytic activity in the reaction of methylene blue photodegradation are presented. It was found that the process rate increases when the catalyst is doped with titanium(IV) oxide. The rate depends on the ratio of anatase/rutile crystal phases.
Retraction Note
Retraction Note to: “Potassium fluoride-barium oxide catalysis in an easy and efficient synthesis of methysticin from piperonal under microwave irradiation”
Аннотация
The article published in volume 85, no. 8, pp. 1939–1944, DOI: 10.1134/S107036321508023X has been retracted by the Editor-in-Chief. After careful investigation it was found that experimental data made by a laboratory not cited as a reference were taken over by error. The experimental data was taken from Liang Liao, Doctoral Thesis, Laboratory of Molecular Chemistry and Thio-Organic Caen-France, 1999. (https://doi.org/www.theses.fr/1999CAEN2021). All authors are informed on the retraction and agree with it.
Retraction Note to: “Easy and green synthesis of 6-(arylvinyl)-4-hydroxy-3-(phenylsulfanyl)-2H-pyran-2-ones in aqueous potassium hydroxide”
Аннотация
The article published in volume 86, no. 12, pp. 2881–2886, DOI: 10.1134/S1070363216120550 has been retracted by the Editor-in-Chief. After careful investigation it was found that experimental data made by a laboratory not cited as a reference were taken over by error. The experimental data was taken from Liang Liao, Doctoral Thesis, Laboratory of Molecular Chemistry and Thio-Organic Caen-France, 1999. (https://doi.org/www.theses.fr/1999CAEN2021). All authors are informed on the retraction and agree with it.