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卷 94, 编号 11-12 (2024)
Articles
Synthesis of 4-{[(2Z)-4-Aryl-1-methoxy-1,4-dioxobut-2-en-2-yl]amino}benzoic acids and their reaction with ninhydrin
摘要
4-{[(2Z)-4-Aryl-1-methoxy-1,4-dioxobut-2-en-2-yl)]amino}benzoic acids were synthesized by reaction methyl esters of aroylpyruvic acids with 4-aminobenzoic (para-aminobenzoic) acid in a mixture of glacial acetic acid–ethanol, 1:1. The obtained compounds reacted with ninhydrin in glacial acetic acid to form 4-{3-aroyl-1ʹ,3ʹ-dihydro-1ʹ,3ʹ,5-trioxo-5H-spiro[furan-2,2ʹ-indan]-4-yl)amino}benzoic acids. The structure of the obtained compounds was determined using IR, NMR 1H and13C{1H} spectroscopy and X-ray crystallography.
1071-1079
Synthesis, structure, and analgesic activity of methyl (3R*,4S*)-4-aryl-2-oxo-1,2,3,4-tetrahydrobenzo[4,5]imidazo[1,2-a]pyrimidine-3-carboxylates
摘要
A series of new methyl (3R*,4S*)-4-aryl-2-oxo-1,2,3,4-tetrahydrobenzo[4,5]imidazo[1,2-a]pyrimidine-3-carboxylates was obtained by three-component condensation of dimethyl malonate, aromatic aldehyde, and 1H-benzimidazole-2-amine in methanol in the presence of piperidine. The structure of the obtained compounds was determined by 1H, 13C NMR spectroscopy and X-ray diffraction analysis. The analgesic activity of the synthesized compounds was studied.
1080-1085
Regioselective synthesis of new fused compounds based on pyridine-2-chalcogenyl halides, 1-alkenes and arylalkenes
摘要
Regioselective synthesis of new fused compounds in high yields was developed based on reactions of pyridine-2-chalcogenyl halides with alkenes and arylalkenes. The reaction of pyridine-2-chalcogenyl halides with simple 1-alkenes leads to 2-alkyl-2,3-dihydro[1,3]chalcogenazolo[3,2-a]pyridin-4-ium halides, while reactions with arylalkenes proceed with the opposite regio direction with the formation of 3-aryl substituted derivatives.
1086-1094
Extraction of lanthanides(III) with of bis[N-octyl-N-(2-diphenylphosphinylethyl)]amide of diglycolic acid from nitric acid solutions
摘要
Extraction of microquantities of lanthanides(III) from HNO3 solutions with solutions of bis[N-octyl-N-(2-diphenylphosphinylethyl)]amide of diglycolic acid [Ph2P(O)CH2CH2N(Oct)C(O)CH2]2O in organic solvents was studied. Stoichiometry of extracted complexes was determined, influence of extractant structure, nature of organic diluent and composition of aqueous phase on efficiency and selectivity of extraction of lanthanide(III) ions into organic phase was considered. It was shown that modification of diglycolamides by introduction of additional coordinating groups CH2CH2P(O)Ph2 into their molecule via amide nitrogen atom leads to increase of extraction of lanthanides(III) from neutral and weakly acidic nitrate media when using a mixture of n-dodecane with tributylphosphate as a solvent.
1095-1101
Thermolysis of a mixture of tetramminepalladochloride and ammonium heptamolybdate in an inert atmosphere
摘要
The results of thermolysis of a mixture of [Pd(NH3)4]Cl2 and (NH4)6Mo7O24·4H2O are presented. Thermogravimetry, differential scanning calorimetry and mass spectrometry in an inert atmosphere (Ar) in the temperature range of 50–550°C were used to establish the ranges of formation of intermediate products of the mixture interaction and to identify them. The intermediate and final products of thermolysis were identified by X-ray phase analysis. The latter is represented by two phases: a solid solution Pd1–xMox and MoO3. It was shown that the presence of the [Pd(NH3)4]2+ ion in the mixture induces the reduction of Mo7O246– ions. Ammonia in statu nascendi and palladium are the reducing agents. The formation of the solid solution occurs through the formation of metallic phases – palladium and molybdenum.
1102-1111
Stability of cadmium(II) complexes with glycinate ion in dimethyl sulfoxide aqueous solutions
摘要
The stability constants of cadmium(II) complexes with glycine anion in aqueous dimethyl sulfoxide solutions were determined by potentiometric titration at a temperature of 298 K and an ionic strength of 0.1 M solutions at sodium perchlorate background. When the concentration of dimethyl sulfoxide in the solution increases, an increase in the stability of cadmium(II) glycinates is observed. The obtained data are compared with the literature values of stability constants in aqueous solutions of dimethylsudium oxide glycinate complexes with d-metal ions, as well as cadmium(II) complexes with N,O-donor ligands. The Gibbs energies of the cadmium(II) glycinate complex transfer from water to aqueous dimethyl sulfoxide were calculated using the literature data. The contribution of the reactants' resolvation to the Gibbs energy change of the complex formation was considered. We concluded that the increased stability of cadmium(II) glycinate in aqueous solutions of dimethyl sulfoxide is mainly due to a weakening of the solvate state of the ligand.
1112-1120
LaFeO3 nanofibers as materials for gas sensors
摘要
LaFeO3 nanofibers were prepared by electrospinning from polymer precursor-filled solutions and characterized by X-ray diffraction, scanning electron microscopy, low-temperature nitrogen adsorption, infrared spectroscopy, and X-ray photoelectron spectroscopy. The gas-sensing properties of the materials were studied in detecting CO, NH3, acetone and methanol. The synthesized LaFeO3 fibers exhibit a high sensory response to volatile organic compounds.
1121-1132