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Sigmatropic Rearrangement-Based Synthesis of 4-Alkenyl-1,3-dithiol-2-ones
Organic Letters. 2019. Vol. 21. No. 10. P. 3726-3729.
Ostrovskis P., Mikhaylov Andrey A., Zard S.
A series of conjugated 4-alkenyl-1,3-dithiol-2-ones have been prepared by microwave-assisted rearrangement of S-(4-acyloxy-2-alkynyl)-O-ethyl xanthates in moderate to good yields. The synthetic approach is based on a combination of [3,3] and [1,5] sigmatropic rearrangements as well as the intermediacy of a reactive betaine that induces the ionic elimination of the acyloxy group. The [1,5] sigmatropic rearrangement was confirmed by a deuterium-labeling experiment.
Ikonnikova V., Zhigileva E., Al Mufti A. et al., Journal of Organic Chemistry 2023 Vol. 88 No. 14 P. 9737-9749
Added: August 18, 2023
Chaplygin D., Ananyev I., Fershtat L. et al., Synthesis 2020 Vol. 52 No. 18 P. 2667-2678
A novel method for the synthesis of a diverse series of functionally substituted five-membered heterocyclic compounds via atom-economic, regio-, and diastereoselective one-pot reaction cascade was developed. This approach involves a ring opening in 4-arylfuroxans to alpha-oximinoarylacetonitrile oxides followed by [3+2] cycloaddition to various dipolarophiles to afford multisubstituted isoxazoles and isoxazolines. Subsequent azole-azole rearrangement of (oximino)isoxazolines/-isoxazoles, ...
Added: April 12, 2021
Zaitseva E., Smirnov A., Myasnyanko I. et al., New Journal of Chemistry 2021 Vol. 45 No. 4 P. 1805-1808
2-Dialkylamino-arylidene-imidazolones undergo intermolecular tandem [1,5]-hydride shift and cyclization to form spirocyclic tetrahydroquinoline derivatives under TiCl4 promotion. Different substitutions on each of the aryl, amino and imidazole fragments are tolerated, which results in 20+ examples and 25–95% yields. ...
Added: February 2, 2021
Izmest’ev A., Karnoukhova V., Larin A. A. et al., International Journal of Molecular Sciences 2022 Vol. 23 No. 22 Article 13820
Methods for the synthesis of two types of isomeric dispirocompounds based on imidazothiazolotriazine and pyrrolidineoxindole, differing in the structure of imidazothiazolotriazine fragment, namely, linear dispiro[imidazo[4,5-e]thiazolo[3,2-b][1,2,4]triazine-6,3′-pyrrolidine- 4′,3″-indolines] and angular dispiro[imidazo[4,5-e]thiazolo[2,3-c][1,2,4]triazine-7,3′-pyrrolidine-4′,3″-indolines] were proposed. The first method relies on a 1,3-dipolar cycloaddition of azomethine ylides generated in situ from paraformaldehyde and N-alkylglycine derivatives to the corresponding oxindolylidene derivatives ...
Added: January 20, 2023
Андрюшечкин Б. В., Eltsov K., Pavlova T. et al., Journal of Chemical Physics 2018 Vol. 148 No. 24 Article 244702
The adsorption of O-2 on Ag(111) between 300 and 500 K has been studied with temperature-programmed desorption (TPD) and scanning tunneling microscopy (STM). At the first stage of adsorption, the disordered local oxide phase (commonly looking in STM as an array of black spots) is formed on the surface irrespective of the substrate temperature. The maximum concentration of black spots was found to be approximate to 0.11 ML, which corresponds to an oxygen coverage of approximate to 0.66 ML. Taking into account that the nucleation of the Ag(111)-p(4 x 4)-O phase starts after the saturation of the disordered phase, one ...
Added: October 25, 2021
Nikolaev S. A., Tsodikov M. V., A. V. Chistyakov et al., Catalysis Today 2021 Vol. 379 P. 50-61
PdCu/Al2O3 (Pd = 0.1 wt.%, Cu = 0.1 wt.%) catalyst and its monometallic analogues (Pd/Al2O3 and Cu/Al2O3) were prepared by combination of deposition-precipitation and impregnation methods. The structure of the catalysts was studied by means of XRD, TEM, EDS, TPD-NH3, and DRIFTS. In a standard run (275 ○C, 5 h), Cu/Al2O3 converts 11 % of ethanol to α-alcohols with ...
Added: November 11, 2023
I. V. Sedov, Arutyunov V. S., Tsvetkov M. V. et al., Eurasian Chemico-Technological Journal 2022 Vol. 24 No. 2 P. 157-163
The possibility of using coalbed methane to produce methanol is assessed. Methanol can be obtained from methane both by direct partial oxidation and from synthesis gas formed through the oxidative conversion of methane. Thermodynamic analysis of coalbed methane conversion was carried out to determine the conditions for obtaining synthesis gas with the ratio [H2 ]/[CO] = ...
Added: October 7, 2022
Lototskyy M., Davids M. W., Sekgobela T. K. et al., Inorganics 2023 Vol. 11 No. 8 Article 319
Hydrolysis of light metals and hydrides can potentially be used for the generation of hydrogen on-board fuel cell vehicles, or, alternatively, for refilling their fuel tanks with H2 generated and pressurised without compressor on site, at near-ambient conditions. Implementation of this approach requires solution of several problems, including the possibility of controlling H2 release and ...
Added: August 11, 2023
Yurova P., Караванова Ю. А., Yaroslavtsev A. B., Журнал неорганической химии 2015 Т. 60 № 11 С. 1551-1553
The properties of hybrid materials based on the MK-40 heterogeneous membrane, the MF-4SK homogeneous membrane, and zirconium oxide with a functionalized surface are studied. The ionic conductivity and diffusion parameters of these materials were studied. The presence of the asymmetry effect of diffusion permeability and mutual diffusion of HCl and NaCl solutions through the studied ...
Added: November 13, 2019
Trifonova E., Ankudinov N., Mikhaylov A. A. et al., Angewandte Chemie - International Edition 2018 Vol. 57 No. 26 P. 7714-7718
The rapid development of enantioselective C−H activation reactions has created a demand for new types of catalysts. Herein, we report the synthesis of a novel planar‐chiral rhodium catalyst [(C5H2tBu2CH2tBu)RhI2]2 in two steps from commercially available [(cod)RhCl]2 and tert‐butylacetylene. Pure enantiomers of the catalyst were obtained through separation of its diastereomeric adducts with natural (S)‐proline. The catalyst promoted enantioselective ...
Added: September 29, 2020
Shirokova V., Ikonnikova V., Solyev P. et al., Synthesis 2021 Vol. 53 No. 24 P. 4689-4699
Directly accessible 8-substituted tetrahydroquinolines undergo 1,5-hydride shift-triggered cyclization to provide hardly accessible julolidine derivatives in 20-98% yield under scandium (III) triflate catalysis. The scope of the reaction, several follow-up transformations and a remarkable side-process discovered during the conditions optimization are highlighted. ...
Added: July 29, 2021
Svitanko I., Pivina T. S., Khakimov D. V., Journal of Molecular Modeling 2024 Vol. 30 Article 93
Using quantum chemistry and atom–atom potential methods, the molecular and crystal structures of cubane 1 and all types of unsubstituted azacubanes 2–22 were calculated. Alternative possible polymorphs of cubane 1 have been proposed. The thermochemical properties of azacubanes in the gas and solid phases were assessed. Thermodynamic aspects of stability are considered, and a significant ...
Added: March 13, 2024
Astakhov A., Chernenko A., Kutyrev V. et al., Inorganic Chemistry Frontiers 2023 Vol. 10 No. 1 P. 218-239
C-Amino-1,2,4-triazoles are challenging polynitrogen substrates for metal-catalyzed arylation due to their multidentate character, enhanced coordinating ability and decreased nucleophilicity of the amino group. In the present study, the Buchwald–Hartwig cross-coupling of diverse 3(5)-amino-1,2,4-triazoles with aryl chlorides and bromides delivering (hetero)arylamino-1,2,4-triazoles in good-to-excellent yields under Pd/NHC catalysis was developed. The use of Pd complexes with bulky ...
Added: February 14, 2024
Faraonov M., Romanenko N., Mikhailenko M. et al., New Journal of Chemistry 2021 Vol. 45 P. 13599-13607
Reduction of organic dye trans-perinone (its abbreviation is perinone) in different experimental conditions allows us to obtain and characterize radical anion {cryptand(K+)}[perinone˙−] (1) and dianion {PPN+}2[perinone2−]·2C6H4Cl2 (2) salts of this dye. The salts have layered structures. Perinone˙− radical anions form π–π stacked dimers in 1 with an effective interaction between them, whereas perinone2− dianions are ...
Added: October 21, 2022
Maslov V., Теоретическая и математическая физика 2019 Т. 201 № 1 С. 65-83
We study the process of a nucleon separating from an atomic nucleus from the mathematical standpoint
using experimental values of the binding energy for the nucleus of the given substance. A nucleon becomes
a boson at the instant of separating from a fermionic nucleus. We study the further transformations of
boson and fermion states of separation in a ...
Added: November 1, 2019
Medvedev M., Belyy A., Levina A. et al., European Journal of Organic Chemistry 2019 Vol. 2019 No. 26 P. 4133-4138
The reaction of di(methoxycarbonyl)tetrazine with substituted cycloprop-2-ene-1-carboxylates gives a series of 3,4-diazanorcaradienes and 1,2-diazepines. The influence of the nature of cyclopropenes and the reaction conditions on its selectivity was investigated. The addition of nucleophiles to norcaradienes was studied and a rare example of the “walk” rearrangement in this class of compounds was revealed. ...
Added: October 12, 2019
Kotov V., Laurinavichyute V., Kazyrevič A., ChemTexts 2022 Vol. 8 No. 4 Article 21
In the 1920s, due to the First World War and subsequent events in the Soviet Union, many educated and ambitious young people of diferent nationalities were forced to leave the country where they were born. A lot of them ended up in Prague. Thanks to the policy of President Masaryk, students who did not complete their education ...
Added: November 28, 2022
Panina I., Balandin S., Tsarev A. et al., International Journal of Molecular Sciences 2023 Vol. 24 No. 2 P. 1
To date, a number of lantibiotics have been shown to use lipid II — a highly conserved peptidoglycan precursor in the cytoplasmic membrane of bacteria — as their molecular target. The α-component (Lchα) of the two-component lantibiotic lichenicidin (Lchα), previously isolated from the Bacillus licheniformis VK21 strain, seems to contain two putative lipid II binding ...
Added: February 21, 2023
Victoria A. Vasileva,, Daria A. Mazur, Yury A. Budkov, Journal of Chemical Physics 2023 Vol. 159 No. 2 Article 024709
In this paper, we present a continuation of our research on modeling electrolyte solutions within charged pores. We make use of the model developed by Blossey et al. [Phys. Rev. E 95, 060602 (2017)], which takes into account the structural interactions between ions through a bilinear form over the gradients of local ionic concentrations in ...
Added: July 14, 2023
Wiley, 2022
Nitrogen-Rich Energetic Materials
Provides in-depth and comprehensive knowledge on both the chemistry and practical applications of nitrogen-rich energetic materials
Energetic materials, a class of material with high amounts of stored chemical energy, include explosives, pyrotechnics, and propellants. Initially used for military applications, nitrogen-rich energetic materials have become important in the civil engineering and aerospace sectors, they are ...
Added: January 31, 2023
Yurova P., Малахова В. Р., Gerasimova E. V. et al., Polymers 2021 Vol. 13 No. 15 P. 2513
Low chemical durability of proton exchange membranes is one the main factors limiting their lifetime in fuel cells. Ceria nanoparticles are the most common free radical scavengers. In this work, hybrid membranes based on Nafion-117 membrane and sulfonic or phosphoric acid functionalized ceria synthesized from various precursors were prepared by the in situ method for ...
Added: February 3, 2022
Budkov Y., Kolesnikov A. L., Polymer Science - Series C 2018 Vol. 60 No. Supplement 1 P. 148-159
Theoretical models of the conformational behavior of flexible polymer chains in mixed solvents enunciated in the world literature during the last decade are critically reviewed. Models describing different mechanisms of coil-to-globule transitions in a good solvent induced by cosolvent addition are highlighted. Special attention is given to the analysis of theoretical approaches to describing the ...
Added: November 30, 2018
Tatiana L. Kulova, Skundin A., Gavrilin I. M. et al., Batteries 2022 Vol. 8 No. 8 Article 98
Nanostructure composites Ge-Co-P with brutto-composition CoGe2P0.1, or CoGe2@GeP were manufactured via electrolysis of aqueous electrolyte. Such composites are able to reversible insertion of lithium and sodium with specific capacities up to 855 and 425 mAh/g, respectively. The main advantage of the composites consists in their excellent cycleability. ...
Added: November 25, 2022
Irina Stenina, Polina Minakova, Tatiana Kulova et al., Batteries 2022 Vol. 8 No. 9 Article 111
The influence of different conductive additives (carbon nanofibers (CNFs), carbonnanoplatelets, and pyrolytic carbon from sucrose (Sucr) or polyvinylidene fluoride) on the morphology, electron conductivity, and electrochemical performance of LiFePO4-based cathodes wasinvestigated to develop the most efficient strategy for the fabrication of high-rate cathodes. Pyrolyticcarbon effectively prevents the growth of LiFePO4 grains and provides contact between ...
Added: January 26, 2023