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Route to 1,2,4-and 1,2,5-oxadiazole ring assemblies via a one-pot condensation/oxidation protocol
Tetrahedron Letters. 2020. Vol. 61. No. 13. P. 151678-1-151678-5.
A novel one-pot approach for the synthesis of 1,2,4- and 1,2,5-oxadiazole ring assemblies has been developed. The synthetic strategy involves the condensation of furoxanyl amidoximes with aldehydes and subsequent iodine-mediated oxidation of the intermediate 1,2,4-oxadiazolines. The analogous reaction of 4-aminofuroxanyl-3-carboxamidoxime results not only in formation of the 1,2,4-oxadiazole subunit, but also rearrangement of the furoxan ring to the furazan one, which is the first example of a Lewis acid-promoted rearrangement in a furoxan series
Zhilin E., Ivan V. Ananyev, Pivkina A. et al., Dalton Transactions 2022 Vol. 51 No. 37 P. 14088-14096
Nitrogen-oxygen organic materials constitute an important family of multipurpose high-energy materials. However, the preparation of energetic boosters and oxidizers for various civil and space technologies remains a challenging task and such materials usually require special precautions and fine tunability of their functional properties. To find a balance between energy and safety while retaining the oxidizing ...
Added: October 24, 2022
Nizovtsev A., Sokolov A., Smirnov A. et al., ChemistrySelect 2021 Vol. 6 No. 34 P. 8938-8941
Herein we report a short and general protocol for synthesis of potentially biologically active pyridine-2,6-diones. The approach is based on the redirection of the condensation of the intermediates of Dornow reaction – 5-hydroxy-1,2-oxazine-6-ones with primary amines by their prior O-alkylation. Such manipulation blocks their transformation into isoxazoles and allows one to obtain a library of 30+ ...
Added: September 9, 2021
Stebletsova I., Alexander A. Larin, Ivan V. Ananyev et al., Molecules 2023 Vol. 28 No. 19 Article 6969
A facile and efficient method for the regioselective [3 + 2] cycloaddition of 4-azidofuroxans to 1-dimethylamino-2-nitroethylene under p-TSA catalysis affording (4-nitro-1,2,3-triazolyl)furoxans was developed. This transformation is believed to proceed via eliminative azide–olefin cycloaddition resulting in its complete regioselectivity. The developed protocol has a broad substrate scope and enables a straightforward assembly of the 4-nitro-1,2,3-triazole motif. Moreover, ...
Added: October 12, 2023
Larin A., Shaferov A., Epishina M. et al., ACS Applied Energy Materials 2020 Vol. 3 No. 8 P. 7764-7771
Several energy-rich bifuroxans incorporating nitro and azido functionalities have been synthesized and thoroughly characterized by IR and multinuclear NMR spectroscopy, elemental analyses, single-crystal X-ray diffraction, and differential scanning calorimetry. N-oxide regiochemistry was employed to design the tunable azido(nitro)bifuroxans with different physicochemical and energetic properties. All synthesized compounds have high enthalpies of formation (449-777 kJ mol(-1)) ...
Added: April 12, 2021
Ikonnikova V., Baranov M., Mikhaylov A. A., European Journal of Organic Chemistry 2022 Vol. 2022 No. 31 Article e202200675
The review in a critical manner analyzes developments in
the synthesis of hasubanan alkaloids with the focus on construction
of hasubaban core. Historical and recent reports are systemized
based on the strategic bonds formation and are given in comparison.
Special accents are made on the achievements in collective
syntheses, asymmetric syntheses and biomimetic approaches.
Based on the summarized data potential perspectives ...
Added: July 19, 2022
Larin A., Shaferov A., Kulikov A. et al., Chemistry - A European Journal 2021 Vol. 27 P. 14628-14637
cA series of novel energetic materials comprising of azo-bridged furoxanylazoles enriched with energetic functionalities was designed and synthesized. These high-energy materials were thoroughly characterized by IR and multinuclear NMR (1H, 13C, 14N) spectroscopy, high-resolution mass spectrometry, elemental analysis, and differential scanning calorimetry (DSC). The molecular structures of representative amino and azo oxadiazole assemblies were additionally confirmed by ...
Added: October 13, 2021
Smirnov A., Zaitseva E., Belozerova O. et al., Journal of Organic Chemistry 2019 Vol. 84 No. 23 P. 15417-15428
An efficient and high-yielding strategy to prepare “unsymmetrical” 4-aryl-isoxazol-3,5-dicarboxylic acid derivatives from nitroacetic esters and aromatic aldehydes has been developed. The strategy is based on the isolation and usage of the previously missed intermediate of the Dornow reaction—5-hydroxy-6-oxo-4-aryl-6H-1,2-oxazine-3-carboxylates. In addition, the mechanism of the Dornow reaction was partially revised. ...
Added: September 29, 2020
Anikin O., Leonov N., Klenov M. et al., European Journal of Organic Chemistry 2019 No. 26 P. 4189-4195
7‐Nitro‐3‐(nitro‐NNO‐azoxy)[1,2,4]triazolo[5,1‐c][1,2,4]‐triazin‐4‐amine (4) is the first high‐melting compound bearing adjacent nitro‐NNO‐azoxy and amino groups. It was synthesized by nitration of 7‐nitro‐3‐(tert‐butyl‐NNO‐azoxy)[1,2,4]triazolo[5,1‐c][1,2,4]triazin‐4‐amine (3) with NO2BF4. Compound 4 is a rather thermally stable (decomposition onset temperature 154 °C), highly energetic (calculated heat of formation 580 kcal·kg–1), and highly dense (1.875 g cm–3) material with a CO‐level oxygen balance. ...
Added: October 15, 2020
Fershtat, Leonid L., Teslenko F., Synthesis 2021 Vol. 53 No. 20 P. 3673-3682
Five-membered heterocyclic N-oxides attract special attention due to their significant potential applications in medicinal chemistry and advanced materials science. In this regard, novel methods for their synthesis and functionalization are in constant demand. In this short review, recent state-of-the-art achievements in the chemistry of isoxazoline N-oxides, 1,2,3-triazole 1-oxides and 1,2,5-oxadiazole 2-oxides are summarized. The main ...
Added: September 12, 2022
Svetlana S. Degtyareva, Bardonov D., Afanaseva A. et al., Inorganic Chemistry 2024 Vol. 63 No. 4 P. 1867-1878
LnCl3(THF)3 (Ln = Y, La ÷ Nd, Sm ÷ Lu) легко реагируют с тридентатным 1,3,5-триметил-1,3,5-триазациклогексаном
(Me3tach) лигандом с образованием моно- или биядерных трихлоридных комплексов лантанидов, в зависимости от стехиометрии реакции и
ионного радиуса металла: моноядерный псевдосэндвич [LnCl3(Me3tach)2], (Ln = Y, La ÷ Ho) или биядерные комплексы
[Ln2Cl6(Me3tach)3], или [LnCl3(Me3tach)(THF)]2 (Ln = Sm, Tb). Детальный анализ данных ЯМР [LnCl3(Me3tach)2]
комплексов ...
Added: February 1, 2024
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
Чаплыгин D., Gorbunov Y., Leonid L. Fershtat, Asian Journal of Organic Chemistry 2021 Vol. 10 No. 10 P. 2644-2653
A regioselective method for an assembly of pharmacologically relevant fully substituted furoxans and isoxazoles using the ring distortion diversity-oriented approach through the one-pot ring cleavage/nucleophilic addition/oxidation cascade of monosubstituted furoxans was developed. The described synthetic strategy is highly regioselective and provides single furoxan regioisomers upon utilization of N- or S-nucleophiles. Utilization of the cyanide-anion as ...
Added: September 12, 2022
Reznichenko Y. S., Dubinskii A. Y., Popel S. I., Journal of Physics: Conference Series 2020 Vol. 1556 P. 012072
A self-consistent model for the formation and evolution of dusty plasmas in the Martian ionosphere is developed. The effects of the initial distributions of dust particles, as well as condensation and absorption of carbon dioxide and water molecules by dust particles, are studied. Theory values of characteristic sizes of dust grains and their charges are obtained. The theoretical values ...
Added: July 7, 2020
Fedorenko A., Ivanova V., Minyaev M. E. et al., ChemistrySelect 2023 Vol. 8 No. 43 Article e202303122
General method for the annulation of [1,2,5]thiadiazole ring to pyridine and benzene cycle has been developed using sulfur monochloride as a sulfur source. On this basis a number of [1,2,5]thiadiazolo[4,3-b]pyridines and benzo[c]thiadiazoles were synthesized. The most π-deficient [1,2,5]thiadiazolo[4,3-b]pyridines readily react with neutral carbon nucleophiles such as CH-acids, indoles, pyrrole and phloroglucinol to give 1,4-adducts. ...
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
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
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
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
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
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
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
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
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