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Tandem Condensation/Rearrangement Reaction of 2-Aminohetarene N-Oxides for the Synthesis of Hetaryl Carbamates
Advanced Synthesis and Catalysis. 2018. Vol. 360. No. 16. P. 3157–3163.
A new approach to hetaryl carbamates through a tandem condensation/rearrangement reaction of 2-aminohetarene N-oxides was developed. The developed reaction is suitable for both five- and six-membered heterocycles and proceeds through the condensation of 2-aminohetarene N-oxide with trimethyl orthoformate followed by intramolecular N-oxide oxygen transfer. For five-membered hetarene N-oxides (furoxans), the intramolecular rearrangement is catalyzed by a cyanide anion, while for six-membered hetarene N-oxides (azines), Lewis acid catalysis is sufficient. The developed protocol is characterized by operational simplicity and high efficiency, resulting in carbamoyl derivatives in good and high yields.
Larin A. A., Fershtat L., Набатова А. et al., Russian Journal of Physical Chemistry B 2024 Vol. 18 P. 456–460
The decomposition rates of diphenylfuroxane and a number of 4-nitro-3-alkyl-furoxanes in dilute solutions are measured by the manometric and calorimetric methods. An increase in the reaction rate with an increase in the polarity of the solvent is not detected in any instance, which corresponds to the absence of an increase in the dipole moment of ...
Added: January 17, 2025
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
Voronin A., Sofya P. Balabanova, Fedyanin I. et al., Molecules 2022 Vol. 27 No. 19 Article 6287
A strategy for the synthesis of 5-((2-cyanoethyl)-X-amino)-[1,2,3]triazolo[4,5-c][1,2,5]oxadiazol-5-ium-4-ides (X = H; CH2CH2CN; NO2 (4a); CN (4b); CO2Et (4c)) starting from 3-amino-4-azido-1,2,5-oxadiazole was developed. The key step in this strategy is the intramolecular thermolytic cyclization of the azido group and the bis(2-cyanoethyl)triazene group. Removal of the 2-cyanoethyl protecting group from amides 4a–c gave potassium salt of the corresponding nitramide and ...
Added: January 31, 2023
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
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
Shirokova V., Smirnov A., Zaitseva E. et al., Chemistry Of Heterocyclic Compounds 2022 Vol. 58 P. 255–259
Added: June 19, 2022
Ivanov D., Zaitseva E., Smirnov A. et al., Advanced Synthesis and Catalysis 2022 Vol. 364 No. 9 P. 1587–1595
Added: June 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
Belousov Y., Drozdov A., Taydakov I. et al., Coordination Chemistry Reviews 2021 Vol. 15 Article 214084
The unique optical and magnetic properties of lanthanide ions (Ln), like a gem, need the right faceting and the right setting. Azole carboxylic acids provide a unique platform for driving the structure of complex compounds ranging in dimensions from 0-D (molecular complexes) to 1-D, 2-D polymers and 3-D MOF (Metal Organic Framework) structures. The peculiarity ...
Added: October 4, 2021
Belyy A., Platonov D., Salikov R. et al., Dyes and Pigments 2021 Vol. 187 Article 109107
A novel class of fluorescent electron-deficient 5-hydroxyisoquinolones is proposed. The new luminophores are obtained via the reaction of stable and easily available hepta(methoxycarbonyl)cycloheptatrienyl potassium with alkylamines, anilines and acylhydrazines. The new one-pot protocol is efficient with a large scope of primary amines. The solvolysis of N-acylamino substituted 5-hydroxyisoquinolones and subsequent reactions have provided a pathway ...
Added: September 29, 2021
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
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
Ostrovskis P., Mikhaylov Andrey A., Zard S., Organic Letters 2019 Vol. 21 No. 10 P. 3726–3729
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 ...
Added: September 29, 2020
Ananyev I., Топчий М., Зотова М. et al., Chemistry - A European Journal 2017 Vol. 23 No. 27 P. 6663–6674
An efficient and scaled-up synthesis of the imidazol-2-ylidene-based unsymmetrical NHC precursors bearing the sterically demanding hexafluoroisopropylalkoxy group [(CF3)(2)(OR)C-] at the ortho position of the N-aryl substituent was developed. The key step of the method involved the transformation of a Mes-substituted oxazolinium tetrafluoroborate salt through the reaction with the corresponding binucleophilic fluoroalkyl-substituted aniline. The subsequent post-modification ...
Added: October 4, 2019
Ananyev I., Ларин А., Муравьев Н. et al., Chemistry - A European Journal 2019 Vol. 25 No. 16 P. 4225–4233
A series of highly energetic organic salts comprising a tetrazolylfuroxan anion, explosophoric azido or azo functionalities, and nitrogen-rich cations were synthesized by simple, efficient, and scalable chemical routes. These energetic materials were fully characterized by IR and multinuclear NMR (H-1, C-13, N-14, N-15) spectroscopy, elemental analysis, and differential scanning calorimetry (DSC). Additionally, the structure of ...
Added: October 4, 2019
Galenko E., Galenko A., Novikov M. et al., ChemistrySelect 2017 Vol. 2 No. 25 P. 7508–7513
New β‐diazopyrrole and β‐triazenylpyrrole derivatives were synthesized from isoxazoles and pyridinium salts in two and three steps, respectively. The apoptotic/necrotic difference for these compounds was estimated on THP‐1 cell line. The most effective of the panel is methyl 3‐diazo‐2‐(2,4‐dimethylphenyl)‐4‐phenyl‐3H‐pyrrole‐5‐carboxylate which demonstrated cytotoxic activity from the lowest concentration of 3.3 μM with a steep rise of the ...
Added: June 25, 2019
Polyakov I. V., Вестник Московского университета. Серия 1: Математика. Механика 2012 Т. 1 № 6 С. 3–8
In this paper the rearranged Walsh system is considered. We prove that exists integrable function L o( sqrt ln+ L ) for which Fourier series with respect to the rearranged Walsh system diverges almost everywhere. ...
Added: April 2, 2013