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Synthesis of Trifluoromethylated Spiroisoxazolones via a [3+2] Cycloaddition of Nitrile Imines and Unsaturated Isoxazolones [PDF]
MoleculesA strategy for constructing trifluoromethylated spiroisoxazolones has been developed. This approach relies on the 1,3-dipolar cycloaddition of CF3-substituted nitrile imines, generated in situ from trifluoroacetyl hydrazonoyl bromides and K2CO3, with the
Wei Zhang, Da-Ming Du
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Molecules, 2021 1,3-Dipolar cycloaddition reactions of 2-substituted 5-R-3-nitropyridines and isomeric 3-R-5-nitropyridines with N-methyl azomethine ylide were studied. The effect of the substituent at positions 2 and 5 of the pyridine ring on the possibility of the [3 ...
Maxim A. Bastrakov +3 more
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Molecules, 2022 The 1,3-dipolar cycloaddition of 1,2-dithiole-3-thiones with alkynes to form 1,3-dithioles is one of the most studied reactions in this class of polysulfur-containing heterocycles. Nucleophilic substitution of chlorine atoms in dimethyl 2-(1,2-dichloro-2-
Vladimir A. Ogurtsov, Oleg A. Rakitin
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Fluorescent Azasteroids through Ultrasound Assisted Cycloaddition Reactions
Molecules, 2021 We report here the synthesis and optical spectral properties of several new azasteroid derivatives. The formation of these compounds was explained based on the most probable mechanism.
Costel Moldoveanu +2 more
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Beilstein Journal of Organic Chemistry, 2022 A reliable method for the synthesis of bis-spirocyclic derivatives of 3-azabicyclo[3.1.0]hexanes through the 1,3-dipolar cycloaddition (1,3-DC) reactions of cyclopropenes to the stable azomethine ylide – protonated form of Ruhemann's purple (PRP) has ...
Alexander S. Filatov +4 more
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Molecules, 2021 In this study, 3-benzoylisoxazolines were synthesized by reacting alkenes with various α-nitroketones using chloramine-T as the base. The scope of α-nitroketones and alkenes is extensive, including different alkenes and alkynes to form various ...
Xinhui Pan +8 more
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On the strong difference in reactivity of acyclic and cyclic diazodiketones with thioketones: experimental results and quantum-chemical interpretation [PDF]
, 2015 The 1,3-dipolar cycloaddition of acyclic 2-diazo-1,3-dicarbonyl compounds (DDC) and thioketones preferably occurs with Z,Econformers and leads to the formation of transient thiocarbonyl ylides in two stages.
Holleman +8 more
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SynOpen, 2017 A variety of sugar-fused chromanono pyrrolidines/pyrrolizidines/thiolizidines have been synthesized by intermolecular 1,3-dipolar cycloaddition reaction of azomethine ylides (generated from glucose aldehyde and different secondary amino acids) with ...
Sirisha Nallamala +2 more
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Synthesis of novel pyrazoles via [2+3]-dipolar cycloaddition using alkyne surrogates [PDF]
Tetrahedron Letters, 2010 The syntheses of an important class of hitherto unreported novel pyrazoles are described. The regioselective synthesis of 1,3,4,5-tetrasubstituted pyrazoles was achieved by the Huisgen cyclization of nitrile imines with a trisubstituted bromoalkene. The substituted bromoalkene functions as an alkyne synthon which was used to construct 5,5-disubstituted
Sureshbabu, Dadiboyena +2 more
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Synthesis of pyrrolizines by intramolecular capture of 1,4-dipolar intermediates in reactions of enamines with dimethyl acetylenedicarboxylate [PDF]
, 1981 Solvent polarity and reaction temperature strongly influence the reactions of dimethyl acetylenedicar-boxylate (DMAD) with 1-pyrrolidinyl enamines of acyclic and cyclic ketones. Whereas DMAD and 1-[1-phenyl-2-(phenylthio)ethenyl]pyrrolidine (3) give only
Harkema, S. +5 more
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