Results 1 to 10 of about 17,890 (211)
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
doaj +1 more source
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
doaj +1 more source
Fluorescent Azasteroids through Ultrasound Assisted Cycloaddition Reactions
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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On the strong difference in reactivity of acyclic and cyclic diazodiketones with thioketones: experimental results and quantum-chemical interpretation [PDF]
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
core +7 more sources
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
doaj +1 more source
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
doaj +1 more source
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
doaj +1 more source
Synthesis of novel pyrazoles via [2+3]-dipolar cycloaddition using alkyne surrogates [PDF]
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
openaire +2 more sources
The regiochemistry of 1,3-dipolar cycloaddition reactions of E-3-(dimethylamino)-1-(10H-phenothiazin-2-yl) prop-2-en-1-one with some nitrilimines were investigated using density functional theory (DFT) -based reactivity indexes, activation energy ...
Farid Moeinpour, Amir Khojastehnezhad
doaj +1 more source
Synthesis of 1,4-Disubstituted Mono and Bis-triazolocarbo-acyclonucleoside Analogues of 9-(4-Hydroxybutyl)guanine by Cu(I)-Catalyzed Click Azide-Alkyne Cycloaddition [PDF]
A series of novel mono-1,2,3-triazole and bis-1,2,3-triazole acyclonucleoside analogues of 9-(4-hydroxybutyl)guanine was prepared via copper(I)-catalyzed 1,3-dipolar cycloaddition of N-9 propargylpurine, N-1-propargylpyrimidines/as-triazine with the ...
Engels, Joachim W. +2 more
core +2 more sources

