Studies in the imidazole series

Кочергин, П. М.; Tsyganova, A. M.; Shilikhunova, V. S.; Klykov, M. A.

doi:10.1007/bf00945516

Cited by 5 publications

(7 citation statements)

References 3 publications

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“…In [19] it was noted that 5-bromo-1,2-dimethyl-4-nitroimidazole, unlike its 4-bromo-5-nitro isomer, does not react with alcoholates, contradicting the experimental data from other authors [12][13][14][15][16][17][18].…”

Section: Reactions With O-nucleophilesmentioning

confidence: 96%

“…NH 2 NH 2 4-Halo-5-nitroimidazoles enter into reaction similarly with N-nucleophiles. The reactions of compounds 52 with ammonia [55], amines [14,19,22,58], amino alcohols [19,59], amino acids [60], and derivatives of imidazole with a free NH group [20,59] An unusual reaction with N-nucleophiles, during which not only the halogen atom but also the NO 2 group is substituted by the N-nucleophile fragment, was described in the series of halonitro derivatives of imidazole and 2,2'-diimidazole. Thus, 4,4',5,5'-tetraphenylamino-2,2'-diimidazole was obtained when 4,4'-dibromo-5,5'-dinitro-2,2'-diimidazole was boiled in aniline [66].…”

Section: Reactions With N-nucleophilesmentioning

confidence: 99%

“…5-Halo-4-nitroimidazoles 13 react with ammonia [55], primary [16-18, 21, 56] and secondary [14,19,[56][57][58] amines, dialkylaminoalkylamines [16,17,20,56], amino alcohols [19,59], aminophenols [21], amino acids [60], and heterocyclic compounds containing a free NH group [20,57]. A large series of 5-amino-4-nitroimidazole derivatives 41-43 were synthesized as a result of these reactions.…”

Section: Reactions With N-nucleophilesmentioning

confidence: 99%

“…A series of 5-iodo-4-nitroimidazoles 14 were obtained by the reaction of 5-chloro(bromo)-4-nitroimidazoles 13 with potassium iodide [14]. …”

Section: °Cmentioning

confidence: 99%

“…The reaction of 5-halo-4-nitroimidazoles 13 with NaOH leads to the sodium salts of 5-hydroxy-4-nitroimidazoles 15 [14], while the reaction with sodium alcoholates leads to 5-alkoxy-4-nitroimidazoles 16 [12][13][14][15][16][17][18].…”

Section: Reactions With O-nucleophilesmentioning

confidence: 99%

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Reactions of halonitroimidazoles with nucleophiles (review)

Александрова¹,

Кравченко

Кочергин³

2010

Chem Heterocycl Comp

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On account of their chemical stability, high reactivity, and availability 4(5)-halo-5(4)-nitro-and 2-halo-4(5)-nitroimidazoles have proved useful substrates for the study of reactions with O-, S-, N-, C-, and N,O-nucleophiles. The high reactivity of the halogen atom in the series of 4(5)-halo-5(4)-nitroimidazoles is brought about by the presence of the strong electron-accepting NO 2 group at the "ortho" position. The activating effect of the NO 2 group also extends to the halogen atom at position 2 of the imidazole ring.The products from the reactions of halonitroimidazoles with various nucleophiles have found use in fine organic synthesis, especially in the synthesis of heterocycles with a bridging nitrogen atom, biologically active compounds, and medicinal preparation. Thus, 1-methyl-4-nitro-5-(6-purinyl)mercaptoimidazole has found use under the name azathioprine as a medical preparations in the transplantation of vital organs and the treatment of a series of autoimmune diseases [1][2][3][4].

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Section: Reactions With O-nucleophilesmentioning

confidence: 96%

Section: Reactions With N-nucleophilesmentioning

confidence: 99%

Section: Reactions With N-nucleophilesmentioning

confidence: 99%

“…A series of 5-iodo-4-nitroimidazoles 14 were obtained by the reaction of 5-chloro(bromo)-4-nitroimidazoles 13 with potassium iodide [14]. …”

Section: °Cmentioning

confidence: 99%

Section: Reactions With O-nucleophilesmentioning

confidence: 99%

See 3 more Smart Citations

Reactions of halonitroimidazoles with nucleophiles (review)

Александрова¹,

Кравченко

Кочергин³

2010

Chem Heterocycl Comp

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4,5‐Bis(dialkylamino)‐Substituted Imidazolium Systems: Facile Access to N‐Heterocyclic Carbenes with Self‐Umpolung Option

Huber¹,

Heinemann²,

Audebert

et al. 2011

Chemistry A European J

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The first synthesis of 4,5-bis-(dimethylamino)-substituted imidazolium compounds was developed, which is based on the reaction of a 1,2-diamino-1,2-bis(phosphonio)ethene with lithiated formamidines. This represents the first application of this class of ethene derivatives for the preparation of heterocycles. These N-heterocyclic carbene (NHC) precursors show a remarkably reduced basicity and nucleophilicity of their NMe2 groups, which is due to the strong anomeric interactions of the latter with the imidazolium core. According to DFT calculations, these NHCs are capable of self-umpolung if sufficiently strong acceptor substituents are introduced at the carbene center. To test the self-umpolung capabilities of the NHCs, various substituents were attached to the carbene center and the obtained compounds were characterized by single-crystal X-ray analysis as well as quantum chemical computations. Strong acceptor substituents are required to induce self-umpolung, such as in the phosphonio-substituted derivative, for which partial self-umpolung was found. The N,N′-bis(4-dimethylaminophenyl)-substituted imidazolium compound represents a special case, as it incorporates as much as three two-step redox systems within the NHC framework. This will probably result in a high electronic flexibility of the corresponding nucleophilic carbenes, especially when they serve as ligands in transition metal complexes.

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