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Nukleofilowe podstawienie wodoru w nitroarenach. Proces analogiczny i komplementarny do podstawienia elektrofilowego

Mąkosza M.

Wiadomości Chemiczne

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2011

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[Z] 65, 9-10

795-819

EN

Nucleophiles add to electron-deficient arenes, also those containing halogens, initially in positions occupied by hydrogen to form óH adducts. This addition is faster than addition in similarly activated positions occupied by halogens. Formation of the óH adducts is a reversible process, thus they dissociate and slower addition in positions occupied by halogens results in formation of óH adducts followed by fast departure of X– to form products of nucleophilic substitution of halogen, SNAr. In the review it is shown that there are a few ways for fast further conversion of initially formed óH adducts into products of nucleopilic substitution of hydrogen such as oxidative substitution, vicarious substitution, etc. Since formation of óH adducts is faster than óH adducts and the former undergo fast transformations into products of nucleophilic substitution of hydrogen we should accept than this is the major, primary reaction whereas conventional nucleophilic substitution of halogens, SNAr reaction “ipso” substitution is just a secondary process. In modern textbooks only SNAr reactions are discussed whereas nucleophilic substitution of hydrogen is not mentioned, thus it is necessary to introduce proper corrections in textbooks and teaching of this chapter of chemistry of arenes.

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Synthesis and Characterization of Some 1-Halophenyl-4-nitroimidazoles

Jędrysiak R., Suwiński J.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 11

1935-1948

EN

Several 1-(chloro, fluoro, dichloro or difluorophenyl)-4-nitroimidazoles and their 2-methyl derivatives have been prepared by the reaction of respectively substituted anilines with 1,4-dinitroimidazoles via a degenerated imidazole ring transformation. The structures of the obtained products were characterized by spectros copy and/or by X-ray analysis. Most of the products have been tested as My cobacterium tuberculosis inhibitors.

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Oxidative Nucleophilic Substitution of Hydrogen in nitroarenes. A Short Review

Mąkosza M., Paszewski M.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 2

163-178

EN

Recent results of oxidative nucleophilic substitution of hydrogen in nitroarenes with carbon, nitrogen, oxygen etc. nucleophiles and discussion of oxidants used in these reactions are presented.

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Reversed imidazole nucleosides. Alternative pathway of synthesis

Walczak K., Suwiński J.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 6

1028-1036

EN

The reversed imidazole nucleosides were obtained on three independent routes: a) by the nucleophilic substitution of terminal tosylate group in sugar derivatives with imidazole-1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) salts, b) from monosugar derivatives with unprotected terminal hydroxy group and substituted imidazoles, under the Mitsunobu reactions conditions, c) by the reaction of monosugars possessing terminal primary amino group with 1,4-dinitroimidazoles. Limitation of these routes are discussed.