A. Yu. Egorova

Azo coupling of 5-substituted furan-2(3H)-ones and 1H-pyrrol-2(3H)-ones with arene(hetarene)diazonium salts

Abstract5-Substituted furan-2(3H)-ones and 1-phenyl-1H-pyrrol-2(3H)-ones reacted with diazonium salts derived from substituted anilines and 1H-1,2,4-triazol-5-amine to give azo coupling products at the methylene group in the heteroring. The products were found to exist as hydrazone tautomers.

3-Arylidene derivatives of 3H-furan-2-ones. Synthesis and reaction with maleic anhydride

The synthesis of 5-alkyl(aryl)-3-arylidene-3H-furan-2-ones was accomplished, and their reaction with maleic anhydride was studied. The configuration of the initial arylidene derivatives was established on the basis of the PMR spectra of the adducts obtained.

Synthesis of 5-alkyl-3H-thiolen-2-ones and 5-alkyl-3H-furan-2-ones and condensation reactions at the heterocyclic methylene group

The intramolecular cyclization of γ-ketocarboxylic acids and their esters gives 5-alkylsubstituted 3H-thiolen-2-ones and 3H-furan-2-ones. It was shown that reaction occurred at the heterocyclic methylene group and that the conditions under which the reaction took place depended on the nature of the heterocyclic atom.

Reaction of 3-arylhydrazono-3H-furan-2-ones with o-phenylenediamine

Depending on the conditions, 3-arylhydrazono-3H-furan-2-ones reacted with o-phenylenediamine along two pathways with formation of 2-hydrazonotetrahydrobenzopyrrolo[1,2-a]imidazol-1-ones and 2-(1-aryl-1H-pyrazol-3-yl)benzimidazoles.

Synthesis of arylmethylidene(ethylidene)furanones

The data on the methods of synthesizing arylmethylidene(ethylidene) derivatives of 3H-furan-2-ones and related compounds based on the heterocyclization of different acids and their functional derivatives as well as the condensation of heterocyclic compounds with carbonyl components, are systematized in the review.

Common and Specific Features of the Michael Condensation in the Series of 3-R-3H-Furan-2-ones

The Michael condensation in the series of 5-aryl-3H-furan-2-ones with chalcones containing electron-donating substituents was studied. In the case of α,β-unsaturated ketones containing an electrondonating substituent, the reaction does not stop at the stage of formation of 1,5-dicarbonyl compounds but is accompanied by intramolecular cyclodehydration yielding a new series of furo[2,3-b]-4H-pyrans. A mechanism of formation of these products was suggested. The structure of reaction products was proved by IR and 1H NMR spectroscopy.

Modern Trends of Organic Chemistry in Russian Universities

This review is devoted to the scientific achievements of the departments of organic chemistry in higher schools of Russia within the past decade.

Reaction of 4-oxocarboxylic acids and 5-substituted 3H-furan-2-ones with 1,2-binucleophiles of aromatic and alicyclic series

Based on reactions of 5-substituted 3H-furan-2-ones or 4-oxocarboxylic acids with 1,2-binucleophiles of aromatic and aliphatic series methods were developed for the synthesis of tricyclic structures containing a pyrrolidine fragment fused with imidazolidine or oxazolidine ring. The pathways of the reactions are considered. It was demonstrated that the nature of the substrate did not affect the reaction direction, but changed the scheme of the interaction. The structures of compounds obtained for the first time were proved using IR and 1H NMR spectra.

Reaction of furan-2(3H)-ones with 1,2-binucleophiles

Reactions of 5-substituted furan-2(3H)-ones with ethylenediamine, 2-aminoethanol, and o-aminophenol do not stop at the stage of formation of the corresponding 4-oxoalkanoic acid amides but lead to new bi-and tricyclic structures as a result of double intramolecular cyclodehydration.

Synthesis of Arylidene Derivatives of 1-Aryl-3H-pyrrol-2-ones

The aminolysis of 5-aryl-3-arylidene-3H-furan-2-ones by the action of aromatic amines leads to the formation of substituted amides of 4-oxo acids, the subsequent azacyclization of which in the presence of acetic anhydride leads to the formation of 1,5-diaryl-substituted 3-arylidene-3H-pyrrol-2-ones. The mechanism of the occurring and alternative transformations is discussed.