Reaction of aromatic o-diamines with isatins. 3. 4-nitro- and 4,5-dinitro-o-phenylenediamines

The interaction of nitro-o-phenylenediamines with isatins yielded nitroindolo-[2,3-b] quinoxalines, 3-(2-aminophenyl)-2(1sH)-nitroquinoxalines, nitrospiro-[2H-benzimidazolin-2, 3-indolin]-2-ones, and Schiff bases. The position of the nitro group in the compounds obtained was demonstrated.For communication 2, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1544–1548, November, 1984.     

Reaction of o-phenylenediamine with isatins

It is shown that the reaction of o-phenylenediamine with isatins in the general case leads to mixtures of indolo[2,3-b]quinoxalines, 3-(2'-aminophenyl)-2(1H)-quinoxalinones, and spiro[2H-benzimidazoline-2,3'-indolin-2'-ones]. Spiro[2H-benzimidazole-2,3'-indolin-2'-ones] were isolated in individual cases.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 667–672, May, 1984.     

The nephelometric determination of selenium with 2,3-diaminonaphthalene

A nephelometric determination of selenium has been developed in the concentration range from 10 to 300 ppm based on the reaction of Se(IV) with 2,3-diaminonaphthalene. The method is inexpensive, simple, and requires little operator time or skill.     

Reaction of 2,3-epoxyoctafluorobutane with 2-aminobenzenethiol

The reaction of 2,3-epoxyoctafluorobutane with 2-aminobenzenethiol in N,N-dimethylacetamide gave 3-(2-aminophenylsulfanyl)-1,1,1,3,4,4,4-heptafluorobutane-2,2-diol. In the reaction of the same compounds in dioxane, 2,3-bis(trifluoromethyl)-3,4-dihydro-2H-1,4-benzothiazin-2-ol was formed as a result of primary attack by the amino group in 2-aminobenzenethiol on the epoxy ring. The same product was obtained by treatment with 2-aminobenzenethiol of 2,3-bis(trifluoromethyl)-2H-1,4-benzoxazin-2-ol which was synthesized from 2,3-epoxyoctafluorobutane and 2-aminophenol.     

Extraction-spectrophotometric determination of selenium in organoselenium compounds using aromatic o-diamines

Procedures for the extraction-spectrophotometric determination of selenium in organoselenium compounds using a new reagent, 1,2-diamino-3,4,5,6-tetrafluorobenzene (DAFB), and a known reagent, 2,3-diaminonaphthalene (DAN), are developed. Complexes of DAFB or DAN with selenium(IV) are extracted with toluene, and the absorbance of the extracts is measured. The optimal conditions for the determination were found, and the spectrophotometric characteristics were determined. The calibration curves are linear in the range of selenium concentrations of 1–10.6 mg/L (DAFB) and 1–9.1 mg/L (DAN). Nitrogen, chlorine, bromine, fluorine, and sulfur present in organoselenium compounds do not interfere with the determination of selenium. The relative error of determination does not exceed ±2%.     

Reaction of 2-methylene-2,3-dihydroindoles with acrylamide

1,3-Dihydrospiro[2H-indolo-2,2-piperidine] derivatives were obtained by the reaction of 2-methylene-2,3-dihydro-1H-indole derivatives with acrylamide in proton-containing solvents. 2-(3-Carbamoylpropyl)-3H-indolium perchlorates were formed when the 1,3-dihydrospiro[2H-indolo-2,2-piperidine] derivatives were treated with perchloric acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 902–904, July, 1988.     

Condensation of 1,3-diketones with 1,8-diaminonaphthalene: Synthesis ofbis(2,3-dihydroperimidine-2-spiro)cycloalkanes

Summary Cyclic 1,3-diketones like cyclopentane-1,3-dione, cyclohexane-1,3-dione, and 5,5-dimethylcyclohexane-1,3-dione react with 1,8-diaminonaphthalene to afford new condensed heterocyclic spiro systems.

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Kondensation von 1,3-Diketonen mit 1,8-Diaminonaphthalin: Synthese vonBis(2,3-dihydroperimidin-2-spiro)cycloalkanen

Zusammenfassung Cyclische 1,3-Diketone wie Cyclopentan-1,3-dion, Cyclohexan-1,3-dion und 5,5-Dimethylcyclohexan-1,3-dion reagieren mit 1,8-Diaminonaphthalin zu neuen kondensierten heterocyclischen Spiranen.

     

Reaction of l-methyl-2-cyanoindole with aromatic aldehydes

1-Methyl-2-cyanoindoles react with aromatic aldehydes in acidic media to give 1-methyl-2-cyano-3-(-halobenzyl)indoles. Replacement of the halogen by a cyano group gives (indolyl)-phenylacetonttrile, reduction of which gives the corresponding tryptamine. An attempt to replace the acetoxy group in 1-methyl-2-carbomethoxy-3-(-acetoxybenzyl)indole by a cyano group was accompanied by rearrangement to give 1-methyl-2-cyano-3-benzylindole.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 801–804, June, 1976.     

Five-membered 2,3-dioxo heterocycles. 21. Reaction of 1,5-diaryl-4-ethoxycarbonyl-tetrahydropyrrole-2,3-diones with 2-aminopyridine

The reaction of 2-aminopyridine with 1,5-diaryl-4-ethoxycarbonyltetrahydropyrrole-2,3-diones gave 11 complexes, which are converted to N-(2-pyridyl)-1,5-diaryl-3-hydroxy-2-oxo-2,5-dihydropyrrole-4-carboxamides when they are heated above their melting points without a solvent. The character of the hydrogen bonds in the complexes obtained is discussed.See [1] for Communication 20.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 32–36, January, 1992.     

Studies of the reactions between indole-2,3-diones (isatins) and 2-aminobenzylamine

Reflux of equimolecular amounts 2-aminobenzylamine and isatins in acetic acid produced indolo[3,2-c]quinolin-6-ones in good yields. A proposed mechanism involving initial formation of a spiro compound is given. This isolable intermediate subsequently rearranges via a sequential isocyanate ring opening and a cyclisation process to a urea derivative which finally cyclized to the indolo[3,2-c]quinolin-6-ones. The urea derivative could be prepared separately and cyclized selectively to indolo[3,2-c]quinolin-6-one. Reaction of N-acetylisatin with 2-aminobenzylamine at room temperature yielded the 1,4-benzodiazepinone 3-(2-acetamidophenyl)-1,5-dihydro-1,4-benzodiazepin-2-one whereas its isomer 2(2-acetamidophenyl)-4,5-dihydro-1,4-benzodiazepin-3-one was obtained from 2-(2-acetylaminophenyl)-N-(2-aminobenzyl)-2-oxoacetamide in acetic acid at room temperature.The previously unknown linear isomer of indolo[3,2-c]quinolin-6-one, i.e. indolo[2,3-b]quinolin-11-one, has been prepared by thermal (260°C) cyclization of methyl 2-phenylamino indole-3-carboxylate, which in turn was prepared in two steps from methyl indole-3-carboxylate.     

Fluorescent derivatization of nitrite ions with 2,3-diaminonaphthalene utilizing a pH gradient in a Y-shaped microchannel.

The on-chip derivatization of nitrite ions with 2,3-diaminonaphthalene (DAN) utilizing a pH gradient formed in a Y-shaped microchannel was investigated. Nitrite ions react with DAN at low pH, and strongly fluoresced at high pH. Therefore, a reaction at low pH followed by the addition of a strong alkaline solution is the usual procedure in a batch scheme. However, a strong alkaline solution, like an NaOH aqueous solution, erodes the wall of the microchannels in substrates made of glass or polymers, and has not been considered suitable for use in microchannels. We first investigated the derivatization reaction and fluorescent properties of nitrite ions with DAN. We found that the on-chip fluorescent derivatization reaction and detection without the addition of an alkaline solution is possible by controlling the pH values of the nitrite solution and the DAN solution to form a suitable pH gradient by utilizing a buffering effect of triethanolamine solution, which is used as an NO2 gas-absorption medium. These results have suggested the feasibility of novel reaction schemes which can provide the desired products due to a controlled pH gradient in the microchannels, as well as the possibility of an on-site monitoring microchip device for ambient NO2.     

Five-membered 2,3-dioxoheterocycles. 28. Reaction of 5-aryl-2,3-dihydrofuran-2,3-diones with thioamides and thiosemicarbazides

The reaction of 5-aryl-2,3-dihydrofuran-2,3-diones (I) with thiocarbonyl compounds has been described only for thiourea. The products of this reaction are 3-aryl-5-phenacylidene-4-oxoimidazolidine-2-thiones [2]. It seemed of interest to study the conversion of the furandiones (I) with a wider range of thiocarbonyl compounds such as thioamides and thiosemicarbazides.For Communication 27 see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1461–1464, November, 1992.     

Reaction of 2,3-tetramethylen-3,4-dihydroquinazol-4-one and its derivatives with aromatic aldehydes and furfurol

α-Aryliden-6H(nitro)- and 6,8-dibromo-2,3-tetramethylen-3,4-dihydroquinazol-4-ones were synthesized by condensation of 6H(nitro)- and 6,8-dibromo-2,3-tetramethylen-3,4-dihydroquinazol-4-ones with aromatic aldehydes, furfurol, and of α-formyl-2,3-tetramethylen-3,4-dihydroquinazol-4-one with benzaldehyde and 4-nitrobenzaldehyde in glacial acetic acid. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 342-347, May-June 2009.