Chemistry of indole

5-Methoxy-3-carbethoxyindoles are nitrated primarily in the 4 position. Replacement of the methoxy group by an acetoxy group leads to a change in orientation — only the 6 isomer is obtained. In the case of the similarly constructed 5-hydroxyindoles, monosubstitution cannot be accomplished under various conditions, and only the 4,6-dinitro derivative is formed. The synthesis of the corresponding amines by reduction of the nitro compounds is described.See [1] for communication XXXVIII.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1646–1653, December, 1973.     

Investigation of low-temperature regeneration of activated carbon

Granular activated carbon loaded with aniline,o-nitroaniline oro-nitrophenol, regenerated at relatively low temperature (450° in N₂ atmosphere), shows losses of cyclic adsorption performances (about 5 % per cycle) comparable to those occurring with standard thermal regeneration (950° in controlled atmosphere). Adsorbate build-ups and related surface modifications have been determined.

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Zusammenfassung Mit Anilin,o-Nitroanilin undo-Nitrophenol beladene, bei relativ niedriger Temperatur (450° in N₂-Atmosphäre) regenerierte granulierte Aktivkohle, zeigt zyklische Verluste der Adsorptionsleistung (etwa 5 % je Zyklus), welche mit den bei thermischer Standard-Regenerierung (950° in gesteuerter Atmosphäre) vorkommenden vergleichbar sind. Der Aufbau der Adsorbate und die damit verbundenen Oberflächenänderungen wurden bestimmt.

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Résumé Le charbon actif en granulés, chargé d'aniline, d'o-nitroaniline et d'o-nitrophénol, régénéré à une température relativement faible (450° dans une atmosphère d'azote) montre des pertes de rendement d'adsorption cyclique (environ 5 p.c. par cycle) comparables à celles qui ont lieu lors de la régénération thermique standard (950° en atmosphère contrôlée). On a déterminé la constitution des adsorbats et les modifications relatives de surface.

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, , -, - – 450° . , ( 5% ) – 950° . .

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Work supported by IRSA-CNR, contract no. 77.01823.11.

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Thanks are due to Mr. L. Pace for skilful contribution to the experimental work.     

Stabilization of reaction products of ureas with polyfluoro ketones

Conclusions Polyfluorinated tetrahydro-1,3,5-oxadiazine derivatives were obtained by the condensation of urea and thiourea with polyfluoro ketones.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2168–2169, September, 1977.     

Einführung von Carboxylgruppen in vernetztes Polystyrol

Ohne Zusammenfassung     

Reaction of gaseous hydrogen fluoride with aluminium and its compounds

The reaction of metallic aluminium surfaces, aluminium oxides, hydrated oxides and sulphate with gaseous anhydrous hydrogen fluoride was studied at 470°C and pressures between 10 and 100 torr. The complementary analytical techniques of X-ray induced photoelectron spectra, X-ray and electron diffraction, and electron microscopy were used for identifying the (frequently unexpected) products.     

The lowest triplet state of benzene: Differences in electronic structure in two crystalline modifications of a cyclohexane host

Microwave induced delayed phosphorescence (MIDP) measurements have been performed in the 00 bands of the phosphorescence spectrum of benzene dissolved in two phases of cyclohexane. From the relative radiative rates for decay of the three zero-field levels it is concluded that on the average the symmetry of the electronic structure is lower than D_2h. In the monoclinic low temperature stable phase of cyclohexane (phase II) the structure is approximately antiquinoidal, and in the metastable phase III it is approximately quinoidal.     

Dissociative ionization of methyl-substituted hydroxyquinolines

The mass spectra of the following methyl-substituted hydroxyquinolines have been studied in the range of energies of the ionizing electrons of 15–50 eV: 2-hydroxy-4-methylquinoline, 6-hydroxy-2-methylquinoline, 6-hydroxy-4-methylquinoline, 8-hydroxy-2-methylquinoline, 8-hydroxy-4-methylquinoline, 2,6-dihydroxy-4-methylquinoline, and 4,6-dihydroxy-2-methylquinoline. It has been shown that the processes of dissociative ionization for the series of compounds investigated take place exclusively from the keto forms of the molecular ions. The stability to electron impact is determined largely by the degree of enolization of the structures considered. The values of the selective decomposition are given and a scheme is proposed for the identification of the isomeric methyl-substituted hydroxyquinolines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 972–978, July, 1973.