Effects of adsorbed bismuth on Si(001) surface electronic states

It is shown that depositing Bi on an Si(001) surface fills the free broken-bond surface states, whose concentration decreases linearly as the bismuth coating 8 increases up to _st, = 0.6 monolayer. The bismuth desorption activation energy is constant < _st, (E_d = 2.77 ± 0.1 eV) and decreases for > _st.Taras Shevachenko Kiev National University, ul. Vladimirskaya 64, 252601 Kiev-17, Ukraine. Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 32, No. 3, pp. 168–171, May–June, 1996. Original article submitted September 19, 1995.     

Acid-base properties of 1-acyl-5-hydroxypyrazolidines in a hydrogen bond

In solutions, 1-acyl-5-hydroxypyrazolidines form only intermolecular hydrogen bonds in which the proton acceptor is the oxygen atom of the hydroxyl group. These compounds are similar to phenols with respect to the acidity in a hydrogen bond.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 936–939, July, 1989.     

Addition of thiophenols and arylamines to dibenzo[a,j]-phenoxazin-9-one

Thiophenols undergo nucleophilic addition to dibenzo[a,j]phenoxazin-9-one (II) in position 5, forming 5-arylthiodibenzo[a,j]phenoxazin-9-ones (III–V). With arylamines in the presence of their hydrochlorides,II is converted on heating into N-aryldibenzo[a,j]phenazine derivatives.     

New methods for the synthesis of amides of benzo[b]thiophene-2carboxylic acid

The reaction of 3-bromothiocoumarin with nitrogen bases, during which the thiocoumarin system is converted to a benzothiophene system, was studied. A new method for the synthesis of amides of benzo[b]thiophene-2-carboxylic acid is proposed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1340–1342, October, 1978.     

Catalytic methods for obtaining thiophene and alkylthiophenes from petroleum refining products and sulfur-containing organic compounds

This review is devoted to catalytic methods for obtaining thiophene and alkylthiophenes from C₂-C₆ hydrocarbons and from various organosulfur compounds — aliphatic sulfides, mercaptans, alkylthiophenes, thiophane, and sulfones. Multicomponent chromium-containing catalysts have considerable activity in the majority of the reactions. The catalytic method for obtaining thiophene and alkylthiophenes by the reaction of C₂-C₆ hydrocarbons with hydrogen sulfide may be the most promising one.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1299–1312, October, 1971.     

The oxidation of organic compounds

In a study of the behavior of tris(hydroxymethyl)-4-picoline (I) under the conditions of vapor-phase oxidation on a vanadium-tin oxide catalyst, it was found that with the addition of 150–250 mole of water and 125–200 mole of O₂ per mole of I and a contact time of 0.35–0.45 sec, the main reaction product was isonicotinic acid (II), the yield of which amounted to 60–65% of theoretical, calculated on the I passed.For part XLVIII, see [1].     

Chemistry of phenoxazines

Benzo[c]phenoxazin-3-one was synthesized, and the IR and electronic absorption spectra of phenoxazin-3-one and six of its benzo derivatives were studied.See [1] for communication I.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 742–745, June, 1971.     

Isomerization of butane catalyzed by CH3COX·2AlX3

Conclusions AcX·2AlX₃ (X=Br, Cl) are efficient catalysts for the isomerization of butane at room temperature. The activity of these catalysts is superior to that of known catalytic systems.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1416–1419, June, 1986.     

New organic two-dimensional metals, (ET)4(Hg2X6)·PhCl (X=Cl,Br)

Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2872–2873, December, 1990.