Phenoxathin chemistry. Remarks concerning the benzoylation reaction of phenoxathin

Benzoylation of phenoxathiin leads to a mixture of 2- and 3-benzoylphenoxathiins. Starting from 3-phenoxathiincarbonyl chloride and benzene in the presence of anhydrous aluminum chloride, 2-benzoylphenoxathiin was obtained instead of the 3-substituted isomer. Treating 3-benzoylphenoxathiin with aluminum chloride and hydrogen chloride a rearrangement reaction took place, leading to 2-benzoylphenoxathiin.Faculty of Chemistry, Organic Chemistry Department, University of Bucharest, 90–92 Panduri Road, Romania 76233. Romanian Academy, C. D. Nenitzescu Institute of Organic Chemistry, Splaiul Independentei, 202, Bucharest, Romania. Faculty of Pharmacy, Organic Chemistry Department, University of Medicine and Pharmacy Carol Davila, 6 Traian Vuia Street, Bucharest, Romania. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 999–1003, July, 1998.     

The beginnings of Analytical Chemistry in Romania

The early time of Analytical Chemistry in Romania is presented. Starting from 1920, the famous schools of chemical analysis in the University of Cluj, Bucharest and Iassy were established. As an example, the team headed by Professor G. Spacu introduced the use of complex compounds as reagents in analytical chemistry. In this way many macro and micro gravimetric methods for elemental determination were proposed. Received: 1 March 1996 / Accepted: 20 May 1996     

The beginnings of Analytical Chemistry in Romania

The early time of Analytical Chemistry in Romania is presented. Starting from 1920, the famous schools of chemical analysis in the University of Cluj, Bucharest and Iassy were established. As an example, the team headed by Professor G. Spacu introduced the use of complex compounds as reagents in analytical chemistry. In this way many macro and micro gravimetric methods for elemental determination were proposed. Received: 1 March 1996 / Accepted: 20 May 1996     

Synthesis of 1H-pyrrolo[2,3-b]phenoxathiin-2,3-dione

The title compound was obtained using the Sandmeyer reaction starting from 2-aminophenoxathiine. A new synthesis of N-methylpyrrolo[2,3-b]phenoxathiin-2,3-dione was also presented. Chemical and spectral data supporting the structure of the newly synthesized compounds were given. The isatin analogue, 1-methylpyrrolo-[2,3-b]phenoxathiin-2,3-dione-10, 10-dioxide, could not be obtained.Faculty of Chemistry, Organic Chemistry Department, University of Bucharest, 90–92 Panduri Road, Romania. Faculty of Pharmacy, Organic Chemistry Department, University of Medicine and Pharmacy Carol Davila, Bucharest, Romania. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 396–399, March, 1998.     

Temporal trends of carbon monoxide (CO) and radon (222Rn) tracers of urban air pollution

Journal of Radioanalytical and Nuclear Chemistry - The use of carbon monoxide (CO) and radon (222Rn) during 1 year continuous monitoring in Bucharest, Romania in relation with other air...     

The effect ofn-butyl glycol ethers on the phase diagrams of microemulsions formulated with nonionic surfactants

The effect ofn-butyl glycol ethers used as cosurfactants on the microemulsions formulated with two nonionic surfactants, hexaoxyethylene glycol monolauryl ether and sorbitan monolaurate, is presented on ternary phase diagrams. The solubilization parameters as well as isothermal invariant points (IIP) of microemulsions were correlated with the solubility parameters of cosurfactants. An optimum solubility parameter of cosurfactants was established around 9 (cal/cm³)^1/2 where both IIP and solubilization parameters are optimal for water and oil solubilization with the lowest concentration of amphiphilic compounds. The mixture of cosurfactants can be used to obtain a certain transition on the phase diagram and so to achieve certain characteristics for microemulsions, especially to tailor the solvency of the system.On leave from the University of Bucharest Department of Physical Chemistry Bdul Republicii 13 Bucharest, Romania     

Naphthomoles. 7. Synthesis of 4,11-dimethoxynaphtho[2,3-f]indole-5,10-dione and 4-methoxynaphtho[2,3-f]-indole-5,10-dione

4,11-Dimethoxynaphtho[2,3-f]indole-5,10-dione and 4-methoxynaphtho[2,3-f[indole-5,10-dione have been synthesized by the Leimgruber-Batcho reaction from 1,4-dimethoxy-2-methyl-3-nitroanthraquinone.Russian University of Chemical Technology, Moscow 125190. Center for Drug Chemistry, All-Russian Scientific Research Institute for Pharmaceutical Chemistry, Moscow 119815. Translated from Khimiya Geterotsklicheskikh Soedinenii, No. 8, pp. 1050–1054, August, 1996. Original article submitted March 20, 1996.     

Synthesis of 3-imino- and 3-oxo-derivatives of pyrano(thiopyrano)[3,4-c]pyridazine

A method has been developed for the synthesis of 3-imino- and 3-oxo-derivatives of pyrano- and thiopyrano[3,4-c]pyridazines from 5-monophenylhydrazones of 2, 2-dimethyltetrahydropyran- and -(thiopyran)-4,5-dione.A. L. Mndzhoyan Institute of Fine Organic Chemistry, National Academy of Sciences of the Republic of Armenia, Erevan, 375014. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1410–1412, October, 1996. Original article submitted December 28, 1995; revision submitted August 6, 1996.     

Electrophilic substitution in benzo[b]thieno[2,3-c]pyridine. Acylation

A study has been made of the acetylation and benzoylation of substituted benzo[b]thieno[2, 3-c]pyridines. It has been shown that acetylaton proceeds exclusively at position 8, whereas benzoylation leads to a mixture of products of substitution at positions 6 and 8. The molecules in question have been calculated in the PPP and MNDO approximations.L. M. Litvinenko Institute of Physical Organic Chemistry and Coal-Tar Chemistry, Academy of Sciences of the Ukraine, Donetsk 340114. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 701–705, May, 1994. Original article submitted March 3, 1994.     

Synthesis of n-(phenoxathiin-2-carbonyl)-or N-(thianthrene-2-carbonyl)-N′-arylthioureas

The reactions of phenoxathiin-2-carbonyl-or thianthrene-2-carbonyl-isothiocyanates with certain primary amines lead to the formation of corresponding N-substituted-N-hetaroylthiocarbamides. The aforementioned isothiocyanates were obtained in situ by reactions of phenoxathiin-2-or thianthrene-2-carbonyl chlorides with KSCN. The new compounds were characterized by elemental analysis and spectral data (IR,¹H and¹³C NMR).Analytical Laboratory-Biofarm, 99 Logofat Tautu Street, Bucharest, Roumania. Faculty of Pharmacy, Organic Chemistry Departament, University of Medicine and Pharmacy Carol Davila, 6 Traian Vuia Street, Bucharest, Roumania, Faculty of Chemistry, Organic Chemistry Department, University of Bucharest, 90–92 Panduri Road, 76233, RoumaniaPublished in Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1681–1686, December, 1999.     

New method for the synthesis of 1,2,3-triazole 1-oxides

A general method is proposed for the synthesis of 1,2,3-triazole 1-oxides using 3,4-dinitro- or 4-amino-3-nitrofuroxanes.Deceased.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913, Moscow. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 675–679, May, 1996. Original article submitted February 22, 1996. Resubmitted after revision April 5, 1996.     

Synthesis of substituted 2-alkyl(aryl)thio-3-cyanopyridines and 3-aminothieno[2,3-b]pyridines

The alkylation of 6-methyl-4-methoxymethyl-3-cyano-2-(1H)pyridinethione by halogen derivatives in the presence of KOH proceeds regioselectively with the formation of S-alkyl derivatives. By cathodic electrolysis of the thiols in the presence of 6-methyl-4-methoxymethyl-2-chloro-3-cyanopyridine, 2-arylthiopyridines are obtained. By Thorpe-Ziegler cyclization of 2-alkylthiopyridines having an ctive methylene group, 2-aminothieno[2,3-b]pyridines have been synthesized.Kuban State Technological University, Krasnodar, 350072. N. D. Zelinskii Institute of Organic Chemistry, Moscow 117913. Southern Branch of Association Rosvuznauka, Krasnodar, 350072. Translated from Khimiya Geterotsiklicheskikh Soedinenii, NO. 10, pp. 1432–1437, October, 1996. Original article submitted April 2, 1996; revision submitted August 20, 1996.     

Synthesis of 1,3-diglycidylimidazolium salts

For the first time, 1,3-diglycidylimidazolium salts were obtained. Their synthesis was accomplished by two routes: the reaction of imidazole with epichlorohydrin in the presence of sodium perchlorate with the subsequent dehydrochlorination of the reaction products with alkalis, and the quaternization of 1-glycidylimidazoles with epichlorohydrin in the presence of salts of strong acids.Institute of Organophysical Chemistry and Carbon Chemistry, National Academy of Sciences of Ukraine, Donetsk 340114. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1062–1066, August, 1996. Original article submitted May 31, 1996.     

Quantum chemical investigation of the effect of cation size on the course of the methylation of 2,4-dioxoquinazoline salts

The effect of cation size on the dual reactivity of the lithium, sodium, and potassium salts of 2, 4-dioxoquinazolines in liquid and solid phase methylation reactions has been studied. The results obtained were confirmed by data of quantum chemical calculations and IR spectroscopy.Institute of Plant Chemistry, Academy of Sciences of the Uzbekistan Republic, Tashkent 700174. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 821–825, June, 1996. Original article submitted August 19, 1993; revision submitted March 19, 1996.     

Reaction of lithioalkoxyallenes with isothio-cyanates: Synthesis of pyrroles and 5,6-dihydropyridines

We have found a novel synthesis route for 2,3-disubstituted pyrroles and 5,6-dihydropyridines, starting from lithiated alkoxyallenes, and organic isothiocyanates.Irkutsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, Irkutsk 664033. Preparative Organic Chemistry Group, Utrecht University, The Netherlands. Translated from Khimya Geterotsiklicheskikh Soedinenii, Vol. 32, No. 7, pp. 917–918, July, 1996. Original article submitted April 17, 1996.     

Synthesis of 3,4-diamino-1H-pyrazolo[3,4-d]pyrimidines

The reaction of 4-(amino-substituted)-2-methylthio-6-chloropyrimidine-5-carbonitriles with hydrazine and methylhydrazine was used to synthesize 3, 4-diamino-6-methylthio-1H-pyrazolo[3, 4-d]pyrimidines. It was shown that the formation of pyrazolopyrimidines proceeds through intermediate 6-hydrazinopyrimidine-5-carbonitriles.Department of Organic Chemistry, Vil'nyus University, Vil'nyus 2006. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 831–836, June, 1996. Original article submitted February 9, 1996.     

Isolation of beet pectin on solid-phase fermentation

Beet pectin has been isolated by the solid phase fermentation method; its physicochemical characteristics are given.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 89 14 75. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 3–6, January–February, 1996. Original article submitted May 29, 1995.     

Synthesis and transformations of 6-amino-3,5-dicyano-4ethylpyridine-2(1H)-thione

The condensation of propionaldehyde with cyanothioacetamide gives 6-amino-3,5-dicyano-4-ethylpyridine-2(1H)-thione, which was used to obtain substituted 2-alkylthiopyridines, 2-ethylthio-6- ethylaminopyridine, and pyrazolo[3,4-b]pyridine.T. G. Shevchenko Lugansk State Pedagogical Institute, 348011 Lugansk. N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Science, 117913 Moscow. Translated from Khimiya Geterotsklicheskikh Soedinenii, No. 8, pp. 1094–1098, August, 1996. Original article submitted March 4, 1996; revision submitted July 1, 1996.     

Stagewise control of the production of allapinin from the herbAconitum leucostomum

An express method has been developed for the analysis of intermediates and wastes in the production of allapinin, using a diffusional equilibrium followed by spectrophotometry.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 89 14 75. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 388–390, May–June, 1996. Original article submitted March 27, 1995.     

Effect of chemical modification of VPO catalysts on their acid-base and catalytic properties in the oxidation ofn-pentane

Controlled modification of the VPO catalyst gives rise to a new route in the partial oxidation of n-pentane leading to citraconic (methylmaleic) anhydride.L. V. Pisarzhevskii Institue of Physical Chemistry, National Academy of Sciences of Ukraine, Prospekt Nauki 31, 252039 Kiev, Ukraine. Institute of Catalysis and Surface Chemistry, Nezapominaek St., Krakow, Poland. Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 32, No. 3, pp. 186–189, May–June, 1996. Original article submitted July 12, 1995.