Researches on 2,1,3-thia-and selenadiazoles

Chloromethylation of 4- and 5-chlorobenzo-2,1,3-thiadiazoles with dichlorodimethyl ether in the presence of anhydrous aluminum chloride gives 4-chloro-7-chloromethyl- and 5-chloro-4-chloromethylbenzo-2, 1,3-thiadiazoles respectively. Reductive scission followed by treatment with thionyl chloride converts them to 4-chloro-7-methyl- and 5-chloro-4-methylbenzo-2,1,3-thiadiazoles; Chlorination of the latter gives 4-methyl-5,7-dichlorobenzo-2,1,3-thiadiazole. Replacement of the chlorine in the chloromethyl groups gives 4-chloro-7-hydrosymethyl-,5-chloro-4-hydroxymethyl-, 4-chloro-7-cyanomethyl-,4-chloro-7-carboxymethyl-,5-chloro-4-carboxymethylbenzo-2,1,3-thiadiazoles. Reductive scission of 4-chlorobenzo-2,1,3-thidiazole followed by treatment with sodium selenite gives 4-chlorobenzo-2,1,3-selenadiazole.Part XLIII see [1].     

Investigations on 2, 1, 3-thia- and selenadiazoles

Nitration and nitrosation of 4-hydroxy-5-methyl-benzo-2, 1, 3-thiadiazole gives 4-hydroxy-5-methyl-7-nitro-and 4-hydroxy-5-methyl-7-nitrosobenzo-2, 1, 3-thiadiazoles. Oxidation of the latter, or of 4,7-diamino-5-methylbenzo-2,1,3-thiadiazole gives 5-methyl-4,7-dihydroxy-2, 1, 3-thiadiazole, forming derivatives with sodium bisulfite or hydroxylamine, and reduced by sodium dithionite to 5-methyl-4, 7-dihydroxybenzo-2, 1, 3-thiadiazole. The latter is also obtained by diazotizing 5-methyl-4-hydroxy-7-aminobenzo-2, 1, 3-thiadiazole, and decomposing the diazonium salt. Nitration of 4-ethoxybenzo-2, 1, 3-thiadiazole with sodium ethoxide gives 4-ethoxy-7-aminobenzo-2, 1, 3-thiadiazole, acetylated to 4-ethoxy-7-acetaminobenzo-2, 1, 3-thiadiazole.For Part XXXVII see [1].     

Investigations of 2,1,3-thia- and selenadiazoles

All three possible isomeric amines are obtained by the reaction of 4- or 5-methylbenzo-2,1,3-thiadiazoles with hydroxylamine sulfate in concentrated sulfuric acid. Under similar conditions, 5,6-dimethyl-4-aminobenzo-2,1,3-thiadiazole is obtained from 5,6-dimethylbenzo-2,1,3-thiadiazole.See [1] for communication LXIV.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 601–602, May, 1971.     

Studies in the field of 2,1,3-thia- and selenadiazoles

The reaction of benzo-2,1,3-thiadiazole with hydroxylamine sulfate in concentrated sulfuric acid at 150° C for 1–10 hr has been studied. It has been shown that under these conditions mixtures of different amounts of 4- and 5-aminobenzo-2,1,3-thiadiazoles are formed.For part LII, see [1].     

Fries reaction and dakin rearrangement in benzo-2,1,3-thiadiazoles

The Fries rearrangement of 4- and 5-acetoxybenzo-2,1,3-thiadiazoles has given 4-hydroxy-7-acetyl- and 5-hydroxy-4-acetylbenzo-2,1,3-thiadiazoles, which on oxidation afford mixtures of 5-chloro-4,7-dioxo- and 5,6-dichloro-4,7-dioxobenzo-2,1,3-thiadiazole and of 6-chloro-4,5-dioxo- and 6,7-dichloro-4,5-dioxobenzo-2,1,3-thiadiazole. Reaction of 6,7-dichloro-4,5-dioxobenzo-2,1,3-thiadizole with ortho-phenyl-enediamine gives 4,5-dichloro-2,1,3-thiadiazolo[4,5-a]phenazine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1683–1687, December, 1987.     

Conversion of 4-substituted benzo-2,1,3-thiadiazoles to 5-chloro-4,7-dioxobenzo-2,1,3-thiadiazole by action of hydrogen peroxide and hydrochloric acid

Under the influence of hydrogen peroxide and hydrochloric acid in acetonitrile 4-substituted benzo-2,1,3-thiadiazoles form 5-chloro-4,7-dioxobenzo-2,1,3-thiadiazole. 4-Alkoxy- and 4-[(alkoxycarbonyl)methoxy]benzo-2,1,3-thiadiazoles give, in addition, the corresponding 5,7-dichloro derivatives.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 114–117, January, 1988.     

Oxidation and reduction of some derivatives of benzo-2,1,3-thiadiazole

In the reduction of 4-hydroxy-7-phenylazobenzo-2,1,3-thiadiazole and of 4-hydroxy-7-nitro-benzo-2,1, 3-thiadiazole with sodium hydrosulfite, 7-amino-4-hydroxybenzo-2,1,3-thiadiazole is obtained. The reduction of 4-hydroxybenzo-2,1,3-thiadiazole leads to 2,3-diaminophenol which forms 5-hydroxyquinoxaline with the bisulfite derivative of glyoxal. The oxidation of 4-hydroxy- and 4-aminobenzo-2,1,3-thiadiazoles with potassium dichromate in an acid medium has yielded 4,7-dioxo-4,7-dihydrobenzo-2,1,3-thiadiazole, which has been converted into 4,7-dihydroxybenzo-2,1,3-thiadiazole and 4,7-di(hydroxyimino)-4,7-dihydrobenzo-2,1,3-thiadiazole.Translated from Khimiya Geterotsikliches-kikh Soedinenii, No. 7, pp. 926–929, July, 1973.     

Reactions of diazaphospholes with phenyldiazomethane

Conclusions The action of 2-acetyl-5-methyl-1, 2, 3-diazaphosphole on phenyldiazomethane at –15°C in hexane leads to 2-acetyl-4-methyl-8-phenyl-1-phospha-2,3,7,8-tetraazabicyclo[3.3.0]octa-3,7-diene. The inverse action of phenyldiazomethane on 2-acetyl-5-methyl-1,2, 3-diazaphosphole at 0°C in ether gives 4, 11-diacetyl-6,7-dimethyl-2-phenyl-4,5,10,11-tetraaza-1,3-diphosphatricyclo[6.3.0.0^3,7]undeca-5, 9-diene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 412–418, February, 1986.     

Synthesis and study of 4-aminopyrazolones (5)

Some 4-N-thioureido- and -ureido derivatives are synthesized by reacting 1-phenyl-3-methyl-4-aminopyrazolone(5) hydrochloride at 40–50°, in alcohol solution, with potassium thiocyanate in the presence of sodium acetate plus carbon disulfide, phenylisothiocyanate, and hexamethylenediisocyanate. Acetylation of 1-phenyl-3-methyl-4-aminopyrazolone(5) with C₁–C₈ aliphatic carboxylic acids takes place under more drastic conditions at 100–150°, to give the corresponding 1-phenyl-3-methyl-4-acylaminopyrazolones(5), isolated in 40–60% yield. The UV spectra of the compounds studied are investigated.For Part I, see [1].     

2-methyl-3-ethoxycarbonyl-4-hydroxythiophene in the vilsmeier reaction

Continuing our investigation of the properties of 2-methyl-3-ethoxycarbonyl-4-hydroxythiophene (I) [1], we found that it readily undergoes electrophilic substitution reactions. We studied the behavior of I under the conditions of the Vilsmeier reaction. The structures of the reaction products depend on the temperature conditions: at 30–35°C, 2-methyl-3-ethoxycarbonyl-4-hydroxy-5-formylthiophene (H) is formed in 74% yield while 2-methyl-3-ethoxycarbonyl-4-chloro-5-formylthiophene (III) is formed in 50% yield at 100°. The reaction of I with dimethylbenzamide and phosphorus oxychloride gives 2-methyl-3-ethoxycarbonyl-4-hydroxy-5-benzoylthiophene (IV) in 41% yield.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, p. 427, March, 1972.     

Reaction of 1-bromo-2-acylacetylenes with thiobenzhydrazide

Conclusions The reactions of 1-bromo-2-acylacetylenes with thiobenzhydrazide at from –10 to –30°C in ether, acetonitrile, methanol without catalyst, or methanol in the presence of triethylamine gave 2-acylmethyl-5-phenyl-1,3,4-thiadiazoles and their hydrobromide salts.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2637–2638, November, 1988.     

Oxidation of halohydroxybenzo-2,1,3-thiadiazoles with nitric acid

4,5-Dioxobenzo-2,1,3-thiadiazole has been synthesized. Its structure was proven by conversion to the known 4,5-dioximinobenzo-2,1,3-thiadiazole and to 2,1,3-thiadiazolo[4,5-a]phenazine, and by reduction to 4,5-dihydroxybenzo-2,1,3-thiadiazole. Oxidation of 5,6-dichloro-4,7-dihydroxy- and 5,7-dichloro-4-hydroxy-benzo-2,1,3-thiadiazoles forms 5,6-dichloro-4,7-dihydroxybenzo-2,1,3-thiadiazole, of known structure, and 7-chloro-4,5-dioxobenzo-2,1,3-thiadiazole; the latter by reaction with ortho-phenylene diamine is converted to 4-chloro-2,1,3-thiadiazolo[4,5-a]phenazine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 850–852, June, 1987.     

Reaction of hexafluoropropylene and its oligomers with acetone oxime

Reactions of perfluoropropylene and its oligomers with acetone oxime in the presence of a base afford perfluoroalkyl and/or perfluoroalkenyl ethers of acetone oxime. When heated to 100 °C, the 3-perfluoro-2-methyl-2-pentenyl ether of acetone oxime (3) is quantitatively converted to 4-hydroxy-3-methyl-5,5-bistrifluoromethyl-4-pentafluoroethyl-1-pyrroline (4), the structure of which was established by X-ray diffraction analysis. A convenient one-stage synthesis of perfluoro-3-isopropyl-4-methyl-3-penten-2-one (7) was proposed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1068–1072, June, 1994.     

Derivatives of azaindoles. 65. Synthesis of 1-benzyl-4-methyl-5-cyano-6-hydroxy-7-azaindoline

Treatment of the ammonium (I) or benzylammonium salt of 2,6-dihydroxy-3-(-hydroxyethyl)-4-methyl-5-cyanopyridine (II) with a mixture of benzylamine and phosphorus pentoxide yielded 2-benzylamino-3-(-hydroxyethyl)-4-methyl-5-cyano-6-hydroxypyri-dine (III), which, when heated with phosphorus oxychloride, is converted to 1-benzyl-4-methyl-5-cyano-6-hydroxy-7-azaindoline (IV). The products of thermal fragmentation of II with benzylamine were studied by the method of chromato-mass spectrometry. In addition to compound III, N,N-dibenzylurea (V) and the dibenzylamide of malonic acid (VI) were preparatively isolated from the reaction products. The cyclization of I and II to 4-methyl-6-hydroxy-2,3-dihydro-7-azabenzofuran (VII) and 4-methyl-5-cyano-6-hydroxy-2,3-dihydro-7-azabenzofuran (VIII) was carried out. Heating VIII with benzylamine at 200–210°C led to compound III.For communication 64, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1105–1109, August, 1984.     

Synthesis of heterocyclic compounds from the products of addition of polyhaloalkanes to unsaturated systems 4. Synthesis of substituted furo[2,3-d]pyrimidines

2-Amino-5-methyl-4-(2,2,2-trichloroethyl)-3-furonitrile was synthesized from 3,5,5,5-tetrachloropentan-2-one, a product of the radical addition of CCl₄ to methyl vinyl ketone, according to a scheme known for -haloketones. The product was converted via the corresponding imino-ether into N²-substituted N¹ [5-methyl-4-(2,2,2-trichloroethyl)-3-cyano-2-furyl]formamidines. Cyclization of these formamidines gave 2-methyl-3-(2,2,2-trichloroethyl)-5-R-4-imino-4,5-dihydrofuro[2,3-d]pyrimidines, which readily regroup according to Dimroth into 2-methyl-3-(2,2,2-trichloroethyl)-4-R-aminofuro[2,3-d]pyrimidines.For communication 3, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 124–129, January, 1993.     

Synthesis of pyrido[1,2-c][1,3]benzoxazines based on 1-benzyl-3-hydroxy-3-methyl-6-(2-benzyloxyphenyl)-4-piperidones

The stereomeric 1-benzyl-3-hydroxy-3-methyl-6e-(2-bemyloxyphenyl)-4-piperidones on debenzylation and subsequent reaction with formaldehyde are converted into cis- and trans-1,3,4-10b-tetrahydro-3-hydroxy-3-methyl-2-oxopyrido-[1,2-c][1,3]benzoxazines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 124–127, January, 1991.     

Pyrroles from ketoximes and acetylene. 30. The synthesis of 3-alkyl-2-arylpyrroles

Conditions were found for the synthesis of 3-alkyl-2-arylpyrroles using the Trofimov reaction at 50–70 °C both at elevated and atmospheric pressure. O-Vinyloximes and 3H-5-hydroxy-4,5-dihydropyrroles were isolated as intermediates.Communication 29, see ref. [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1501–1505, November, 1985.     

Synthesis of 3-aryl-5-methylpyrrolidino[1,2 b]pyrazoles

The sequential conversion of 5-hydroxy-5-methyl-4-oxo-3-arylpyrrolidino [1,2-b]pyrazoles to 5-methyl-5-chloro4-oxo-, 4-hydroxy-5-methyl-5-chloro-, and 5-methyl-4-oxo-3-arylpyrrolidino[1,2-b]pyrazoles and the HuangMinlon reduction of the last afforded 3-aryl-5-methylpyrrolidino[1,2-b]pyrazoles.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 49–51, January, 1994.     

1,3-Dipolar cycloaddition of diazomethane and diazocyclopropane to 2-fluoro-3-methylbutadiene and thermal transformations of fluorine-containing vinylpyrazolines and vinylcyclopropanes

Reactions of 2-fluoro-3-methylbuta-1,3-diene with diazomethane in ether at 15 °C and with diazocyclopropane generated in situ by decomposition of N-cyclopropyl-N-nitrosourea in the presence of K₂CO₃ in CH₂Cl₂ at –10 °C selectively involve the double bond at the methyl group to give 3-(1-fluorovinyl)-3-methylpyrazolines. Thermal dediazotization of the latter at 250 °C yields 1-(1-fluorovinyl)-1-methylcyclopropane and -spiropentane 5, which are capable of isomerizing, under more severe conditions (400—600 °C), into 1-fluoro-2-methylcyclopent-1-ene and 5-fluoro-4-methylspiro[2.4]hept-4-ene (7), respectively. Spiropentane derivative 5 partially isomerizes into 1-fluoro-2-methyl-3-methylidenecyclohex-1-ene. In a similar way, thermolysis of 6-(2,3,3-trifluorocyclobut-1-enyl)-4,5-diazaspiro[2.4]hept-4-ene at 400 °C gives a mixture of 1-(spiropentyl)-2,3,3-trifluorocyclobut-1-ene and 2,3,3-trifluoro-1-(2-methylidenecyclobutyl)cyclobut-1-ene. Thermolysis of 1-cyclopropyl-2,3,3-trifluorocyclobut-1-ene at 550—620 °C affords a mixture of 1-(trifluorovinyl)cyclopentene and 2,3-difluorotoluene.     

Alkaloids ofHaplophyllum foliosum. III. Structure of folidine

The new alkaloid folidine with mp 148–149°C (acetone-petroleum ether) has been isolated from the epigeal part of the plantHaplophyllum foliosum Vved., and on the basis of spectral characteristics and passage to the known alkaloid folifidine (8-hydroxy-4-methoxy-1-methyl-2-quinoline) its structure has been established as 4-methoxy-1-methyl-8-(2-oxo-3-methylbutoxy)-2-quinolone.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 823–824, November–December, 1985.