Oxidative opening of the 2,5-dihydroxy-3,4,6,7-tetrachlorocoumaran ring

A method has been developed for the synthesis of (3,5,6-trichloro-1,4-benzoquinone-2-yl)chloroacetaldehyde by the oxidative ring opening of 2,5-dihydroxy-3,4,6,7-tetrachlorocoumaran with nitrogen oxides. The ion-radical salt of (3,5,6-trichloro-1,4-benzoquinone-2-yl)chloroacetaldehyde with N,N,N,N-tetramethyl-p-phenylenediamine (11) has been synthesized. The reaction of 2,5-dihydroxy-3,4,6,7-tetrachlorocoumaran-3-yl) with pyridine gave N-(2,5-dihydroxy-4,6,7-trichlorocoumaran-3-yl)pyridine chloride, which is also formed from the opening of the coumaran ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 892–895, July, 1990.     

Ring-chain isomerism of imines of N-monosubstituted 2-benzoylbenzenesulfonamides

Imines of N-monosubstituted 2-benzoylbenzenesulfonamides or their ring isomers, viz., 3-amino-3-phenylbenzoisothiazoline 1,1-dioxides, were synthesized by condensation of the dilithium derivatives of N-monosubstituted benzenesulfonamides with benzonitrile. Interconversions of the isomers were realized for the N-phenyl derivative. The introduction of bulky isopropyl or tert-butyl substituents at the sulfonamide nitrogen atoms stabilizes the open structure. The ring isomers of the N-acylimines, viz., 3-acylamino-3-phenylbenzoisothiazoline 1,1-dioxides, are formed exclusively in the acylation of both the open and ring isomers.Communication 6 from the series Ring-Chain Transformations with the Participation of a C=N Group. See [1] for Communication 5.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1209–1213, September, 1981.     

Reaction of isopropylidene malonate with N-arylidene-2-naphthylamines

It is shown that 4-aryl-2-oxo-1,2,3,4-tetrahydro-5,6-benzoquinolines are formed in the reaction of N-arylidene-2-naphthylamines with isopropylidene malonate. The reaction takes place with cleavage of the isopropylidene malonate ring and the production of carbon dioxide and acetone. The structure of the benzotetrahydroquinolines obtained were confirmed by identification of the compound obtained by sulfur dehydrogenation of the product of the reaction of isopropylidene malonate with arylidenenaphthylamine (aryl=phenyl) with an authentic sample of 1,2-dihydro-2-oxo-4-phenyl-5,6-benzoquinoline and of the reaction product (in which the aryl group was absent) with an authentic sample of 2-oxo-1,2,3,4-tetrahydro-5,6-benzoquinoline. The IR and PMR spectra data are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 973–976, July, 1977.     

The composition of commercial acetylated glycerol samples determined by 13C and 1H NMR. The comparison with gas chromatography

A convenient method for the analysis of commercial acetylated glycerol samples based on ¹³C NMR is presented with the accuracy comparable to the standard gas chromatography approaches. The advantage of method is that it does not need any sample derivatization procedure by silyl groups and its application is much more straightforward, as compared to the published ¹H NMR method.     

Synthesis of 2,3-dimethyl-6-methoxycarbonyltetrathiafulvalene

A method is proposed for the synthesis of an unsymmetrically substituted tetrathiafulvalene with an acceptor substituent, viz., 2, 3-dimethyl-6-methoxycarbonyltetrathiafulvalene, from 2-tributylphosphonia-4-methoxycarbonyl-1,3-dithiole tetrafluoroborate.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 476–477, April, 1982.     

Ring-chain isomerization of 2-substituted 3-hydroxy-3-(4-dimethyl-aminophenyl)isoindolinones

N-Unsubstituted and N-monosubstituted amides of 2-(4-dimethylaminobenzoyl)benzole acid exist in the chain form of 3-hydroxyisoindolinones in the crystalline state and in solutions in dioxane, whereas the tautomeric amide hydroxyisoindolinone equilibrium occurs (except for the methyl derivative) in more polar solvents. The analogous N-(1-adamantanyl)amide exists in the open form and does not undergo cyclization under alkaline catalysis conditions; protonation of the dimethylamino group is accompanied in all cases by splitting out of water to give compounds with a quinoid structure; an equilibrium between the protonated and quinoid forms, which is shifted markedly to favor the latter, is observed for some compounds.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 780–785, June, 1979.     

Synthesis of n-alkyl 4,5-dithionaphthalimides

Riga Technical University, Riga LV-1048. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, p. 420, March, 1995. Original Article submitted February 12, 1995.     

Synthesis and properties of N,N′-bis(1,3-indanedion-2-yl)imidazolium betaine

A method for the synthesis of a new type of onium derivative of 1,3-indanedione — N,N-bis(1,3-indanedion-2-yl)imidazolium betaine — by anhydride condensation of N-(1,3-indanedion-2-yl)-N-carboxymethylimidazolium betaine with phthalic anhydride was developed. The new substance is an acid and forms stable salts.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 771–774, June, 1991.     

Synthesis of 4-ethoxycarbonylmethyl-, 4-N-phenylcarbamoylmethyl-, and 4-carboxymethyl-1,3-dithiole-2-thiones and the corresponding 1,3-dithiolium salts

A method for the preparation of 4-ethoxycarbonylmethyl-, 4-N-phenylcarbamoylmethyl-, and 4-carboxymethyl-1,3-dithiole-2-thiones and the corresponding 1,3-dithiolium salts from -bromoacetoacetic ester, -bromoacetoacetanilide, and sodium tertbutyltrithiocarbonate was developed. The compounds were characterized by their IR and PMR spectra.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 180–183, February, 1984.     

Monoesters of tetrathiafulvalene-2,6(7)-dicarboxylic acid and their use in the preparation of tetrathiafulvalenecarboxylic acid

Monoesters of tetrathiafulvalene-2,6(7)-dicarboxylic acid were synthesized. Decarboxylation of these esters with subsequent hydrolysis gave tetrathiafulvalenecarboxylic acid. Pure mono- and diesters of tetrathiafulvalenedicarboxylic acids were isolated but their assignment to the 2,6- and 2,7-series requires further study.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1630–1633, December, 1984.