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Tomas Torroba - One of the best experts on this subject based on the ideXlab platform.
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heterocyclic chemistry of sulfur chlorides fast ways to complex heterocycles
European Journal of Organic Chemistry, 2006Co-Authors: Maria Garciavalverde, Tomas TorrobaAbstract:This microreview highlights the most important advances in the synthetic applications of sulfur Dichloride and Disulfur Dichloride for the preparation of heterocycles. Sulfur chlorides can be considered some of the best sulfur-transfer reagents for the synthesis of heterocyclic systems. Their high reactivity towards nucleophilic organic compounds such as alkenes, alkynes, amines, nitriles, oximes, and their both chlorinating and sulfurating character explain the extensive use of these reagents. In many cases, the initial reactions give rise to reactive intermediates that can be trapped by nucleophiles in a tandem fashion, expanding the possibilities of the reactions. In this way, several new heterocyclic systems can be obtained by a careful selection of the appropriate combination of reagents. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
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selective syntheses of bis 1 2 dithiolo 1 4 thiazines and bis 1 2 dithiolopyrroles from hunig s base
Journal of Organic Chemistry, 1998Co-Authors: Charles W. Rees, Oleg A. Rakitin, Andrew J P White, David J Williams, Carlos F Marcos, C Polo, Tomas TorrobaAbstract:The reaction of N,N-diisopropylethylamine (Hunig's base) and Disulfur Dichloride in 1,2-dichloroethane, in the presence of DABCO, gives 4-ethylbis[1,2]dithiolo[5,4-b][4‘,5‘-e][1,4]thiazine-3,5-dithione (1), or, by addition of oxygen donors, the 3-oxo-5-thione 2 or 3,5-dione 3 derivatives are selectively obtained. When the first reaction is performed in boiling chlorobenzene, 4-ethylbis[1,2]dithiolo[4,5-b][5‘,4‘-d]pyrrole-3,5-dithione (4) is obtained by sulfur extrusion from 1, and in the presence of oxygen donors, the 3-oxo-5-thione 5 or 3,5-dione 6 derivatives are selectively obtained. Some interconversions of compounds 1−6 are described, and a coherent set of reaction pathways for the formation of all six products is proposed. X-ray diffraction shows that the new bis-dithiolothiazine ring system of 1−3 is folded out of planarity about the thiazine N−S vector, with the N-ethyl group folded back over the thiazine ring in a scorpion-like conformation. The new bis-dithiolopyrrole ring system of 4−6 is plana...
Charles W. Rees - One of the best experts on this subject based on the ideXlab platform.
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Unprecedented conversion of triethylamine and Disulfur Dichloride into a thienopentathiepin and a heptathiocane.
Organic letters, 2003Co-Authors: Lidia S. Konstantinova, Oleg A. Rakitin, Charles W. Rees, Ljudmila I. Souvorova, Denis G. Golovanov, Konstantin A. LyssenkoAbstract:In a remarkable cascade reaction, triethylamine is converted into the thienopentathiepin 2a and the heptathiocane 3a by a preequilibrated solution of Disulfur Dichloride and DABCO in chloroform.
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selective syntheses of bis 1 2 dithiolo 1 4 thiazines and bis 1 2 dithiolopyrroles from hunig s base
Journal of Organic Chemistry, 1998Co-Authors: Charles W. Rees, Oleg A. Rakitin, Andrew J P White, David J Williams, Carlos F Marcos, C Polo, Tomas TorrobaAbstract:The reaction of N,N-diisopropylethylamine (Hunig's base) and Disulfur Dichloride in 1,2-dichloroethane, in the presence of DABCO, gives 4-ethylbis[1,2]dithiolo[5,4-b][4‘,5‘-e][1,4]thiazine-3,5-dithione (1), or, by addition of oxygen donors, the 3-oxo-5-thione 2 or 3,5-dione 3 derivatives are selectively obtained. When the first reaction is performed in boiling chlorobenzene, 4-ethylbis[1,2]dithiolo[4,5-b][5‘,4‘-d]pyrrole-3,5-dithione (4) is obtained by sulfur extrusion from 1, and in the presence of oxygen donors, the 3-oxo-5-thione 5 or 3,5-dione 6 derivatives are selectively obtained. Some interconversions of compounds 1−6 are described, and a coherent set of reaction pathways for the formation of all six products is proposed. X-ray diffraction shows that the new bis-dithiolothiazine ring system of 1−3 is folded out of planarity about the thiazine N−S vector, with the N-ethyl group folded back over the thiazine ring in a scorpion-like conformation. The new bis-dithiolopyrrole ring system of 4−6 is plana...
Panayiotis A. Koutentis - One of the best experts on this subject based on the ideXlab platform.
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The Preparation and Characterization of 5-Substituted-4chloro-1,2,3-dithiazolium Salts and their Conversion into 4-
2013Co-Authors: Substituted--chloro- -thiadiazoles, Panayiotis A. KoutentisAbstract:Abstract: A series of monosubstituted acetonitriles were treated with Disulfur Dichloride at room temperature in CH2Cl2 to afford 5-substituted-4-chloro-1,2,3-dithiazolium chlorides 1. Where the 5-substituent was not a good leaving group the chloride salts were converted into the corresponding perchlorate salts 2 which were sufficiently stable and soluble to provide both 1 H- and 13 C-NMR and cyclic voltammetry data. Several of the dithiazolium chlorides were converted into their corresponding 4-substituted-3-chloro-1,2,5-thiadiazoles 13 on treatment with aqueous ammonia. Mechanisms for all reactions are proposed
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The Preparation and Characterization of 5-Substituted-4-chloro-1,2,3-dithiazolium Salts and their Conversion into 4-Substituted-3-chloro-1,2,5-thiadiazoles
MDPI AG, 2005Co-Authors: Panayiotis A. KoutentisAbstract:A series of monosubstituted acetonitriles were treated with Disulfur Dichloride atroom temperature in CH2Cl2 to afford 5-substituted-4-chloro-1,2,3-dithiazolium chlorides 1.Where the 5-substituent was not a good leaving group the chloride salts were converted intothe corresponding perchlorate salts 2 which were sufficiently stable and soluble to provideboth 1H- and 13C-NMR and cyclic voltammetry data. Several of the dithiazolium chlorideswere converted into their corresponding 4-substituted-3-chloro-1,2,5-thiadiazoles 13 ontreatment with aqueous ammonia. Mechanisms for all reactions are proposed
Oleg A. Rakitin - One of the best experts on this subject based on the ideXlab platform.
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Unprecedented conversion of triethylamine and Disulfur Dichloride into a thienopentathiepin and a heptathiocane.
Organic letters, 2003Co-Authors: Lidia S. Konstantinova, Oleg A. Rakitin, Charles W. Rees, Ljudmila I. Souvorova, Denis G. Golovanov, Konstantin A. LyssenkoAbstract:In a remarkable cascade reaction, triethylamine is converted into the thienopentathiepin 2a and the heptathiocane 3a by a preequilibrated solution of Disulfur Dichloride and DABCO in chloroform.
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selective syntheses of bis 1 2 dithiolo 1 4 thiazines and bis 1 2 dithiolopyrroles from hunig s base
Journal of Organic Chemistry, 1998Co-Authors: Charles W. Rees, Oleg A. Rakitin, Andrew J P White, David J Williams, Carlos F Marcos, C Polo, Tomas TorrobaAbstract:The reaction of N,N-diisopropylethylamine (Hunig's base) and Disulfur Dichloride in 1,2-dichloroethane, in the presence of DABCO, gives 4-ethylbis[1,2]dithiolo[5,4-b][4‘,5‘-e][1,4]thiazine-3,5-dithione (1), or, by addition of oxygen donors, the 3-oxo-5-thione 2 or 3,5-dione 3 derivatives are selectively obtained. When the first reaction is performed in boiling chlorobenzene, 4-ethylbis[1,2]dithiolo[4,5-b][5‘,4‘-d]pyrrole-3,5-dithione (4) is obtained by sulfur extrusion from 1, and in the presence of oxygen donors, the 3-oxo-5-thione 5 or 3,5-dione 6 derivatives are selectively obtained. Some interconversions of compounds 1−6 are described, and a coherent set of reaction pathways for the formation of all six products is proposed. X-ray diffraction shows that the new bis-dithiolothiazine ring system of 1−3 is folded out of planarity about the thiazine N−S vector, with the N-ethyl group folded back over the thiazine ring in a scorpion-like conformation. The new bis-dithiolopyrrole ring system of 4−6 is plana...
Akihiko Ishii - One of the best experts on this subject based on the ideXlab platform.
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practical synthesis of thiirene 1 oxides that possess two bulky alkyl substituents
Heteroatom Chemistry, 2002Co-Authors: Juzo Nakayama, Michiyo Morita, Yoshiaki Sugihara, Kenta Takahashi, Akihiko IshiiAbstract:Acetylenes that possess two bulky alkyl substituents reacted with sulfur Dichloride to furnish the corresponding 2,3-dialkyl-2,3-dichlorothiiranes (5) nearly quantitatively. The alkaline hydrolysis of 5 afforded 2,3-dialkylthiirene 1-oxides (10) in high yields. These two reactions could be successively carried out in one flask, and 2,3-di-tert-butyl-, 2,3-di-(1-adamantyl)-, and 2-(1-adamantyl)-3-tert-butylthiirene 1-oxides (10a–c) were obtained in 70, 80, and 90% yields, respectively, based on the starting acetylenes, thus providing the most convenient synthesis of thiirene 1-oxides. Disulfur Dichloride also reacted with acetylenes to give 5 in good yields with the elimination of one sulfur atom. Although the alkaline hydrolysis of 5 provided 10 exclusively, acid hydrolysis gave a mixture of α-oxothioketone 9 and thiirene 1-oxide 10 in modest yields. All thiirene 1-oxides 10a–c isomerized to produce α-oxothioketones 9 in high yields when heated in boiling toluene. Reactions of a bis-acetylene (18) with Disulfur Dichloride and with sulfur Dichloride gave a dihydropentathiepin (19) in high yields. © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:424–430, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/hc.10070
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synthesis structure and some reactions of 2 4 6 tri t butyl thiobenzaldehyde the first stable aromatic thioaldehyde
Bulletin of the Chemical Society of Japan, 1996Co-Authors: Akihiko Ishii, Naoko Kumon, Fujiko Iwasaki, Naoki Inamoto, Nobuo Fukuda, Hiroyuki Oyama, Takashi Ishida, Renji OkazakiAbstract:The title compound 1 was synthesized by the reaction of 2,4,6-tri-t-butylphenyllithium with O-ethyl thioformate or that of 2,4,6-tri-t-butylbenzaldehyde hydrazone with Disulfur Dichloride in the presence of triethylamine. The thioaldehyde 1 is a purple crystalline compound which is thermally quite stable; only around 200 °C it underwent intramolecular cyclization to give 6,8-di-t-butyl-3,4-dihydro-4,4-dimethyl-1H-2-benzothiopyran 9. The X-ray crystallographic analysis of 1 revealed that the thioformyl group is almost perpendicular to the aromatic ring. The reaction of 1 with 1-cyano-1-methylethyl radicals afforded 9, while that with t-butyl radicals gave 1,3,5-tri-t-butyl-2-t-butylthiomethylbenzene and t-butyl 2,2-dimethyl-1-(1,3,5-tri-t-butylbicyclo[2.2.0]hexa-2,5-dien-2-yl)propyl sulfide in addition to 9. Some Grignard reagents and organolithiums reacted with 1 gave carbophilic, thiophilic, double addition products and some others depending on the kind of the organometallic reagents. Hydrazine and butyl...