Results 241 to 250 of about 51,140 (296)
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The Journal of Organic Chemistry, 1986
Annelation de R-3 thiophenecarbaldehyde-2, -carboxylate-2 de methyle et -carbonitrile-2 et de R-4 thiophenecarboxylate-3 de methyle et -carbonitrile-3 avec des accepteurs de Michael: obtention de benzo [b] thiophenes disubstitues-5,6 et de leurs derives amino ou hydroxy-7 et d'amino- ou hydroxy-4 benzo [c] thiophenes disubstitues-5 ...
TERPSTRA, JW, van Leusen, A.M.
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Annelation de R-3 thiophenecarbaldehyde-2, -carboxylate-2 de methyle et -carbonitrile-2 et de R-4 thiophenecarboxylate-3 de methyle et -carbonitrile-3 avec des accepteurs de Michael: obtention de benzo [b] thiophenes disubstitues-5,6 et de leurs derives amino ou hydroxy-7 et d'amino- ou hydroxy-4 benzo [c] thiophenes disubstitues-5 ...
TERPSTRA, JW, van Leusen, A.M.
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Electrophilic phenylselenenylation of thiophenes. Synthesis of poly(phenylseleno)thiophenes.
Tetrahedron, 1994Abstract The phenylselenenyl sulfate, generated from the oxidation of diphenyl diselenide with ammonium persulfate, easily effects electrophilic aromatic substitution reactions on thiophene, 2- and 3-methylthiophenes and on 3-bromothiophene. The phenylseleno group activates the substrate to further substitution.
TIECCO, Marcello +4 more
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Journal of the Chemical Society B: Physical Organic, 1970
A study of salt effects and activation parameters indicates that the mechanism of bromination of thiophen in aqueous acetic acid is the same as that of benzene compounds. There is an isotope effect (kH/kD) of 1·3, which is shown to be secondary and does not represent slow proton loss.
Anthony R. Butler, James B. Hendry
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A study of salt effects and activation parameters indicates that the mechanism of bromination of thiophen in aqueous acetic acid is the same as that of benzene compounds. There is an isotope effect (kH/kD) of 1·3, which is shown to be secondary and does not represent slow proton loss.
Anthony R. Butler, James B. Hendry
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2000
Abstract Thiophene can be found in peat, coal tar and gas, and technical grades of benzene. It has similar physical properties to benzene and may be used as a solvent. Thiophene is used to manufacture resins with phenol and formaldehyde, dyes, and pharmaceuticals, including dopamine-uptake antagonists and anticonvulsants.
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Abstract Thiophene can be found in peat, coal tar and gas, and technical grades of benzene. It has similar physical properties to benzene and may be used as a solvent. Thiophene is used to manufacture resins with phenol and formaldehyde, dyes, and pharmaceuticals, including dopamine-uptake antagonists and anticonvulsants.
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Electronic spectrum of thiophen and some deuterated thiophens
Journal of the Chemical Society, Faraday Transactions 2, 1972The electronic absorption spectra of thiophen and of some deuterated thiophens have been studied in the range 2500–1400 A. Three electronic transitions, with origins at 41 595, 48 330 and 53 270 cm–1 in C4H4S and two Rydberg series leading to the limit 71 570 cm–1 were analyzed.
G. Di Lonardo +3 more
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Radiation-Driven Destruction of Thiophene and Methyl-Substituted Thiophenes
AstrobiologyThiophene and two derivatives (2-methylthiophene and 3-methylthiophene) have been detected on the surface of Mars with the Sample Analysis at Mars instrument suite onboard NASA’s Curiosity rover. Thiophene could serve as a secondary chemical biosignature since the secondary biosynthesis of thiophene is considered an important production pathway ...
Patrick D. Tribbett +4 more
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Condensations of Thiophene with Ketones.
ChemInform, 2002AbstractFor Abstract see ChemInform Abstract in Full Text.
Brian J. Morrison, Oliver C. Musgrave
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9.10.4 Thiophenes, Thiophene 1,1-Dioxides, and Thiophene 1-Oxides (Update 2011)
2011Abstract This manuscript is an update to the earlier Science of Synthesis contribution describing methods for the synthesis of thiophenes. The main focus lies on modern synthetic transformations, such as transition-metal-mediated coupling reactions, leading to functionalized thiophenes.
J. Schatz, M. Seßler
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Organic Letters, 2013
Three convergent routes to thiophenes are described, hinging on the radical addition of α-xanthyl ketones to ethyl vinyl sulfide or to vinyl pivalate. The latter route ultimately proved to be the most versatile and efficient (61-94%).
Jullien, Hélène +3 more
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Three convergent routes to thiophenes are described, hinging on the radical addition of α-xanthyl ketones to ethyl vinyl sulfide or to vinyl pivalate. The latter route ultimately proved to be the most versatile and efficient (61-94%).
Jullien, Hélène +3 more
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Kinetics of the desulfurization of thiophene: Reactions of thiophene and butene
Journal of Catalysis, 1977Abstract The kinetics of the desulfurization of thiophene on a representative CoOMoO 3 Al 2 O 3 were studied in the temperature range of 250–313 °C for partial pressures of thiophene from 20 to 160 Torr and for partial pressures of hydrogen from 550–750 Torr.
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