- 3,5-Dihydro-2H-thieno[2,3-c]pyrrole 1,1-dioxide - A new simple pyrrole unit. Preliminary communication
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2,3-Dihydrothiophene 1,1-dioxide ('2-sulfolene') reacted with tosylmethyl isocyanide (TsMIC) in the presence of a base to give the hitherto unknown 3,5-dihydro-2H-thieno[2,3-c]pyrrole 1,1-dioxide ('β′- sulfolenopyrrole') from the expected cyclocondensation. A serendipitous formation of this β′-sulfolenopyrrole was found earlier, when we investigated synthetic routes to a 3,5-dihydro-1H-thieno[ 3,4-c]pyrrole 2,2-dioxide (a 'β″-sulfolenopyrrole') from TsMIC and 2,5-dihydrothiophene 1,1-dioxide ('3-sulfolene'). Here, we present the synthesis and characterization of β′-sulfolenopyrrole. The X-ray crystal-structure analyses of β′-sulfolenopyrrole and the isomeric β″-sulfolenopyrrole are also reported here. This β′- sulfolenopyrrole is a new type of a functionalized pyrrole, which is likely to be of interest for pharmaceutical purposes.
- Banala, Srinivas,Wurst, Klaus,Kraeutler, Bernhard
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- Rhodium-catalyzed asymmetric arylation of allyl sulfones under the conditions of isomerization into alkenyl sulfones
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The reaction of 3-sulfolene with arylboronic acids in the presence of a chiral diene-rhodium catalyst under highly basic conditions (10 equiv of KOH) gave high yields of 3-arylsulfolanes with high enantioselectivity, where 3-sulfolene is in equilibration
- Lim, Kelvin Meng-Hui,Hayashi, Tamio
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supporting information
p. 3201 - 3204
(2015/03/30)
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- PYRIDAZINONE COMPOUNDS
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The invention is directed to pyridazinone compounds and pharmaceutical compositions containing such compounds that are useful in treating infections by hepatitis C virus.
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Page/Page column 162-163
(2008/12/07)
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- Double bond migration in S-allyl systems catalysed by [RuC1H(CO)(PPh3)3]
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Reactions of S-allyl systems (allyl sulphides of R-S-allyl type, where R = Et, allyl, Ph, Me3C, Ph3C, as well as of allyl phenyl sulphoxide, allyl phenyl sulphone, 2,5-dihydro-1,1-dioxothiophene) with [RuClH(CO) (PPh3)sub
- Ku?nik, Nikodem,Krompiec, Stanis?aw,Bieg, Tadeusz,Baj, Stefan,Skutil, Krzysztof,Chrobok, Anna
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p. 167 - 175
(2007/10/03)
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- Regiochemical and Stereochemical Studies on Halocyclization Reactions of Unsaturated Sulfides
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The regiochemistry and stereochemistry for the halocyclization reactions of unsaturated benzyl sulfides have been examined as a function of tether length, type of unsaturation (carbon-carbon double bond versus carbon-carbon triple bond), substituents, and halogenating agent.Alkenyl sulfides were found to react with iodine or bromine at room temperature to give five-membered ring cycloadducts exclusively over those having four-membered rings, while for larger systems, six-membered ring products are formed preferentially over their five-membered ring isomers and exclusively over the seven-membered ring adducts.The endo- versus exo-regioselectivity of these alkenyl sulfide ring closure most likely reflects the difference in thermodynamic stabilities of the β-halo sulfide cycloadducts, which are able to equilibrate via a common episulfonium intermediate.The efficiency of cyclization process markedly drops off for these alkenyl sulfides as the tether length increases beyond four intervening carbon centers.Thus, while the halogenations of 3-butenyl sulfides and 4-pentenyl sulfides give high yields of cycloadducts, those of 5-hexenyl sulfides afford only small amounts of cyclized products and large quantities of acyclic dibromides.Conversely, the reactions of acetylenic sulfides with iodine give uniformly high yields and regiochemical control regardless of the tether length.Thus, 3-butynyl and 4-pentynyl sulfides cyclize cleanly to the five-membered ring while 5-hexynyl sulfides give exclusively the six-membered ring.The products arising from these alkynyl sulfide ring closures are believed to be formed under kinetic control.The methodology has been applied to the synthesis of unusual bicyclic β-lactams related to the penicillin family of antibiotics.
- Ren, Xiao-Feng,Turos, Edward,Lake, Charles H.,Churchill, Melvyn Rowen
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p. 6468 - 6483
(2007/10/03)
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- SENSITIZED PHOTOCYCLODIMERIZATION OF α,β-UNSATURATED CYCLIC SULFONES. CRYSTAL STRUCTURAL ANALYSES OF THE PHOTODIMERS OF 2-SULFOLENE AND THIA-2-CYCLOHEXENE-1,1-DIOXIDE
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The reactivity of five- and six-membered unsaturated cyclic sulfones in sensitized photocyclodimerization depends on position and substitution of the double bond.Thus, 2-sulfolene (1) and its six-membered analogue thia-2-cyclohexene-1,1-dioxide (3) photodimerize to yield each three products, 5, 6, 7 and 9, 10, 11, respectively, of which only 7 and 10 are analogous.However, 3-methyl-2-sulfolene (1a), 3-sulfolene (2) and its 3-methyl derivative (2a), as well as thia-3-cyclohexene-1,1-dioxide (4) remain unchanged under the same conditions.Dimerization of 1 and 3 is also effected by γ-irradiation.Structure and stereochemistry of the six dimers were determined by crystal structural analyses.Except for 6, the main product of γ-radiation-induced dimerization of 1, all the other dimers (5, 7 and 9-11) are tricyclic cycloadducts with anti (transoid) configuration at the central cyclobutane ring. 6 is an unsaturated open-chain dimer with C-C and C-S bond contractions, the latter indicating conjugation of the double bond with the sulfone group.While the cyclobutane rings of 5 and 7 (from 1) are planar, those of all three dimers from 3 are folded: the 6.4.6 skeletons of two of them comprise one (11) or two (9) trans fusions.
- Kuhn, Hans Jochen,Defoin, Rosalie,Gollnick, Klaus,Krueger, Carl,Tsay, Yi-Hung,et al.
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p. 1667 - 1678
(2007/10/02)
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- A Study of 2-Methyl-3-phenylsulphinyl-2,3,4,5-tetrahydrothiophene 1,1-Dioxides: NMR Spectra, Crystal Structure and Dehydrosulphinylations
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The (2R*,3S*,SR*) and (2R*,3S*,SS*) isomers of 2-methyl-3-phenylsulphinyl-2,3,4,5-tetrahydrothiophene 1,1-dioxide were converted to 2-methyl-4,5-dihydrothiophene 1,1-dioxide in refluxing toluene, while the (2S*,3S*,SR*) isomer underwent thermolysis to give 2-methyl-2,5-dihydrothiophene 1,1-dioxide.No reaction of the (2S*,3S*,SS*) isomer occurred because the required conformation in dehydrosulphinylation was prohibited by the steric effect of the methyl and phenyl groups.
- Fang, Jim-Min,Lin, Jin-Ruen,Duh, Jing-Min,Cheng, Ming-Chu,Wang, Yu
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p. 2136 - 2149
(2007/10/02)
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- 4-Bromo-2-sulfolenes. Butadienyl Cation Equivalents
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4-Bromo-2-sulfolene and 4-bromo-3-methyl-2-sulfolene react with alkylcuprates to give direct substitution products, with vinyl- or phenylcuprates or sulfur-containing nucleophiles to give allylic substitution products, and with strongly basic nucleophiles to give elimination products.The allylic substitution products and the isomerized direct substitution products are precursors for substituted 1,3-butadienes.Thus, these 4-bromo-2-sulfolenes serve as butadienyl cation equivalents.
- Chou, Ta-shue,Hung, Su Chun,Tso, Hsi-Hwa
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p. 3394 - 3399
(2007/10/02)
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- CHEMOSELECTIVE REACTIONS OF ULTRASONICALLY DISPERSED POTASSIUM WITH SOME BROMINATED HYDROTHIOPHENE S,S-DIOXIDES
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The reactions of ultrasonically dispersed potassium (UDP) with 4-bromo-2-sulfolenes resulted in chemoselective deprotonation at the C-5 position leading to the elimination-dimerization products.The possible C-S bond and C-Br cleavage reactions were not detected.The reaction of UDP with 3,4-dibromosulfolane resulted in dehydrobromination and double dehydrobromination.
- Chou, Ta-shue,Chen, Mei-Man
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p. 2829 - 2834
(2007/10/02)
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- Study of the Alkylation Reactions of Sulphol-3-enes
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Sulphol-3-ene can be deprotonated with sodium hydride in DMF to form the α-anion which reacts with various alkyl halides to give the 2-alkylsulpholenes.This approach provides a regiospecific preparation of disubstituted sulphol-3-enes and sulphol-2-enes.
- Chou, Ta-shue,Tso, Hsi-Hua,Chang, Lee-Jean
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p. 515 - 520
(2007/10/02)
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- Reaction of sulfolene with β-γ-δ-e{open}-octafluoropentanol
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The reaction of 3-sulfolene with ss-γ-δ-e{open}-octafluoropentanol in an alkaline medium at 90-100 °C was studied. It is shown that the reaction proceeds through isomerization of 3-sulfolene to 2-sulfolene with subsequent addition of the fluorinated alcohol. The reversibility of the last step of the reaction was proved by gas-liquid chromatography.
- Mukhamedova,Kursheva,Nechaeva
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p. 360 - 361
(2007/10/02)
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- HYDROLYSIS OF CARBAMATES AND CARBONATES OF 3-HYDROXYTHIOLANE 1,1-DIOXIDE
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Alkylcarbamates of 3-hydroxy-thiolane 1,1-dioxide are hydrolyzed in the presence of bases to give alkyl(1,1-dioxo-3-thiolanyl)amines and 2-thiolene 1,1-dioxide (I).Aryl esters undergo hydrolysis to give sulfone I and 3-hydroxythiolane 1,1-dioxide (II).The corresponding alkyl- and arylcarbonates also form sulfone I and a very small amount of hydroxy derivative II under these conditions.
- Parkhomenko, P. I.,Rybakova, M. V.,Bezmenova, T. E.,Zaika, T. D.
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p. 1122 - 1124
(2007/10/02)
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