- Ethynyl sulfides as participants in cascade cycloaromatizations
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Isomerization of soluble precursor compounds to produce fused-ring systems is an attractive approach for preparing conjugated polymers and oligomers. Cycloaromatization chemistry has previously been explored in this capacity employing reactions based on the Bergman cyclization. Using ethynyl sulfides with a terminal o-diethynylbenzene unit, an alternative strategy is demonstrated that offers selectivity advantages in the kinetically controlled radical cyclizations. The products are acene-fused thiophenes in which the diethynylsulfide acts as a relay for the diradical produced in a Bergman cyclization.
- Lewis, Kevin D.,Rowe, Michael P.,Matzger, Adam J.
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p. 7191 - 7196
(2007/10/03)
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- One-Pot Two-Step Synthesis of Aryl Sulfur Compounds by Photoinduced Reactions of Thiourea Anion with Aryl Halides
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(Equation presented) The photoinduced reactions of aryl halides with the thiourea anion afford arene thiolate ions in DMSO. These species without isolation, and by a subsequent aliphatic nucleophilic substitution, S RN1 reaction, oxidation, or protonation, yield aryl methyl sulfides, diaryl sulfides, diaryl disulfides, and aryl thiols with good yields (50-80%). This is a simple and convenient approach which involves the use of the commercially available and inexpensive thiourea in a one-pot two-step process for the synthesis of aromatic sulfur compounds.
- Argueello, Juan E.,Schmidt, Luciana C.,Penenory, Alicia B.
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p. 4133 - 4136
(2007/10/03)
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- Thiones as reactive intermediates in condensations of diketones with aromatics mediated by tetraphosphorus decasulfide
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Phenanthrene-9,10-quinone and P4S10 react with phenols on being heated to give oxathiins, e.g., 9 the dioxin 22, ethers, e.g., 14 arylphenanthrenols, e.g., 10 and furanols, e.g., 17 in addition to sulfides, e.g., 26 and disulfides, e
- Morrison, Brian J.,Musgrave, Oliver C.
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p. 2725 - 2744
(2007/10/03)
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- THERMOLYSIS AND PHOTOLYSIS OF SOME SELECTED ARYL THIOESTERS
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Aryl thioesters I and II were prepared and pyrolyzed in the absence of promotors either alone or in isoquinoline as solvent.Thermolysis of β-naphthyl thiobenzoate (I) on heating in air at 250 deg C gives benzil, benzophenone, benzoic acid, biphenyl, thio β-naphthol, 2,2'-binaphthyl, diphenyl sulfide, thianthrene, thiophenol, phenyl β-naphthyl sulfide and 2,2'-binaphthyl sulfide.Similar results were also obtained on heating p-tolyl thiobenzoate (II) under the same conditions in addition to thio p-cresol, p-bitolyl, p-ditolyl sulfide and phenyl p-tolyl sulfone.H2S and CO are also produced in all cases.Thermolysis of I and II in the presence of isoquinoline affords in addition to the above products, 1-phenylisoquinoline.Photolysis of I and II in acetone gives similar products to those of the thermolysis.From these results a free radical mechanism has been postulated to take place through the initial homolysis of C-S bond.No isomer redistribution proceeds the coupling reactions.Key words: Thermolysis, photolysis, aryl thioesters.
- El-Aal, Abd,Gaber, M.
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p. 211 - 217
(2007/10/02)
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- W(CO)6 Mediated C-S Bond Cleavage Reactions
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W(CO)6-mediated reactions of thioethers in refluxing chlorobenzene yielded mainly the corresponding dimers.Optically active thioethers give the respective racemic products.Mercaptans, on the other hand, predominantly afford the corresponding reduced products.A deuterium labeling experiments suggest that the SH group is the hydrogen source in the latter reduction reactions.A free-radical mechanism is suggested.
- Ng, Chi Tat,Wang, Xiaojun,Luh, Tien-Yau
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p. 2536 - 2539
(2007/10/02)
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- REACTIONS SRN1: PARTIE no 18. ACTION DE SULFANIONS DERIVES DE HS(CH2)nSH VIS-A-VIS DES HALO-1 ET -2 NAPHTALENES
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A double SRN1 reaction was shown to occur between HS(CH2)nSH and 1 or 2 halonaphtalene to give the corresponding double sulfides Napht1(2)-S-(CH2)n-S-Napht1(2) (n=2,3,4)
- Beugelmans, Rene,Ginsburg, Helene
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p. 413 - 414
(2007/10/02)
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