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Gotard Burdzinski - One of the best experts on this subject based on the ideXlab platform.
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the photochemistry of 4 5 carbomethoxy 1 2 3 thiadiazole direct observation of Thiirene formation and its decay in solution
Journal of Physical Chemistry A, 2013Co-Authors: Gotard Burdzinski, Yunlong Zhang, Carolyn S Reid, Christopher M Hadad, Matthew S PlatzAbstract:The photochemistry of 4,5-carbomethoxy-1,2,3-thiadiazole in solution was studied at room temperature with use of UV–vis and IR transient absorption spectroscopies (λex = 266 nm). Ultrafast time-resolved techniques demonstrate that there is a very fast rise (<0.4 ps) of bis(carbomethoxy)Thiirene in acetonitrile, and that it is the only intermediate formed. The lifetime of the Thiirene is limited by dimerization to eventually form tetra(carbomethoxy)thiophene.
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The Photochemistry of 4,5-Carbomethoxy-1,2,3-thiadiazole: Direct Observation of Thiirene Formation and Its Decay in Solution
Journal of Physical Chemistry A, 2013Co-Authors: Gotard Burdzinski, Yunlong Zhang, Carolyn S Reid, Christopher M Hadad, Matthew S PlatzAbstract:The photochemistry of 4,5-carbomethoxy-1,2,3-thiadiazole in solution was studied at room temperature with use of UV–vis and IR transient absorption spectroscopies (λex = 266 nm). Ultrafast time-resolved techniques demonstrate that there is a very fast rise (
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photochemical formation of Thiirene and thioketene in 1 2 3 thiadiazoles with phenyl substituents studied by time resolved spectroscopy
Photochemical and Photobiological Sciences, 2013Co-Authors: Gotard Burdzinski, Michel Sliwa, Yunlong Zhang, Stephanie Delbaere, Tomasz Pedzinski, Julien RehaultAbstract:Photochemistry of 4-phenyl-1,2,3-thiadiazole (PT) and 4,5-diphenyl-1,2,3-thiadiazole (DPT) in solution was studied at room temperature using UV-vis and IR transient absorption spectroscopies (λex = 266 nm). Ultrafast techniques show a very fast rise (<0.3 ps) of Thiirene and thioketene species, formed from 1,2,3-thiadiazoles in the singlet excited state. The remarkable unimolecular stability of Thiirenes in solution is observed. On a millisecond time scale Thiirenes with phenyl substituents undergo an intermolecular reaction (dimerization of Thiirene–thioketene complexes) leading to 1,3-dithiole derivatives.
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Photochemical formation of Thiirene and thioketene in 1,2,3-thiadiazoles with phenyl substituents studied by time-resolved spectroscopy
Photochemical and Photobiological Sciences, 2013Co-Authors: Gotard Burdzinski, Michel Sliwa, Yunlong Zhang, Stephanie Delbaere, Tomasz Pedzinski, Julien RehaultAbstract:Photochemistry of 4-phenyl-1,2,3-thiadiazole (PT) and 4,5-diphenyl-1,2,3-thiadiazole (DPT) in solution was studied at room temperature using UV-vis and IR transient absorption spectroscopies (λex = 266 nm). Ultrafast techniques show a very fast rise (
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Early events in the photochemistry of 1,2,3-thiadiazole studied by ultrafast time-resolved UV-vis and IR spectroscopies.
Journal of Physical Chemistry A, 2011Co-Authors: Gotard Burdzinski, Michel Sliwa, Yunlong Zhang, Stephanie DelbaereAbstract:Photochemistry of 4-methyl-5-carboethoxy-1,2,3-thiadiazole (MCT) in solution was studied at room temperature using UV–vis and IR transient absorption spectroscopies (λex = 266 nm). Three deactivation pathways are discussed: Thiirene formation, thioketene generation, and the internal conversion by repopulating MCT in the ground state. Ultrafast techniques show a very fast rise (
Juzo Nakayama - One of the best experts on this subject based on the ideXlab platform.
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[1 + 2] Cycloadditions of Sulfur Monoxide (SO) to Alkenes and Alkynes and [1 + 4] Cycloadditions to Dienes (Polyenes). Generation and Reactions of Singlet SO?
Journal of the American Chemical Society, 2007Co-Authors: Juzo Nakayama, Yumi Tajima, Yoshiaki SugiharaAbstract:The Diels−Alder adduct, produced from 3,4-di-tert-butylthiophene 1-oxide and dimethyl acetylenedicarboxylate, spontaneously extrudes sulfur monoxide (SO) at room temperature and serves as a new method for generation of SO under mild conditions. Thus, the SO generated underwent [1 + 2] cycloadditions to a series of alkenes and alkynes to produce thiirane oxides and Thiirene 1-oxides, respectively, providing new syntheses of the sulfur-containing three-membered heterocycles. The SO also reacted with a variety of cyclic and acyclic dienes to give the corresponding 2,5-dihydrothiophene 1-oxides.
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Synthesis and characterization of aliphatic alpha-dithiones, di(1-adamantyl)- and di-tert-butylethanedithiones.
Journal of the American Chemical Society, 2003Co-Authors: Yoshiaki Sugihara, And Akihiko Ishii, Juzo NakayamaAbstract:2,3-Di(1-adamantyl)Thiirene 1-oxide quickly reacted with Lawesson's reagent in CH2Cl2 at room temperature to provide di(1-adamantyl)ethanedithione (1) as thermally labile, violet crystals in 20% is...
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Conversions of Thiirene 1-Oxides to α-Iminothioketones or Oxazoles through Probable Intermediates Sulfilimines
Chemistry Letters, 2002Co-Authors: Yoshiaki Sugihara, Akihiko Ishii, Juzo NakayamaAbstract:Three Thiirene 1-oxides 1, which possess bulky alkyl substituents at the 2- and 3-positions, afforded α-iminothio-ketones in 59–69% yields on successive treatment with trifluoroacetic anhydride and p-toluenesulfonamide, whereas 1 furnished oxazoles in 65–89% yields on the same treatment with trifluoroacetic anhydride and p-toluamide. A mechanism involving ring-expansion of the initial intermediates, sulfilimines, is proposed for these reactions.
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practical synthesis of Thiirene 1 oxides that possess two bulky alkyl substituents
Heteroatom Chemistry, 2002Co-Authors: Juzo Nakayama, Yoshiaki Sugihara, Kenta Takahashi, Michiyo Morita, 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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a convenient synthesis of Thiirene 1 oxides
Tetrahedron Letters, 2001Co-Authors: Juzo Nakayama, Yoshiaki Sugihara, Kenta Takahashi, Akihiko IshiiAbstract:Abstract Acetylenes ( 1 ), carrying two bulky alkyl substituents, reacted with sulfur dichloride (ClSCl) to give 2,3-dialkyl-2,3-dichlorothiiranes ( 2 ) nearly quantitatively. The alkaline hydrolysis of crude 2 resulted in the formation of Thiirene 1-oxides ( 3 ) in 68–90% yields based on 1 , thus providing a convenient synthesis of 3 .
Akihiko Ishii - One of the best experts on this subject based on the ideXlab platform.
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Conversions of Thiirene 1-Oxides to α-Iminothioketones or Oxazoles through Probable Intermediates Sulfilimines
Chemistry Letters, 2002Co-Authors: Yoshiaki Sugihara, Akihiko Ishii, Juzo NakayamaAbstract:Three Thiirene 1-oxides 1, which possess bulky alkyl substituents at the 2- and 3-positions, afforded α-iminothio-ketones in 59–69% yields on successive treatment with trifluoroacetic anhydride and p-toluenesulfonamide, whereas 1 furnished oxazoles in 65–89% yields on the same treatment with trifluoroacetic anhydride and p-toluamide. A mechanism involving ring-expansion of the initial intermediates, sulfilimines, is proposed for these reactions.
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practical synthesis of Thiirene 1 oxides that possess two bulky alkyl substituents
Heteroatom Chemistry, 2002Co-Authors: Juzo Nakayama, Yoshiaki Sugihara, Kenta Takahashi, Michiyo Morita, 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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a convenient synthesis of Thiirene 1 oxides
Tetrahedron Letters, 2001Co-Authors: Juzo Nakayama, Yoshiaki Sugihara, Kenta Takahashi, Akihiko IshiiAbstract:Abstract Acetylenes ( 1 ), carrying two bulky alkyl substituents, reacted with sulfur dichloride (ClSCl) to give 2,3-dialkyl-2,3-dichlorothiiranes ( 2 ) nearly quantitatively. The alkaline hydrolysis of crude 2 resulted in the formation of Thiirene 1-oxides ( 3 ) in 68–90% yields based on 1 , thus providing a convenient synthesis of 3 .
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reactions of acetylenes possessing bulky alkyl substituents with s2cl2 unexpected formation of α oxothioketones Thiirene 1 oxides and 1 2 dithietes
Tetrahedron Letters, 2000Co-Authors: Juzo Nakayama, Yoshiaki Sugihara, Kenta Takahashi, Toshiaki Watanabe, Akihiko IshiiAbstract:Abstract The reaction of di-t-butylacetylene with S2Cl2, followed by purification with silica-gel column chromatography, gave 2,2,5,5-tetramethyl-4-oxo-3-hexanethione (4a) (37%) and 2,3-di-t-butylThiirene 1-oxide (5a) (10%), which were formed by hydrolysis of the initial product, 2,3-di-t-butyl-2,3-dichloroepisulfide (3a). The same work-up of the reaction mixture of di(1-adamantyl)acetylene with S2Cl2 provided 2-oxoethanethione (4b) (4–33%), Thiirene 1-oxide (5b) (8–27%) and 1,2-dithiete (9b) (3–21%). The reaction of 2,2,5,5,6,6,9,9-octamethyl-3,7-decadiyne (1c) with S2Cl2 furnished a 4H,5H-thiepin (12) as the sole product in 99% yield.
Yoshiaki Sugihara - One of the best experts on this subject based on the ideXlab platform.
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[1 + 2] Cycloadditions of Sulfur Monoxide (SO) to Alkenes and Alkynes and [1 + 4] Cycloadditions to Dienes (Polyenes). Generation and Reactions of Singlet SO?
Journal of the American Chemical Society, 2007Co-Authors: Juzo Nakayama, Yumi Tajima, Yoshiaki SugiharaAbstract:The Diels−Alder adduct, produced from 3,4-di-tert-butylthiophene 1-oxide and dimethyl acetylenedicarboxylate, spontaneously extrudes sulfur monoxide (SO) at room temperature and serves as a new method for generation of SO under mild conditions. Thus, the SO generated underwent [1 + 2] cycloadditions to a series of alkenes and alkynes to produce thiirane oxides and Thiirene 1-oxides, respectively, providing new syntheses of the sulfur-containing three-membered heterocycles. The SO also reacted with a variety of cyclic and acyclic dienes to give the corresponding 2,5-dihydrothiophene 1-oxides.
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Synthesis and characterization of aliphatic alpha-dithiones, di(1-adamantyl)- and di-tert-butylethanedithiones.
Journal of the American Chemical Society, 2003Co-Authors: Yoshiaki Sugihara, And Akihiko Ishii, Juzo NakayamaAbstract:2,3-Di(1-adamantyl)Thiirene 1-oxide quickly reacted with Lawesson's reagent in CH2Cl2 at room temperature to provide di(1-adamantyl)ethanedithione (1) as thermally labile, violet crystals in 20% is...
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Conversions of Thiirene 1-Oxides to α-Iminothioketones or Oxazoles through Probable Intermediates Sulfilimines
Chemistry Letters, 2002Co-Authors: Yoshiaki Sugihara, Akihiko Ishii, Juzo NakayamaAbstract:Three Thiirene 1-oxides 1, which possess bulky alkyl substituents at the 2- and 3-positions, afforded α-iminothio-ketones in 59–69% yields on successive treatment with trifluoroacetic anhydride and p-toluenesulfonamide, whereas 1 furnished oxazoles in 65–89% yields on the same treatment with trifluoroacetic anhydride and p-toluamide. A mechanism involving ring-expansion of the initial intermediates, sulfilimines, is proposed for these reactions.
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practical synthesis of Thiirene 1 oxides that possess two bulky alkyl substituents
Heteroatom Chemistry, 2002Co-Authors: Juzo Nakayama, Yoshiaki Sugihara, Kenta Takahashi, Michiyo Morita, 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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a convenient synthesis of Thiirene 1 oxides
Tetrahedron Letters, 2001Co-Authors: Juzo Nakayama, Yoshiaki Sugihara, Kenta Takahashi, Akihiko IshiiAbstract:Abstract Acetylenes ( 1 ), carrying two bulky alkyl substituents, reacted with sulfur dichloride (ClSCl) to give 2,3-dialkyl-2,3-dichlorothiiranes ( 2 ) nearly quantitatively. The alkaline hydrolysis of crude 2 resulted in the formation of Thiirene 1-oxides ( 3 ) in 68–90% yields based on 1 , thus providing a convenient synthesis of 3 .
Yunlong Zhang - One of the best experts on this subject based on the ideXlab platform.
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the photochemistry of 4 5 carbomethoxy 1 2 3 thiadiazole direct observation of Thiirene formation and its decay in solution
Journal of Physical Chemistry A, 2013Co-Authors: Gotard Burdzinski, Yunlong Zhang, Carolyn S Reid, Christopher M Hadad, Matthew S PlatzAbstract:The photochemistry of 4,5-carbomethoxy-1,2,3-thiadiazole in solution was studied at room temperature with use of UV–vis and IR transient absorption spectroscopies (λex = 266 nm). Ultrafast time-resolved techniques demonstrate that there is a very fast rise (<0.4 ps) of bis(carbomethoxy)Thiirene in acetonitrile, and that it is the only intermediate formed. The lifetime of the Thiirene is limited by dimerization to eventually form tetra(carbomethoxy)thiophene.
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The Photochemistry of 4,5-Carbomethoxy-1,2,3-thiadiazole: Direct Observation of Thiirene Formation and Its Decay in Solution
Journal of Physical Chemistry A, 2013Co-Authors: Gotard Burdzinski, Yunlong Zhang, Carolyn S Reid, Christopher M Hadad, Matthew S PlatzAbstract:The photochemistry of 4,5-carbomethoxy-1,2,3-thiadiazole in solution was studied at room temperature with use of UV–vis and IR transient absorption spectroscopies (λex = 266 nm). Ultrafast time-resolved techniques demonstrate that there is a very fast rise (
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photochemical formation of Thiirene and thioketene in 1 2 3 thiadiazoles with phenyl substituents studied by time resolved spectroscopy
Photochemical and Photobiological Sciences, 2013Co-Authors: Gotard Burdzinski, Michel Sliwa, Yunlong Zhang, Stephanie Delbaere, Tomasz Pedzinski, Julien RehaultAbstract:Photochemistry of 4-phenyl-1,2,3-thiadiazole (PT) and 4,5-diphenyl-1,2,3-thiadiazole (DPT) in solution was studied at room temperature using UV-vis and IR transient absorption spectroscopies (λex = 266 nm). Ultrafast techniques show a very fast rise (<0.3 ps) of Thiirene and thioketene species, formed from 1,2,3-thiadiazoles in the singlet excited state. The remarkable unimolecular stability of Thiirenes in solution is observed. On a millisecond time scale Thiirenes with phenyl substituents undergo an intermolecular reaction (dimerization of Thiirene–thioketene complexes) leading to 1,3-dithiole derivatives.
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Photochemical formation of Thiirene and thioketene in 1,2,3-thiadiazoles with phenyl substituents studied by time-resolved spectroscopy
Photochemical and Photobiological Sciences, 2013Co-Authors: Gotard Burdzinski, Michel Sliwa, Yunlong Zhang, Stephanie Delbaere, Tomasz Pedzinski, Julien RehaultAbstract:Photochemistry of 4-phenyl-1,2,3-thiadiazole (PT) and 4,5-diphenyl-1,2,3-thiadiazole (DPT) in solution was studied at room temperature using UV-vis and IR transient absorption spectroscopies (λex = 266 nm). Ultrafast techniques show a very fast rise (
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Early events in the photochemistry of 1,2,3-thiadiazole studied by ultrafast time-resolved UV-vis and IR spectroscopies.
Journal of Physical Chemistry A, 2011Co-Authors: Gotard Burdzinski, Michel Sliwa, Yunlong Zhang, Stephanie DelbaereAbstract:Photochemistry of 4-methyl-5-carboethoxy-1,2,3-thiadiazole (MCT) in solution was studied at room temperature using UV–vis and IR transient absorption spectroscopies (λex = 266 nm). Three deactivation pathways are discussed: Thiirene formation, thioketene generation, and the internal conversion by repopulating MCT in the ground state. Ultrafast techniques show a very fast rise (