- Syntheses of 6,6'-Bi-1,3-Thiazinylidene Derivatives
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The high tendency of formation of 6,6'-bi-1,3-thiazylidenes renders these compounds available by several synthetic routes and with various substitution patterns.Methods for their synthesis described here consist of the reaction of 6-alkylthio- or 6-arylth
- Schroth, Werner,Spitzner, Roland,Freitag, Sabine,Richter Monika,Dobner, Bodo
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p. 916 - 920
(2007/10/02)
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- Complexes a transfert de charge a caractere metallique a partir de donneurs d'electrons derives de bis(chalcogenopyrannylidenes)
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The synthesis of electron donor compounds in the 2:2' and 4:4'-bi(thiopyranyliden) series and 4:4'-bi(selenopyranyliden) series is described following several ways.The Z structure of the 2:2'-bi(4,6-diarylthiopyranyliden) is established by means of dipole
- Es-Seddiki, Said,Hakiki, Mahjouba,Coustumer, Gerard Le,Mollier, Yves,Mottier, Christine Regnault Du,Sauve, Jean-Pierre
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p. 241 - 246
(2007/10/02)
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- Composes sulfures heterocycliques. LXXXVIII. Bromures et iodures de -2 thiopyrylium
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In boiling acetic acid, 2-acylmethylthio-thiopyrylium bromides 1 yield 2-(thiopyran-2-ylidenemethyl)thiopyrylium bromides 2.Best results are obtained with derivatives of acetone (R=CH3). In strong acidic medium, compounds 2 are protonated and the resulting species exists in two conformations when the thiopyran rings are substituted in the 3-position, as shown by NMR spectra in deuteriotrifluoracetic acid.The α-thiopyranylidene-ketone derived from 1 seems to be an intermediate in the mechanism which leads to the (thiopyranylidenemethyl)thiopyrylium bromide 2. Another way to this type of molecules is the action of a 2-methyl-thiopyrylium iodide on malonic acid.The compound 2 is, in this case, obtained as an iodide.A similar reaction has been observed in the 1,2-dithiole series.In the basic medium used for its preparation, the 1,2-dithiole compound rearranges whereas the 2-thiopyran compound 2 is stable and remains unchanged.
- Sauve, Jean-Pierre
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p. 434 - 440
(2007/10/02)
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- COMPOSES SULFURES HETEROCYCLIQUES. XCIII (1). ACTION DU DIAZOACETATE D'ETHYLE ET DE DIAZOCETONES SUR LES THIOPYRANNETHIONES-2
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Ethyl diazoacetate reacts with 4,6-diarylthiopyran-2-thiones 1 giving diethyl α,α'-bis(4,6-diarylthiopyran-2-ylidene)-α,α'-dithioacetates 2 and traces of bis(thiopyran-2-ylidene) 3. We have never obtained the expected ethyl thiopyranylidene-acetate, but the disulfides 2, whose structures have been confirmed by NMR and IR spectra.With diazoacetone, in all cases, α-thiopyran-2-ylidene-acetone 4 is formed.According to the substituents of the thiopyran ring, the compounds 5, 6 and 7 are also obtained.Compounds 4, 5 and 6 are probably formed through a same thiiranne intermediate.Unsubstituted thiopyran-2-thione yields thiopyran-2-ylidene-acetone 4, the disulfide 6 and small quantities of thieno-1,2-dithiole-3-thione 7.With a large excess of diazoacetone, the reaction leads only to α-acetonylthio-α-thiopyranylidene-acetone 5. 3,5 Dialkylthiopyran-2-thiones only yield the corresponding thiopyranylideneacetone 4 whereas 4,6-diarylthiopyran-2-thiones give simultaneously all the compounds 3,4,5 and 6.With diazoacetophenone, α-(thiopyran-2-ylidene)acetophenone 8 is always the only product obtained, whatever the substituents of the thiopyran ring may be.
- Sauve, Jean-Pierre
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p. 582 - 587
(2007/10/02)
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