Browsing by Subject "Heterocycle"
Now showing items 1-8 of 8
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Article
1,2,3-Dithiazole chemistry in heterocyclic synthesis
(2006)The chemistry of various 5H-1,2,3-dithiazoles is investigated with emphasis on assisted ring opening and ring closure reactions leading to new heterocycles. Thus on treatment with catalytic tetraalkylammonium iodide ...
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Article
3-amino-6-ethoxy-4-phenyl-1H-pyrrolo[2,3-b]pyridine-2,5-dicarbonitrile
(2010)(Z)-2-(4-Chloro-5H-1,2,3-dithiazol-5-ylideneamino)-6-ethoxy-4-phenylpyridine- 3,5-dicarbonitrile 1, when treated with either triphenylphosphine (4 equiv.) or polymer bound triphenylphosphine (5 equiv.) in dichloromethane ...
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Article
4-chloro-6-ethoxy-2-(Methylthio)pyrimidine
(2017)4,6-Dichloro-2-(methylthio) pyrimidine (3) reacts with EtONa in EtOH, at ca. 20 °C, for 2 h, to give exclusively 4-chloro-6-ethoxy-2-(methylthio)pyrimidine (5) in 89% yield. The latter is presented as a useful multifunctionalised ...
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Article
The preparation and characterization of 5-substituted-4-chloro-1,2,3- dithiazolium salts and their conversion into 4-substituted-3-chloro-1,2,5- thiadiazoles
(2005)A series of monosubstituted acetonitriles were treated with disulfur dichloride at room temperature in CH2Cl2 to afford 5-substituted-4-chloro-1,2,3-dithiazolium chlorides 1. Where the 5-substituent was not a good leaving ...
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Article
A qualitative comparison of the reactivities of 3,4,4,5-Tetrachloro-4H-1,2,6-thiadiazine and 4,5-Dichloro-1,2,3-dithiazolium Chloride
(2015)The high yielding transformations of 3,4,4,5-tetrachloro-4H-1,2,6-thiadiazine into 3,5-dichloro-4H-1,2,6-thiadiazin-4-one (up to 85%) and 2-(3,5-dichloro-4H-1,2,6- thiadiazin-4-ylidene)malononitrile (up to 83%) have been ...
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Article
Regioselective geminal dichloride reactivity of 3,4,4,5-tetrachloro-4H-1,2,6-thiadiazine: Access to 4,4-dioxo- and dithio-ketals
(2016)Treatment of 3,4,4,5-tetrachloro-4H-1,2,6-thiadiazine (2) with selected alkanols, arenols and thiols led to regiospecific substitution of both geminal C-4 chlorines resulting in the formation of ketal or thioketal ...
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Article
Synthesis of 2-(4H-1,2,6-thiadiazin-4-ylidene)malononitriles
(2014)The base-free TiCl4-mediated condensation of 3,5-disubstituted-4H-1,2,6-thiadiazin-4-ones 8 with malononitrile affords 20 difficult to access (3,5-disubstituted-4H-1,2,6-thiadiazin-4-ylidene)malononitriles 7. The reaction ...
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Article
(Z)-2-(4-chloro-5h-1,2,3-dithiazol-5-ylideneamino)-6-ethoxy-4-phenylpyridine-3,5-dicarbonitrile
(2010)2-Amino-6-ethoxy-4-phenylpyridine-3,5-dicarbonitrile 1 reacts with 4,5-dichloro-1,2,3-dithiazolium chloride 2 in the presence of pyridine (2 equiv.) to afford (Z)-2-(4-chloro-5H-1,2,3-dithiazol-5-ylideneamino)-6-ethoxy-4 ...