3,4-Bis(bromomethyl)thieno[2,3-b]thiophene: Versatile Precursors for Novel Bis(triazolothiadiazines), Bis(quinoxalines), Bis(dihydrooxadiazoles), and Bis(dihydrothiadiazoles)
| Autor: | Ahmad M. Farag, Ahmed E. M. Mekky, Ahmed H. M. Elwahy, Osama M. Sayed |
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| Rok vydání: | 2015 |
| Předmět: |
chemistry.chemical_classification
010405 organic chemistry Organic Chemistry Oxadiazole 010402 general chemistry 01 natural sciences Aldehyde Medicinal chemistry 0104 chemical sciences Catalysis chemistry.chemical_compound Acetic anhydride chemistry Thiophene Organic chemistry Piperidine Acetonitrile Triethylamine |
| Zdroj: | Journal of Heterocyclic Chemistry. 53:1113-1120 |
| ISSN: | 0022-152X |
| DOI: | 10.1002/jhet.2373 |
| Popis: | A synthesis of novel bis(triazolothiadiazines) 11, 12, 13, 14, bis(quinoxalines) 16 and 17, bis(thiadiazoles) 24 and 25, and bis(oxadiazole) 31, which are linked to the thieno[2,3-b]thiophene core via phenoxymethyl group, was reported. Thus, reaction of the bis(α-bromoketones) 6 and 7 with the corresponding 4-amino-3-mercapto-1,2,4-triazole derivatives 8, 9, 10 in ethanol–DMF mixture in the presence of a few drops of triethylamine as a catalyst under reflux afforded the novel bis(5,6-dihydro-s-triazolo[3,4-b]thiadiazines) 11, 12, 13, 14 in 60–72% yields. The bis(quinoxalines) 16 and 17 were also synthesized as a sole product in high yields by the reaction of 6 and 7 with o-phenylenediamine 15 in refluxing acetonitrile in the presence of piperidine as a catalyst. Cyclization of the bis(aldehyde thiosemicarbazones) 20 and 21 with acetic anhydride afforded the corresponding bis(4,5-dihydro-1,3,4-thiadiazolyl) derivatives 24 and 25 in good yield. Bis(5-phenyl-2,3-dihydro-1,3,4-oxadiazole) derivative 31 could be obtained in 67% yield by cyclization of the appropriate bis(N-phenylhydrazone) 29 in refluxing acetic anhydride for 3 h. |
| Databáze: | OpenAIRE |
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