A new site-selective route for synthesis of functionalized imidazo[2,1-c][1,2,4]triazoles
โ Scribed by Ahmad S. Shawali; Magda A. Abdallah; Mosselhi A. N. Mosselhi; Mahmoud S. Elewa
- Publisher
- Journal of Heterocyclic Chemistry
- Year
- 2007
- Tongue
- English
- Weight
- 287 KB
- Volume
- 44
- Category
- Article
- ISSN
- 0022-152X
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โฆ Synopsis
Abstract
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Reactions of 4โarylhydrazonoโ2โmethylthioโimidazolinโ5(1__H__)โone 3 with various hydrazonoyl halides 1 proved to be siteโselective and yielded the respective imidazo[2,1โc][1,2,4]triazole derivatives 8. The structure of the latter was elucidated by Xโray analysis and the mechanism of the studied reactions was discussed.
๐ SIMILAR VOLUMES
## Abstract The reaction of benzil 1โureidoethylidene hydrazones 8 with a mixture of triphenylphosphine, carbon tetrachloride, and triethylamine provides a general route to 7__H__โimidazo[1,2โ__b__][1,2,4]triazoles 18 __via__ the thermal reaction of the expected keto azine carbodiimide intermediate
Hydrazonoyl bromides 1a-c react with 5-amino-3phenyl-1H-pyrazole, 5-amino-1H-1,2,4-triazole, 2aminopyridine, 2-aminopyrimidine, and 2-aminobenzimidazole to afford the corresponding imidazo[1,2-b]pyrazoles 10, imidazo[1,2-b]-1,2,4-triazoles 11, imidazo[1,2-a]pyridines 16, imidazo[1,2-a]pyrimidines 17