Synthesis of substituted 5H-imidazo[1,2-e][1,3,5]triazepines

TitleSynthesis of substituted 5H-imidazo[1,2-e][1,3,5]triazepines
Publication TypeJournal Article
Year of Publication2020
AuthorsDemydchuk, BA, Sushchenko, IO, Mikhalchenko, OA, Sukhoveev, VV, Brovarets, VS
Abbreviated Key TitleDopov. Nac. akad. nauk Ukr.
Date Published4/2020

A preparative method for the synthesis of previously unknown substituted 5H-imidazo[1,2-e][1,3,5]triazepines was developed based on the available reagents. Thus, the interaction of aromatic acid amides with chloral leads to chloralamides, which are subsequently converted into imidoylchlorides by the action of phosphorus pentachloride. The latter, when treated with triethylamine, give tetrachloro-2-aza-1,3-butadiene. The interaction of them with 2-(aminomethyl)imidazole proceeds regioselectively on the primary amino group with the formation of intermediates, the prototropy of which promotes the intramolecular heterocyclization with the participation of the imidoyl chloride moiety and the endocyclic nitrogen atom of the imidazole. As a result of all these transformations, a regioselective annulation to the imidazole of the triazepine cycle occurs to give in high yields the first representatives of the new 5H-imidazo[1,2-e][1,3,5]triazepine heterocyclic system. Their structure was reliably proven with the help of the modern spectral studies and X-ray diffraction analysis.

Keywords2-(aminomethyl)imidazole, 2-e][1, 3, 3-butadienes, 5]triazepines, imidazo[1, regioselective annulation, tetrachloro-2-aza-1

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