Ring opening of [1,2,3]triazolo[1,5-a]pyrazinium salts: Synthesis and some transformations of a novel type of 2-aza-1,3-butadienes

Article abstract of DOI:10.1016/S0040-4020(97)00591-7

The synthesis of 1,3-disubstituted [1.2.3]triazolo[1,5-a]pyrazinium salts 6 and subsequent ring opening induced by the reaction with pyrrolidine provides a facile access to 4-(1-pyrrolidino)-1-([1,2,3] triazol-5-yl)-2-aza-1,3-butadienes 7, a new type of 2-aza-1,3-butadienes. Compounds 7 proved to be suitable starting materials for further ring formation reactions.