820222-00-2Relevant academic research and scientific papers
Novel triazinium-imidothioate zwitterions: Intermediates in the reaction of [1,3,4]thiadiazolo[2,3-d][1,2,4]triazolo[1,5-a][1,3,5]triazinium cations with amines
Wermann, Kurt,Walther, Martin,Günther, Wolfgang,G?rls, Helmar,Anders, Ernst
, p. 673 - 685 (2005)
Starting with bis([1,3,4]thiadiazolo)[1,3,5]triazinium halides 1, a novel class of heterocyclic compounds, the [1,3,4]thiadiazolo[2,3-d][1,2,4]triazolo[1, 5-a][1,3,5]triazinium halides 5 were prepared. The reaction between 5 and primary or secondary amines 6 yielded highly substituted guanidines 8 and fused tricyclic bis([1,2,4]triazolo)[1,5-a:1′,5′-d][1,3,5]triazinium halides 9. The formation of the reactive triazinium-imidothioate zwitterions 7, which is controlled by the influence of negative hyperconjugation, was proven by NMR data and the X-ray structure of 7c. The subsequent ring-closure/ring- opening steps can be understood in terms of an SN(ANRORC) process accompanied by intramolecular proton-transfer reactions. The zwitterions 7 were reacted with EtI forming cationic derivatives 10 or hydrolyzed at pH 6-7 to give novel heterocyclic ethanethioamides 11. Graphical Abstract.
