An efficient base-catalyzed, metal-free method for the
synthesis of 5-amino-1,2,3-triazole-4-N-sulfonyl- and arylimidamides, directed
by the structure of the amidine group, has been developed. It is based on a
previously unknown tandem process involving cycloaddition reaction to 3,3-
diaminoacrylonitriles (2-cyanoacetamidines) with aryl(alkyl)sulfonyl or aryl
azides and Cornforth-type rearrangement. During the reaction optimization,
different factors were found to facilitate the title reaction, which include the
use of a strong base and N-mono- or N,N′-disubstituted 3,3-diaminoacrylonitriles.
The reaction is tolerant to variously N-monosubstituted and N,N′-disubstituted 3,3-diaminoacrylonitriles and to various aryland
aryl/alkyl sulfonyl azides. The developed method has a broad scope and can be applied to obtain a variety of 5-amino-1,2,3-
triazole-4-carbimidamides bearing at the N1 position alkyl, allyl, propargyl, benzyl, cycloalkyl, and heteroaryl substituents and
sulfonyl and aryl substituents at the amidine group. Post-cyclization reactions of prepared 5-amino-1,2,3-triazoles with DMF-DMA
DMA-DMF leads to 1,2,3-triazolo[4,5-d]pyrimidines, 8-aza purine analogues demonstrating the applicability of the prepared
compounds in organic synthesis.