Communications

4-(Propargylthio)sydnone imines: synthesis and reactivity in the azide–alkyne cycloaddition

N. V. Kalganova^a, D. N. Bryksin^b, A. F. Smol'yakov^a, I. A. Cherepanov<sup>a

a</sup> A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 119334 Moscow, Russian Federation
^b D. Mendeleev University of Chemical Technology of Russia, 125047 Moscow, Russian Federation

Abstract: A convenient and general method has been developed for the synthesis of previously scarcely accessible sydnone imines bearing a terminal alkyne moiety via the lithiation at the position 4 followed by treatment with propargyl bromide. The thus obtained 4-propargylthio derivatives were subjected to azide–alkyne cycloaddition to produce the corresponding 1,2,3-triazole–sydnone imine conjugates. For the first time, a lipoic acid conjugate incorporating the NO-donor fragment of Molsidomine has been synthesized.

Keywords: sydnone imines, terminal acetylenes, mesoionic compounds, NO donors, azide–alkyne cycloaddition, lithiation, sulfides.

Received: 03.09.2025
Accepted: 06.10.2025

Language: English

DOI: 10.71267/mencom.7908