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Updated: May 22, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
5-Amino-3-carb-oxy-1H-1,2,4-triazol-4-ium nitrate monohydrate
Abstract:
The two-dimensional crystal packing of the title compound, C(3)H(5)N(4)O(2) (+)·NO(2) (-)·H(2)O, results from the stacking of well separated layers (i.e. with nothing between the layers) parallel to the (-113) plane in which adjacent cations adopt a head-to-head arrangement such that two -COOH groups are linked via two water mol-ecules (the water O atom behaves simultaneously as donor and acceptor of hydrogen bonds) and two -NH(2) groups are linked through two nitrate anions. This arrangement leads to alternating hydro-philic and hydro-phobic zones in which O-H⋯O and N-H⋯O hydrogen bonds, respectively, are observed.
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