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Updated: Jun 1, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
2-Amino-5-bromo-pyridinium 6-oxo-1,6-dihydro-pyridine-2-carboxyl-ate monohydrate
Madhukar Hemamalini1, Hoong-Kun Fun
1X-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia.
Abstract:
In the crystal structure of the title salt, C(5)H(6)BrN(2) (+)·C(6)H(4)NO(3) (-)·H(2)O, the protonated N atom and the 2-amino group of the cation are hydrogen bonded to the carboxyl-ate O atoms of the anion via a pair of N-H⋯O hydrogen bonds, forming an R(2) (2)(8) ring motif. The ion pairs are further connected via O-H⋯O, N-H⋯O, N-H⋯Br and C-H⋯O hydrogen bonds, forming a two-dimensional network parallel to the bc plane. The water mol-ecules self-assemble through O-H⋯O hydrogen bonds, forming one-dimensional supra-molecular chains along the a axis, with graph-set notation C(2) (2)(4).
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