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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
Butane-1,4-diammonium bis-(pyridine-2-carboxyl-ate) monohydrate
1School of Applied Chemical Engineering, the Research Institute of Catalysis, Chonnam National University, Gwangju 500-757, Republic of Korea.
Abstract:
The asymmetric unit of the title compound, C(4)H(14)N(2) (2+)·2C(6)H(4)NO(2) (-)·H(2)O, consists of half of a doubly protonated tetra-methyl-enediammonium dication, a pyridine-2-carboxyl-ate anion and half of a solvent water mol-ecule; the dication is located on a centre of inversion and a twofold rotation axis passes through the O atom of the water mol-ecule. The carboxyl-ate group of the anion appears to be delocalized on the basis of the C-O bond lengths. In the crystal structure, the components are linked by inter-molecular N-H⋯O, N-H⋯N and O-H⋯O hydrogen bonds.
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