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Updated: May 31, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
2,4-Dichloro-anilinium 4-chloro-benzene-sulfonate monohydrate
Abstract:
The asymmetric unit of the title compound, C(6)H(6)Cl(2)N(+)·C(6)H(4)ClO(3)S(-)·H(2)O, contains two 2,4-dichloro-anilinium cations, two 4-chloro-phenyl-sulfonate anions and two water mol-ecules. The three H atoms of the positively charged NH(3) group have two O atoms of the negatively charged sulfonate anion and one O atom of the water mol-ecule as acceptors. Similarly, the two H atoms of the water mol-ecule have two O atoms of two different negatively charged sulfonate anions as acceptors. Further, one of the O atoms of the sulfonate anion is involved in simultaneous hydrogen bonds with two H atoms, one from the positively charged NH(3) group and the other from the water mol-ecule. In the crystal, mol-ecules are packed into a layer structure through N-H⋯O(S), N-H⋯O(H(2)O) and N-H⋯O(S)⋯H-O(H(2)O) (three-centre) hydrogen bonding, the chains running along the c axis.
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