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Updated: May 20, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Bis{4-[(3,5-dimethyl-1H-pyrazol-4-yl)selan-yl]-3,5-dimethyl-1H-pyrazol-2-ium} chloride monohydrate
Abstract:
In the title compound, 2C(10)H(15)N(4)Se(+)·Cl(-)·OH(-), a singly protonated mol-ecule of the organic selenide participates in hydrogen bonding with neighboring mol-ecules, forming zigzag chains along [001]. The molecule adapts a cis bridging mode with a C-Se-C angle of 102.13 (15)°. π-π stacking inter-actions are observed between the closest pyrazole rings of neighboring chains [centroid-centroid distance = 3.888 (1) Å] and hydrogen bonding occurs through bridging chloride anions and hydroxide groups. Additionally, O-H⋯Cl hydrogen bonds are formed.
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