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1-Methyl-piperazine-1,4-diium dipicrate
Acta Crystallographica. Section E, Structure Reports Online
|April 28, 2011
Summary
The crystal structure of 1-methyl-piperazine-1,4-diium bis-(2,4,6-trinitro-phen-ol-ate) reveals hydrogen bonds forming conglomerates. Weak interactions and stacking also contribute to the crystal packing of this compound.
Area of Science:
- Crystallography
- Chemical Physics
Background:
- Understanding molecular interactions is key in crystal engineering.
- Picrate salts are known for their energetic properties and complex structures.
Purpose of the Study:
- To elucidate the crystal structure of 1-methyl-piperazine-1,4-diium bis-(2,4,6-trinitro-phen-ol-ate).
- To analyze the intermolecular interactions governing the crystal packing.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the atomic arrangement.
- Analysis of hydrogen bonds (N-H⋯O) and weaker interactions (C-H⋯O) was performed.
Main Results:
- The crystal structure features centrosymmetric six-membered conglomerates formed by two dications and four anions linked by N-H⋯O hydrogen bonds.
- Weak C-H⋯O interactions and pi-stacking between picrate anions were observed.
- The piperazine ring adopts a chair conformation, and nitro group twist angles in picrate anions vary based on position relative to the phenolate.
Conclusions:
- The crystal structure is primarily governed by strong N-H⋯O hydrogen bonds, forming stable supramolecular assemblies.
- The observed interactions provide insights into the packing efficiency and stability of the crystalline material.
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