4,4'-(1,3,4-Oxadiazole-2,5-diyl)di-pyri-dinium dibromide monohydrate

Area of Science:

• Crystallography
• Supramolecular Chemistry
• Organic Chemistry

Background:

• Understanding the three-dimensional arrangement of atoms in crystalline solids is crucial for predicting material properties.
• Hydrogen bonding plays a significant role in the self-assembly of molecules and the formation of extended networks.

Purpose of the Study:

• To elucidate the crystal structure of the title compound, C(12)H(10)N(4)O(+)·2Br(-)·H(2)O.
• To analyze the molecular geometry, including planarity and dihedral angles of the cation.
• To investigate the hydrogen bonding interactions and their contribution to the overall crystal packing.

Main Methods:

• Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
• Analysis of bond lengths, bond angles, and dihedral angles provided information on the cation's geometry.
• Intermolecular interactions, including hydrogen bonds (N-H⋯Br, O-H⋯Br, N-H⋯O) and C-H⋯N, C-H⋯Br interactions, were identified and analyzed.

Main Results:

• The cation, C(12)H(10)N(4)O(+), exhibits approximate planarity with small dihedral angles between its rings (7.91° between terminal rings, 6.02° and 6.50° with the central ring).
• The crystal structure is stabilized by a network of hydrogen bonds involving the cation, bromide anions, and water molecules (N-H⋯Br, O-H⋯Br).
• Additional weaker interactions such as C-H⋯N, C-H⋯Br, and N-H⋯O were also observed, contributing to the three-dimensional network.

Conclusions:

• The title compound forms a robust three-dimensional supramolecular network through extensive hydrogen bonding.
• The near-planar geometry of the organic cation influences crystal packing and intermolecular interactions.
• The study provides a detailed structural characterization, contributing to the understanding of organic salt crystal engineering.