4-Nitro-benzoic acid-2,2'-biimidazole (2/1)
1School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China.
Summary
This study reveals how 4-nitro-benzoic acid and 2,2'-biimidazole form multi-dimensional crystal frameworks. Hydrogen bonds link these units, creating complex molecular architectures through crystallographic inversion.
Area of Science:
- Crystal engineering
- Supramolecular chemistry
- Materials science
Background:
- Understanding the self-assembly of organic molecules is crucial for designing novel materials.
- Hydrogen bonding plays a key role in directing the formation of crystalline structures.
- 2,2'-biimidazole and 4-nitro-benzoic acid are relevant building blocks in supramolecular chemistry.
Purpose of the Study:
- To investigate the crystal structure of an adduct formed between 4-nitro-benzoic acid and 2,2'-biimidazole.
- To elucidate the role of hydrogen bonding in the formation of multi-dimensional frameworks.
- To characterize the supramolecular architecture of the resulting crystal.
Main Methods:
- Single-crystal X-ray diffraction analysis was employed to determine the crystal structure.
- Hydrogen bonding interactions were identified and analyzed using graph-set descriptors.
- The crystallographic inversion center's role in generating the biimidazole molecule was examined.
Main Results:
- The title adduct, C(7)H(5)NO(4)·0.5C(6)H(6)N(4), was successfully synthesized and characterized.
- The crystal structure features a complete biimidazole molecule generated by a crystallographic inversion centre.
- N-H⋯O and O-H⋯N hydrogen bonds link the 4-nitro-benzoic acid and 2,2'-biimidazole units.
- These interactions lead to the formation of multi-dimensional frameworks described by the graph-set descriptor R(2)(2)(9).
Conclusions:
- The study successfully demonstrates the formation of intricate multi-dimensional frameworks through the co-crystallization of 4-nitro-benzoic acid and 2,2'-biimidazole.
- Hydrogen bonding interactions are confirmed as the primary driving force for the observed supramolecular assembly.
- The findings contribute to the understanding of crystal engineering principles and the design of novel crystalline materials.
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