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Published on: June 10, 2021
3,5-Dimethyl-pyrazolium 3,5-dinitro-salicylate.
Shuaishuai Wei1, Shouwen Jin, Zhaofeng Hu
1Tianmu College of ZheJiang A & F University, Lin'An 311300, People's Republic of China.
Acta Crystallographica. Section E, Structure Reports Online
|January 4, 2013
Summary
This study characterizes a molecular salt, detailing its crystal structure. Hydrogen bonding interactions between the cation and anion form double chains, influencing the overall crystal packing.
Area of Science:
- Crystallography
- Supramolecular Chemistry
Background:
- Molecular salts are crucial in materials science.
- Understanding hydrogen bonding is key to predicting crystal structures.
Purpose of the Study:
- To elucidate the crystal structure of a novel molecular salt.
- To investigate the role of hydrogen bonding in its assembly.
Main Methods:
- Single-crystal X-ray diffraction was employed.
- Analysis of intermolecular interactions, including hydrogen bonds.
Main Results:
- The crystal structure of C(5)H(9)N(2)(+)·C(7)H(3)N(2)O(7)(-) was determined.
- The anion exhibits deprotonation at the phenol group and forms an intramolecular hydrogen bond (S(6) ring).
- Cation-anion hydrogen bonds (N-H⋯O) create [010] double chains, with weak C-H⋯O interactions stabilizing the packing.
Conclusions:
- The crystal structure is dictated by a combination of intra- and intermolecular hydrogen bonding.
- The identified hydrogen bonding motifs provide insights into the self-assembly of molecular salts.
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01:11Aryldiazonium Salts to Azo Dyes: Diazo Coupling
The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the para position.