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4-Meth-oxy-benzamidinium hydrogen sulfate
Simona Irrera1, Gustavo Portalone
1Chemistry Department, 'Sapienza' University of Rome, P. le A. Moro, 5, I-00185 Rome, Italy.
Acta Crystallographica. Section E, Structure Reports Online
|January 4, 2013
Summary
Researchers synthesized a novel salt from 4-methoxy-benzamidine and sulfuric acid. Crystal structure analysis revealed specific bonding and hydrogen bond interactions within the ionic compound.
Area of Science:
- Crystal chemistry
- Organic synthesis
- Supramolecular chemistry
Background:
- 4-methoxy-benzamidine is a key organic intermediate.
- Sulfuric acid is a common strong acid used in synthesis.
- Understanding salt structures informs material properties.
Purpose of the Study:
- To synthesize and characterize the salt formed between 4-methoxy-benzamidine and sulfuric acid.
- To elucidate the crystal structure and intermolecular interactions of the synthesized salt.
Main Methods:
- Synthesis of the title salt via reaction of 4-methoxy-benzamidine with sulfuric acid.
- Single-crystal X-ray diffraction analysis to determine the crystal structure.
- Analysis of bond lengths, bond angles, and hydrogen bonding patterns.
Main Results:
- Successful synthesis of the 4-methoxy-benzamidinium hydrogen sulfate salt.
- The asymmetric unit contains a nonplanar 4-methoxy-benzamidinium cation and a hydrogen sulfate anion.
- Identical C-N bond lengths in the amidinium group (1.306(2) and 1.308(2) Å).
- A small dihedral angle (6.49(8)°) between the amidinium group plane and the benzene ring plane.
- Crystal packing is dominated by N-H(+)⋯O(-) and O-H⋯O(-) hydrogen bonds, forming chains along the b-axis.
Conclusions:
- The crystal structure of 4-methoxy-benzamidinium hydrogen sulfate has been determined.
- The hydrogen bonding network plays a crucial role in the crystal packing and stability of the salt.
- This study provides insights into the structural features and intermolecular forces of organic-inorganic salts.
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