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4-Meth-oxy-benzamidinium 2,6-dimeth-oxy-benzoate
1Chemistry Department, "Sapienza" University of Rome, P.le A. Moro, 5, I-00185 Rome, Italy.
Acta Crystallographica. Section E, Structure Reports Online
|February 21, 2012
Summary
This study details the synthesis and crystal structure of a novel salt formed from 4-methoxy-benzamidine and 2,6-dimethoxy-benzoic acid. The compound exhibits unique non-planar arrangements and intermolecular hydrogen bonding in its crystalline state.
Area of Science:
- Organic Chemistry
- Crystallography
- Supramolecular Chemistry
Background:
- Amidine and benzoic acid derivatives are important structural motifs in medicinal chemistry and materials science.
- Understanding the solid-state structures of ionic compounds provides insights into intermolecular interactions and crystal engineering.
Purpose of the Study:
- To synthesize a novel ionic compound from 4-methoxy-benzamidine and 2,6-dimethoxy-benzoic acid.
- To elucidate the crystal structure and supramolecular architecture of the synthesized salt.
- To investigate the influence of steric hindrance on molecular conformation and hydrogen bonding.
Main Methods:
- Chemical synthesis via the reaction of 4-methoxy-benzamidine and 2,6-dimethoxy-benzoic acid.
- Single-crystal X-ray diffraction analysis to determine the three-dimensional structure.
- Analysis of hydrogen bonding and non-planar molecular conformations.
Main Results:
- The title compound, C(8)H(11)N(2)O(+)·C(9)H(9)O(4) (-), was successfully synthesized.
- The crystal structure revealed non-planar pairs of hydrogen-bonded 4-methoxy-benzamidinium cations and 2,6-dimethoxy-benzoate anions.
- The amidinium group in the cation is tilted by 27.94° relative to the benzene ring.
- The carboxylate group in the anion is twisted by 73.24° due to sterically bulky ortho-methoxy substituents.
- Intermolecular N-H⋯O hydrogen bonds form chains along the b-axis.
Conclusions:
- The synthesis yielded a well-defined ionic compound with a distinct crystal structure.
- Steric effects of the methoxy groups significantly influence the molecular geometry of both cation and anion.
- The observed hydrogen bonding pattern dictates the supramolecular assembly in the solid state.
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