Guanidinium quinoline-2-carboxyl-ate

Area of Science:

• Crystallography
• Supramolecular Chemistry
• Organic Chemistry

Background:

• Guanidinium salts and quinaldic acid derivatives are important in various chemical applications.
• Understanding the solid-state structure of such compounds is crucial for predicting their properties.
• Hydrogen bonding and π-π interactions are key non-covalent forces dictating crystal packing.

Purpose of the Study:

• To elucidate the crystal structure of the guanidinium salt of quinaldic acid.
• To analyze the hydrogen bonding networks and π-π interactions present in the crystal lattice.
• To understand how these interactions contribute to the overall supramolecular architecture.

Main Methods:

• Single-crystal X-ray diffraction was employed to determine the molecular structure.
• Analysis of hydrogen bond donors and acceptors to identify bonding motifs.
• Calculation of distances and angles to characterize inter-species interactions, including π-π stacking.

Main Results:

• The asymmetric unit contains two independent guanidinium cations and quinaldate anions.
• Similar hydrogen-bonding environments, including cyclic motifs (R(2)(2)(8), R(2)(1)(6), R(1)(2)(5)), were observed for both independent cation-anion pairs.
• Weak aromatic ring π-π interactions with a minimum ring-centroid separation of 3.662(2) Å were identified.
• These interactions collectively result in a two-dimensional layered structure.

Conclusions:

• The guanidinium salt of quinaldic acid forms a robust two-dimensional layered structure.
• The crystal packing is governed by a combination of specific hydrogen bonding patterns and π-π stacking interactions.
• The detailed structural analysis provides insights into the supramolecular assembly of organic salts.