1H-Indole-3-carbaldehyde azine.

Area of Science:

• Crystallography
• Organic Chemistry
• Materials Science

Background:

• Understanding the three-dimensional structure of organic molecules is crucial for predicting their properties and applications.
• Intermolecular interactions, such as hydrogen bonding, dictate crystal packing and influence bulk material characteristics.
• The specific arrangement of atoms within a crystal lattice affects electronic, optical, and mechanical behaviors.

Purpose of the Study:

• To elucidate the crystal structure of the title compound, C18H14N4.
• To analyze the molecular geometry, including planarity and bond configurations.
• To investigate the intermolecular interactions responsible for the observed crystal packing.

Main Methods:

• Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
• Crystallographic data were analyzed to identify symmetry elements, bond lengths, bond angles, and dihedral angles.
• Intermolecular interactions, specifically hydrogen bonds, were identified and characterized.

Main Results:

• The molecule C18H14N4 crystallizes with a half-molecule in the asymmetric unit, located on a center of inversion.
• A trans configuration of the N-N single bond was observed.
• The indole fused-ring system and the -CH=N-N=CH- fragment exhibit near-coplanarity, with a dihedral angle of 9.8(2)°.
• Adjacent molecules are connected via indole-azine N-H⋯N hydrogen bonds, forming a layered motif.

Conclusions:

• The crystal structure of C18H14N4 is characterized by a specific molecular geometry and a layered arrangement driven by hydrogen bonding.
• The near-planarity of the molecule suggests potential for pi-stacking interactions, although hydrogen bonding dominates the observed packing.
• These findings contribute to the understanding of structure-property relationships in organic crystalline materials.