Crystal structure of 1,3-bis-{[4-(acetyl-sulfanyl)phenyl]ethynyl}azulene

Area of Science:

• Crystallography
• Organic Chemistry
• Materials Science

Background:

• Azulene derivatives are of interest due to their unique electronic properties.
• Understanding molecular packing is crucial for predicting material behavior.
• Sulfur-containing organic molecules can exhibit diverse intermolecular interactions.

Purpose of the Study:

• To elucidate the crystal structure of the title compound (C30H20O2S2).
• To analyze the dihedral angles between the azulene core, pendant benzene rings, and acetyl-sulfanyl groups.
• To investigate the intermolecular interactions governing the crystal packing.

Main Methods:

• Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
• Analysis of bond lengths, bond angles, and dihedral angles.
• Identification and characterization of intermolecular interactions, including hydrogen bonds and π-π stacking.

Main Results:

• The crystal structure of C30H20O2S2 was determined, revealing specific dihedral angles: 28.96° and 55.15° between the azulene core and benzene rings, and 59.60° and 84.79° between benzene rings and acetyl-sulfanyl groups.
• Absence of expected π-π stacking interactions was observed.
• Molecular packing is dominated by C-H⋯O hydrogen bonds, forming C(12) chains, further supported by weak C-H⋯π contacts.

Conclusions:

• The crystal structure of the C30H20O2S2 compound is characterized by specific dihedral angles and an unusual packing motif.
• Intermolecular interactions are primarily driven by C-H⋯O hydrogen bonds, leading to chain formation, rather than π-π stacking.
• This detailed structural analysis provides insights into the solid-state behavior of azulene derivatives with acetyl-sulfanyl substituents.