2-Phenyl-4,5-di-p-tolyl-1H-imidazol-3-ium picrate

Area of Science:

• Crystallography
• Supramolecular Chemistry
• Organic Synthesis

Background:

• Molecular salts are formed by the transfer of a proton from an acidic component to a basic component.
• Imidazole derivatives are versatile organic compounds with applications in various fields.
• Picric acid is a strong organic acid known for its explosive properties and use in chemical analysis.

Purpose of the Study:

• To synthesize and characterize a novel molecular salt composed of a substituted imidazole and picric acid.
• To elucidate the structural features and intermolecular interactions within the synthesized molecular salt.
• To confirm the occurrence of proton transfer between the constituent molecules.

Main Methods:

• Slow solvent evaporation method using ethanol as the solvent.
• Single-crystal X-ray diffraction analysis to determine the crystal structure.
• Analysis of hydrogen bonding interactions (N-H⋯O and C-H⋯O) within the crystal lattice.

Main Results:

• Successful synthesis of the molecular salt: 4,5-bis(4-methylphenyl)-2-phenyl-1H-imidazol-3-ium 2,4,6-trinitrobenzen-1-olate.
• Crystallization in the monoclinic space group P21.
• Confirmation of proton transfer from picric acid to the imidazole nitrogen atom.
• Identification of extensive N-H⋯O and C-H⋯O hydrogen bonding networks stabilizing the crystal structure.

Conclusions:

• The synthesized molecular salt exhibits a clear proton transfer from picric acid to the imidazole ring.
• The crystal structure is stabilized by a robust network of hydrogen bonds, highlighting supramolecular assembly principles.
• This study contributes to the understanding of acid-base interactions and crystal engineering in molecular salt formation.