Two phosphate-imidazole complexes with and without a hydrogen-bonded guest molecule

Area of Science:

• Crystal Engineering
• Supramolecular Chemistry
• Organic Chemistry

Background:

• Understanding molecular interactions is crucial for designing functional materials.
• Hydrogen bonding plays a significant role in the self-assembly of molecular structures.
• Thiodiphenyl phosphate complexes offer a platform for studying diverse supramolecular architectures.

Purpose of the Study:

• To elucidate the crystal structures of two novel imidazolium thiodiphenyl phosphate complexes.
• To investigate the influence of solvent molecules on hydrogen bonding patterns in these complexes.
• To analyze the specific hydrogen bonding interactions, including N-H...O and C-H...O bonds.

Main Methods:

• Single-crystal X-ray diffraction was employed to determine the molecular structures.
• Analysis of hydrogen bond distances and angles.
• Comparison of crystal packing in the absence and presence of a hydrazine solvent molecule.

Main Results:

• The structure of complex (I) revealed a typical hydrogen-bonded chain formed by imidazolium cations and thiodiphenyl phosphate anions.
• In complex (II), a diisopropyl hydrazodicarboxylate solvent molecule was found to insert into the hydrogen-bonded chain.
• Complex (I) displayed a strong N-H...O hydrogen bond (2.603 Å), while complex (II) showed bifurcated hydrogen bonds involving the hydrazine molecule and a C-H...O interaction.

Conclusions:

• The presence of a substituted hydrazine solvent molecule significantly alters the supramolecular assembly of thiodiphenyl phosphate complexes.
• Hydrogen bonding interactions, including bifurcated and C-H...O bonds, dictate the crystal packing and structural diversity.
• This research provides insights into the role of solvent molecules in controlling crystal structures and hydrogen bonding networks.