(E)-N'-(2,4,6-Trihydroxy-benzyl-idene)isonicotinohydrazide sesquihydrate

Area of Science:

• Crystallography
• Molecular Chemistry
• Supramolecular Chemistry

Background:

• Understanding the precise arrangement of molecules in solid-state structures is crucial for predicting material properties.
• Hydrogen bonding and π-π stacking are fundamental non-covalent interactions that dictate crystal packing and stability.
• Detailed structural analysis provides insights into molecular recognition and self-assembly processes.

Purpose of the Study:

• To elucidate the crystal structure of the title compound, C(13)H(11)N(3)O(4)·1.5H(2)O.
• To characterize the intra-molecular and inter-molecular interactions present in the crystal lattice.
• To investigate the role of hydrogen bonding and π-π stacking in stabilizing the three-dimensional network.

Main Methods:

• Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
• Analysis of bond distances, angles, and dihedral angles characterized the molecular conformation.
• Hydrogen bond analysis and π-π stacking interactions were identified and quantified.

Main Results:

• The pyridine and benzene rings exhibit a small dihedral angle of 1.50(6)°, indicating near planarity.
• An intra-molecular hydrogen bond forms a six-membered ring (S(6) motif).
• Disordered water molecules and extensive inter-molecular hydrogen bonds (O-H⋯N, O-H⋯O, N-H⋯O, C-H⋯O) create a 3D network.
• A π-π stacking interaction with a centroid-centroid distance of 3.5949(7) Å was observed.

Conclusions:

• The crystal structure is stabilized by a combination of intra- and inter-molecular hydrogen bonds and π-π stacking.
• The observed structural features provide a foundation for understanding the compound's physical and chemical properties.
• This detailed structural characterization contributes to the broader understanding of crystalline materials containing pyridine and benzene moieties.