Two (E)-2-({[4-(dialkylamino)phenyl]imino}methyl)-4-nitrophenols
Arto Valkonen1, Erkki Kolehmainen, Aleksandra Grzegórska
1Department of Chemistry, University of Jyväskylä, Finland. arto.m.valkonen@jyu.fi
Summary
Slow evaporation of NMR samples yielded two N-salicylideneaniline crystals with different packing. Despite minor structural changes, these compounds exhibit distinct space groups and molecular arrangements, highlighting subtle structure-property relationships.
Area of Science:
- Crystallography
- Organic Chemistry
- Solid-State Chemistry
Background:
- N-salicylideneaniline derivatives are known for their diverse structural and electronic properties.
- Understanding molecular packing is crucial for predicting material characteristics.
Purpose of the Study:
- To synthesize and characterize two N-salicylideneaniline derivatives with subtle structural variations.
- To investigate the impact of minor structural differences on crystal packing and molecular arrangement.
Main Methods:
- Slow evaporation of analytical Nuclear Magnetic Resonance (NMR) samples.
- Single-crystal X-ray diffraction to determine crystal structures and molecular packing.
Main Results:
- Crystallization of (E)-2-({[4-(dimethylamino)phenyl]imino}methyl)-4-nitrophenol (I) and (E)-2-({[4-(diethylamino)phenyl]imino}methyl)-4-nitrophenol (II).
- Compounds (I) and (II) adopted different space groups and exhibited distinct molecular packing arrangements.
- Intramolecular O-H···N hydrogen bonds contributed to near-planarity in both molecules.
- The dihedral angles between the aromatic rings were 13.44 (19)° for (I) and 2.57 (8)° for (II).
- Weak intermolecular interactions, including π-π stacking and C-H···O bonds, were observed.
Conclusions:
- Minor structural modifications in N-salicylideneaniline derivatives can lead to significant differences in crystal packing and space group.
- The observed packing variations are attributed to subtle changes in intermolecular forces and molecular conformation.
- This study provides insights into structure-property relationships in crystalline organic materials.
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