Propane-1,3-diyl bis-(pyridine-4-carboxyl-ate)
Summary
This study details the gauche-gauche conformation of a novel compound, C(15)H(14)N(2)O(4), revealing its structural similarities and differences compared to a positional isomer. Crystal structure analysis highlights key conformational variations and stabilization through hydrogen bonding.
Area of Science:
- Crystallography
- Organic Chemistry
- Molecular Structure
Background:
- The title compound, C(15)H(14)N(2)O(4) (I), is a positional isomer of propane-1,3-diyl bis-(pyridine-3-carboxylate) (II).
- Understanding molecular conformation is crucial for predicting chemical and physical properties.
Purpose of the Study:
- To elucidate the crystal structure and conformation of compound (I).
- To compare the geometric parameters and conformational differences between compound (I) and its positional isomer (II).
Main Methods:
- Single-crystal X-ray diffraction analysis was employed to determine the molecular and crystal structure of compound (I).
- Geometric parameters, including torsion and dihedral angles, were analyzed and compared between the two compounds.
Main Results:
- Compound (I) adopts a gauche-gauche (GG) conformation and possesses a twofold rotation axis.
- Excellent agreement in overall geometric parameters was observed between compounds (I) and (II).
- Significant differences were noted in O/C/C/C-O/C/C/C torsion angles and the dihedral angle between aromatic rings.
Conclusions:
- The crystal structure of compound (I) is stabilized by weak C-H⋯N and C-H⋯O hydrogen bonding.
- The conformational analysis provides valuable insights into the structure-property relationships of pyridine carboxylate esters.
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