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Updated: May 31, 2026
09:45
Modification and Functionalization of the Guanidine Group by Tailor-made Precursors
Published on: April 27, 2017
3-(Pyridin-4-yl-thio)-pentane-2,4-dione
Qing-Fu Zhang1, Jian-Dong Pang, De-Zhi Sun
1College of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, People's Republic of China.
Summary
The crystal structure of a novel compound reveals the acetyl-acetone group in a keto form, exhibiting near planarity. An intramolecular hydrogen bond forms a stable six-membered ring within the molecule.
Area of Science:
- Crystallography
- Organic Chemistry
- Molecular Structure
Background:
- Understanding the three-dimensional arrangement of atoms in organic molecules is crucial for predicting their properties and reactivity.
- The keto-enol tautomerism of acetyl-acetone and its coordination chemistry are well-studied areas.
- Pyridine derivatives are important scaffolds in medicinal chemistry and materials science.
Purpose of the Study:
- To elucidate the detailed crystal structure of the title compound, C(10)H(11)NO(2)S.
- To analyze the conformation and planarity of the acetyl-acetone moiety within the crystal lattice.
- To investigate the presence and geometry of intramolecular hydrogen bonding.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the molecular structure.
- Crystallographic data were collected and refined to obtain precise atomic coordinates.
- Geometric analyses, including dihedral angles and bond distances/angles, were performed.
Main Results:
- The acetyl-acetone group was confirmed to be in the keto form and displayed approximate planarity of its non-hydrogen atoms (maximum deviation of 0.055 Å).
- A significant dihedral angle of 85.90° was observed between the acetyl-acetone group and the pyridine ring.
- An intramolecular O-H⋯O hydrogen bond was identified, forming a six-membered ring involving the acetyl-acetone group.
Conclusions:
- The crystal structure provides definitive insights into the molecular conformation and bonding in this specific pyridine derivative.
- The observed planarity and hydrogen bonding suggest a degree of electronic delocalization and stabilization within the acetyl-acetone moiety.
- These structural findings contribute to the broader understanding of structure-property relationships in related organic compounds.
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