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Updated: Jun 1, 2026
06:46
Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
(1E,4E)-1,5-Bis(2,4,5-trimethoxy-phen-yl)penta-1,4-dien-3-one
Summary
This study analyzes the crystal structure of C(23)H(26)O(7), detailing molecular conformations and weak intermolecular interactions. The research reveals specific dihedral angles and the formation of a 3D network through C-H⋯O and C-H⋯π interactions.
Area of Science:
- Crystallography
- Chemical Physics
- Materials Science
Background:
- Understanding molecular structure and intermolecular forces is crucial for predicting material properties.
- The title compound, C(23)H(26)O(7), presents an interesting case for crystallographic analysis due to its potential for complex molecular arrangements.
- Previous studies on similar organic molecules highlight the importance of weak interactions in crystal packing.
Purpose of the Study:
- To determine the precise three-dimensional crystal structure of C(23)H(26)O(7).
- To quantify the dihedral angles between aromatic rings and the central enone fragment.
- To identify and characterize the intermolecular interactions governing crystal assembly.
Main Methods:
- Single-crystal X-ray diffraction was employed to collect diffraction data.
- The crystal structure was solved and refined using standard crystallographic software.
- Analysis of bond lengths, bond angles, and intermolecular contacts was performed.
Main Results:
- The asymmetric unit contains three molecules of C(23)H(26)O(7).
- Dihedral angles between benzene rings range from 4.34° to 18.11°, and angles with the penta-1,4-dien-3-one core vary across the molecules.
- Intermolecular C-H⋯O and C-H⋯π interactions link molecules into a 3D network, with observed π-π interactions at distances of 3.5984 Å and 3.5545 Å.
Conclusions:
- The crystal structure of C(23)H(26)O(7) is characterized by significant conformational flexibility and specific dihedral angles.
- Weak intermolecular forces, including C-H⋯O, C-H⋯π, and π-π interactions, play a key role in stabilizing the observed three-dimensional crystal lattice.
- These findings contribute to the understanding of structure-property relationships in organic crystalline materials.
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