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06:46
Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
(E)-6-Methyl-3-(2-methyl-benzyl-idene)-chroman-2-one
Acta Crystallographica. Section E, Structure Reports Online
|March 14, 2012
Summary
This study details the molecular structure of a C18H16O2 compound, revealing a distorted screw-boat conformation in its heterocyclic ring. Crystal packing analysis identified specific hydrogen bonds and interactions influencing molecular arrangement.
Area of Science:
- Organic Chemistry
- Crystallography
- Molecular Structure
Background:
- The chroman-2-one scaffold is a core structure in various biologically active compounds.
- Understanding the conformational flexibility and crystal packing of such molecules is crucial for structure-activity relationship studies.
Purpose of the Study:
- To elucidate the precise three-dimensional molecular structure of the title compound, C18H16O2.
- To analyze the conformational preferences of the chroman-2-one heterocyclic ring.
- To investigate the intermolecular interactions governing crystal packing.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
- Analysis of bond lengths, bond angles, and dihedral angles provided conformational insights.
- Crystal structure was examined for intermolecular interactions, including hydrogen bonding and pi-pi stacking.
Main Results:
- The title compound, C18H16O2, exhibits a slightly distorted screw-boat conformation for its heterocyclic chroman-2-one ring.
- A significant dihedral angle of 67.5(1)° was measured between the coumarin and benzene ring systems.
- Crystal packing is characterized by the formation of centrosymmetric R(2) (2)(8) dimers through C-H⋯O hydrogen bonds and additional C-H⋯π interactions.
Conclusions:
- The study provides a detailed structural characterization of a specific C18H16O2 derivative.
- The observed conformation and crystal packing highlight the interplay of intramolecular and intermolecular forces in dictating molecular architecture.
- These findings contribute to the understanding of structure-property relationships in chroman-2-one based systems.
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