5-(1H-Inden-2-yl)-1,3-benzodioxole
Acta Crystallographica. Section E, Structure Reports Online
|January 5, 2011
Summary
Structural analysis of C(16)H(12)O(2) reveals coplanar non-hydrogen atoms. The five-membered ring geometry influences bond angles, and conjugation shortens the inter-ring single bond.
Area of Science:
- Crystallography
- Organic Chemistry
- Molecular Structure
Background:
- Understanding molecular geometry is crucial for predicting chemical properties and reactivity.
- The indenyl moiety is a common structural motif in organic chemistry, influencing electronic and steric properties.
- Conjugation between aromatic systems can significantly alter bond lengths and molecular planarity.
Purpose of the Study:
- To elucidate the detailed molecular structure of the title compound, C(16)H(12)O(2).
- To investigate the influence of the five-membered ring on bond angles and planarity.
- To analyze the effect of conjugation on the single bond linking the two ring systems.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the three-dimensional structure.
- Analysis of atomic coordinates and bond lengths/angles provided insights into molecular geometry.
- Comparison with ideal bond parameters was performed to quantify deviations.
Main Results:
- The non-hydrogen atoms of C(16)H(12)O(2) were found to be coplanar, with a mean r.m.s. deviation of 0.0260(2) Å.
- Deviations in bond angles at the indenyl junction were attributed to the constraints of the five-membered ring.
- The single bond connecting the two ring systems exhibited a length of 1.455(3) Å, significantly shorter than typical single bonds.
Conclusions:
- The molecular structure of C(16)H(12)O(2) is characterized by planarity and specific bond angle distortions due to the indenyl framework.
- Conjugation plays a significant role in shortening the inter-ring single bond, impacting the overall electronic distribution.
- These findings contribute to the understanding of structure-property relationships in conjugated organic molecules.
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