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Updated: Jun 1, 2026
12:07
Microwave-assisted Intramolecular Dehydrogenative Diels-Alder Reactions for the Synthesis of Functionalized Naphthalenes/Solvatochromic Dyes
Published on: April 1, 2013
(2,7-Dimeth-oxy-naphthalen-1-yl)(phen-yl)methanone
Yuichi Kato1, Atsushi Nagasawa, Daichi Hijikata
1Department of Organic and Polymer Materials Chemistry, Tokyo University of Agriculture & Technology, Koganei, Tokyo 184-8588, Japan.
Summary
This study reveals three distinct molecular shapes (conformers) for a compound C(19)H(16)O(3). These conformers exhibit non-planar aromatic rings, with specific dihedral angles influencing their crystal structure stabilized by hydrogen bonds.
Area of Science:
- Organic Chemistry
- Crystallography
- Molecular Structure
Background:
- Understanding molecular conformation is crucial in organic chemistry.
- Aromatic ring systems exhibit diverse spatial arrangements.
- Crystal structure analysis provides insights into intermolecular forces.
Purpose of the Study:
- To characterize the crystal structure of the compound C(19)H(16)O(3).
- To identify and describe the independent conformers present in the asymmetric unit.
- To analyze the spatial arrangement of aromatic rings and intermolecular interactions.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the crystal structure.
- Analysis of the asymmetric unit revealed the presence of three independent conformers.
- Dihedral angles between aromatic ring systems were precisely measured.
Main Results:
- The asymmetric unit contains three distinct conformers of C(19)H(16)O(3).
- All conformers display non-coplanar aromatic rings, with the aroyl group significantly twisted relative to the naphthalene core.
- Measured dihedral angles range from 75.34(7)° to 86.47(7)°, indicating near-perpendicular orientations.
Conclusions:
- The compound C(19)H(16)O(3) exists in multiple distinct conformations in the solid state.
- The observed non-planar aromatic ring structures are a key feature of these conformers.
- Intermolecular C-H⋯O hydrogen bonds play a significant role in stabilizing the crystal packing.
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