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Updated: Jun 1, 2026

Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid
Published on: November 15, 2017
Dimethyl 4,4'-(pyridine-2,6-diyl)dibenzoate.
Yue Cui1, Qian Gao, Huan-Huan Wang
1College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, People's Republic of China.
This study details the molecular structure of C(21)H(17)NO(4), revealing its dish-like shape and axial symmetry. The arrangement of its benzene and pyridine rings was precisely determined through crystallographic analysis.
Area of Science:
- Crystallography
- Molecular structure determination
- Organic chemistry
Background:
- Understanding molecular geometry is crucial in chemistry.
- C(21)H(17)NO(4) is a molecule of interest for its structural properties.
Purpose of the Study:
- To elucidate the three-dimensional structure of the title molecule, C(21)H(17)NO(4).
- To analyze the symmetry and dihedral angles within the molecule.
Main Methods:
- Single-crystal X-ray diffraction was employed.
- Crystallographic data was collected and analyzed to determine atomic positions and bond angles.
Main Results:
- The molecule C(21)H(17)NO(4) exhibits axial symmetry with the nitrogen atom on a twofold axis.
- A dish-shaped conformation was observed, with specific dihedral angles between the aromatic rings (24.643(1)° and 24.797(1)°).
- The carboxylate group (-COO) plane is nearly coplanar with the benzene ring (dihedral angle = 5.286(1)°).
Conclusions:
- The crystallographic analysis provides precise structural data for C(21)H(17)NO(4).
- The observed molecular geometry and symmetry offer insights into the molecule's potential properties and interactions.
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