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Updated: May 11, 2026
05:07
Microwave-Assisted Preparation of 1-Aryl-1H-pyrazole-5-amines
Published on: June 23, 2019
3-Methyl-1,5-diphenyl-4,5-dihydro-1H-pyrazole
M Manjula1, P Jayaroopa, B C Manjunath
1Department of Studies in Physics, Manasagangotri, University of Mysore, Mysore 570 006, India.
Summary
The crystal structure of C16H16N2 reveals a dihydro-pyrazole ring with a shallow envelope conformation. This study details the specific atomic displacements and dihedral angles within this heterocyclic compound.
Area of Science:
- Organic Chemistry
- Crystallography
Background:
- Dihydro-pyrazole derivatives are important heterocyclic compounds.
- Understanding their three-dimensional structure is crucial for predicting chemical properties and reactivity.
Purpose of the Study:
- To determine the precise molecular structure of the title compound (C16H16N2) using X-ray crystallography.
- To analyze the conformation of the dihydro-pyrazole ring and the orientation of the phenyl substituent.
Main Methods:
- Single-crystal X-ray diffraction was employed to collect diffraction data.
- The crystal structure was solved and refined to determine atomic positions and bond parameters.
Main Results:
- The dihydro-pyrazole ring was found to adopt a shallow envelope conformation.
- The carbon atom bearing the phenyl group exhibited a displacement of 0.298(2) Å from the ring plane.
- Specific dihedral angles were measured between the ring and the phenyl groups (13.49(13)° and 82.22(16)°).
Conclusions:
- The study provides detailed structural information for C16H16N2.
- The observed conformation and substituent orientation offer insights into the stereochemistry of dihydro-pyrazoles.
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