3,5-Dimethyl-4-nitroso-1H-pyrazole

Area of Science:

• Crystallography
• Molecular structure analysis
• Hydrogen bonding

Background:

• Understanding molecular conformations is crucial in chemistry and materials science.
• Pyrazole derivatives are important in various chemical applications.
• Oxime functional groups exhibit diverse chemical properties.

Purpose of the Study:

• To elucidate the crystal structure and conformational characteristics of the title compound, C(5)H(7)N(3)O.
• To investigate the hydrogen bonding network and its influence on molecular arrangement.
• To analyze the geometric parameters and electronic state of the oxime group within the crystal lattice.

Main Methods:

• Single-crystal X-ray diffraction was employed to determine the unit cell and molecular structure.
• Conformational analysis was performed to identify and differentiate molecular arrangements.
• Intermolecular interactions, specifically hydrogen bonds, were analyzed to understand crystal packing.

Main Results:

• Two distinct conformers (A and B) were identified within the unit cell, differing in the orientation of the oxime group relative to the pyrazole nitrogen.
• The oxime group was confirmed to exist in the nitroso tautomeric form in both conformers.
• Molecules self-assemble into zigzag-like chains along the b-axis through intermolecular N-H⋯O and N-H⋯N hydrogen bonds.

Conclusions:

• The crystal structure of C(5)H(7)N(3)O is characterized by the presence of two conformers with distinct geometric parameters.
• The hydrogen bonding network plays a significant role in organizing these molecules into extended chain structures.
• The nitroso form of the oxime group is stable within this crystalline environment.