Self-assembly structures of 1H-indazoles in the solution and solid phases: a vibrational (IR, FIR, Raman, and VCD)
J R Avilés Moreno1, M M Quesada Moreno, J J López González
1Departamento de Química Física y Analítica, Universidad de Jaén, Campus Las Lagunillas, 23071 Jaén (Spain).
Summary
1H-indazoles exhibit complex molecular associations, forming dimers, trimers, or catemers. This study introduces a strategy using vibrational spectroscopy and quantum calculations to identify these structures across different phases.
Area of Science:
- Chemical Crystallography
- Molecular Spectroscopy
- Chirality Studies
Background:
- 1H-indazoles are valuable for studying molecular association and chiral compound resolution.
- Their ability to crystallize as dimers, trimers, or catemers complicates experimental structural analysis.
- Understanding structural polymorphism in different phases is crucial.
Purpose of the Study:
- To address the challenge of identifying diverse 1H-indazole structures in various phases.
- To investigate the simultaneous presence of different structures within a single phase.
- To develop a comprehensive method for determining these structures.
Main Methods:
- Utilizing vibrational circular dichroism (VCD) spectroscopy, which is sensitive to chirality.
- Employing non-chiral vibrational techniques: infrared (IR), far-infrared (FIR), and Raman spectroscopy.
- Integrating quantum chemical calculations to support experimental data.
Main Results:
- A multi-technique strategy was successfully outlined for analyzing 1H-indazole structures.
- The study provides a framework for differentiating and identifying various crystalline forms.
- Vibrational spectroscopy combined with computational methods offers robust structural insights.
Conclusions:
- The proposed strategy effectively tackles the complexity of 1H-indazole polymorphism.
- It enables the determination of molecular structures and their associations across different phases.
- This approach advances the understanding of molecular self-assembly in chiral systems.
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