3-Iodobenzaldehyde: XRD, FT-IR, Raman and DFT studies
Chandraju Sadolalu Chidan Kumar1, Cemal Parlak2, Mahir Tursun2
1X-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia; Department of Engineering Chemistry, Alva's Institute of Engineering & Technology, Mijar, Modbidri, 574225, Karnataka, India.
Summary
This study characterizes 3-iodobenzaldehyde structure using spectroscopy and X-ray diffraction. Computational analysis reveals conformational preferences and halogen effects in related compounds, showing fluorine
Area of Science:
- Molecular Spectroscopy
- Crystallography
- Computational Chemistry
Background:
- Understanding the structure and properties of halogenated benzaldehydes is crucial for various chemical applications.
- 3-iodobenzaldehyde (3IB) serves as a model compound for studying halogen effects on molecular conformation and vibrational properties.
Purpose of the Study:
- To characterize the molecular structure and vibrational properties of 3-iodobenzaldehyde (3IB).
- To investigate the conformational preferences and halogen effects in 3-halogenobenzaldehydes using theoretical methods.
Main Methods:
- Experimental characterization using Fourier-transform infrared (FT-IR) spectroscopy, Raman spectroscopy, and single-crystal X-ray diffraction.
- Theoretical calculations employing density functional theory (DFT) with B3LYP functional and appropriate basis sets.
- Conformational analysis, geometric parameter optimization, normal mode frequency calculations, and potential energy distribution (PED) analysis.
Main Results:
- 3-iodobenzaldehyde crystallizes in the monoclinic space group P21/c, adopting the O-trans conformation.
- Excellent agreement was found between experimental and theoretically predicted structural parameters and vibrational frequencies.
- Theoretical studies on 3-halogenobenzaldehydes revealed a small free energy difference between isomers and a rotational barrier of approximately 8 kcal/mol.
- An atypical conformational preference influenced by fluorine was observed.
Conclusions:
- The study successfully elucidated the structure and vibrational characteristics of 3-iodobenzaldehyde.
- The findings provide insights into the impact of halogens on the conformational behavior of benzaldehyde derivatives.
- The observed atypical fluorine behavior highlights the complexity of halogen effects in organic molecules.
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