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NMR Reaction Monitoring Robust to Spectral Distortions
Barbara Domżał1, Magdalena Grochowska-Tatarczak2, Przemysław Malinowski2
1Faculty of Mathematics, Informatics and Mechanics, University of Warsaw, Banacha 2, Warsaw 02-097, Poland.
Analytical Chemistry
|July 16, 2025
Summary
This study introduces a new method using Wasserstein distance for analyzing distorted Nuclear Magnetic Resonance (NMR) spectra from chemical reactions. The open-source software enables accurate quantification of reaction components even with poor spectral quality.
Area of Science:
- Analytical Chemistry
- Spectroscopy
- Chemical Kinetics
Background:
- Nuclear Magnetic Resonance (NMR) spectroscopy is vital for molecular structure determination and reaction monitoring.
- Standard NMR analysis faces challenges with distorted spectra due to sample inhomogeneity and fast reactions.
- Non-deuterated solvents prevent magnetic field stabilization, further degrading spectral quality.
Purpose of the Study:
- To develop a novel approach for quantitative analysis of distorted NMR spectra.
- To overcome limitations of standard software in analyzing low-quality NMR data.
- To provide an accessible tool for reaction monitoring under challenging conditions.
Main Methods:
- Utilized Wasserstein distance for spectral analysis.
- Developed an open-source software tool for quantitative component analysis.
- Applied the method to a series of time-indexed NMR spectra.
Main Results:
- Successfully quantified reaction mixture components from distorted spectra.
- Demonstrated effective analysis without the need for traditional peak-picking.
- The method is robust against spectral distortions like inhomogeneous line shapes and varying peak positions.
Conclusions:
- The proposed Wasserstein distance-based method offers a new paradigm for quantitative NMR analysis.
- The open-source software provides a user-friendly solution for analyzing challenging NMR datasets.
- This approach enhances the utility of NMR spectroscopy for monitoring complex chemical reactions.
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