Online monitoring of transesterification reaction by medium-resolution benchtop 1H NMR and NIR spectroscopy

Quantitative reaction monitoring using parahydrogen-enhanced benchtop NMR spectroscopy

“…Several studies have validated the use of benchtop NMR spectrometers for reaction monitoring through comparisons to other time-resolved techniques, such as high-field NMR, gas chromatography 33 and IR spectroscopy. 34 Similar studies have also highlighted the benefit of using benchtop NMR with complementary on-line reaction monitoring techniques, such as IR [35][36][37] and mass spectrometry, 38 in order to maximise the information gained about a reaction system.…”

“…[22][23][24][25][26] In recent years, continued methods development on benchtop NMR systems has enabled expansion into reaction monitoring using heteronuclear channels 27,28 and also using multidimensional NMR (both with standard 29,30 and ultra-fast 31,32 the use of benchtop NMR spectrometers for reaction monitoring through comparisons to other time-resolved techniques, such as high-field NMR, gas chromatography 33 and IR spectroscopy. 34 Similar studies have also highlighted the benefit of using benchtop NMR with complementary on-line reaction monitoring techniques, such as IR [35][36][37] and mass spectrometry, 38 in order to maximise the information gained about a reaction system. The transition to a weaker magnetic field strength can lead to challenges both in terms of sensitivity and chemical shift dispersion.…”

Polarization transfer methods for quantitative analysis of flowing mixtures with benchtop 13C NMR spectroscopy

“…Benchtop NMR spectrometers have already been used in research to monitor a variety of reactions and processes, highlighting the promising prospects for future use in industrial applications. [18][19][20][21][22][23][24][25][26][27][28][29] However, the relatively low magnetic field strength of benchtop NMR spectrometers results in low spectral resolution, even at field strengths of up to 2.5 T that have become available recently. The resulting peak overlap, especially in combination with peak splitting, impedes the quantitative analysis of mixtures by 1 H NMR spectroscopy.…”

“…The spectrometers are therefore compact, comparatively inexpensive to purchase and to maintain, and easy to operate. Benchtop NMR spectrometers have already been used in research to monitor a variety of reactions and processes, highlighting the promising prospects for future use in industrial applications 18–29 …”