Developments in benchtop NMR spectroscopy 2015–2020

A mechanistic investigation of the Pd-catalyzed cross-coupling betweenN-tosylhydrazones and aryl halides

“…Benchtop NMR spectrometers do not require liquid helium nor liquid nitrogen to maintain the temperature of the magnet, and the permanent magnets used can be influenced by the local temperature. 241 To ensure reproducibility, the reaction was performed in triplicate using the now-established homogeneous reaction conditions Upon introducing para-substituents on the aryl bromide substrate, maximum rates were subjected to a Hammett analysis (Figure 5.6a). Five substituents with for the oxidative addition step alone.…”

New Algorithm by Maximizing Mutual Information for Correction of Frequency Drifts Arising from One-Dimensional NMR Spectroscopic Data Acquisition

“…Choice (1) gives the frequency shift between the second and third scans, whereas choice (2) gives the frequency shift of the third scans with respect to the "accumulated" spectrum. If the phase shift during the data acquisition is negligible, choice (2) might give a better result because the signal-to-noise ratio in f 1 is higher.…”

“…Benchtop nuclear magnetic resonance (NMR) spectrometers have become increasingly popular during the last decade. 1 These spectrometers utilize compact permanent magnets based on rare-earth metals 2 and have advantages of lower costs (both for installation and maintenance), smaller footprints, and safer operation (no need to use cryogens). Although the capability is limited due to the low operational frequencies, benchtop NMR spectrometers have found many important applications, including natural product analysis, 3 process control, 4 monitoring of bioreactors, 5 health sciences, 6 and education.…”

“…Benchtop nuclear magnetic resonance (NMR) spectrometers have become increasingly popular during the last decade . These spectrometers utilize compact permanent magnets based on rare-earth metals and have advantages of lower costs (both for installation and maintenance), smaller footprints, and safer operation (no need to use cryogens).…”

Predicting Mandarin Fruit Acceptability: From High-Field to Benchtop NMR Spectroscopy

“…However, these systems are generally expensive and have high running and maintenance costs, driving many NMR spectrometer manufacturers to develop smaller and more accessible systems based on cryogen-free permanent magnets. These low-field instruments have magnetic fields below 2.3 T (i.e., 1 H resonance frequencies under 100 MHz), fit on a regular laboratory benchtop, and are even suitable for use in field experiments [ 2 , 3 ]. The basis of these instruments is the use of rare-earth ring-shaped magnets that produce relatively strong and homogeneous fields [ 3 ].…”