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Maschmeyer T, Russell DJ, Napolitano JG, Hein JE. Reaction monitoring via benchtop nuclear magnetic resonance spectroscopy: A practical comparison of on-line stopped-flow and continuous-flow sampling methods. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:310-322. [PMID: 37737536 DOI: 10.1002/mrc.5395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 08/28/2023] [Accepted: 08/30/2023] [Indexed: 09/23/2023]
Abstract
The ability for nuclear magnetic resonance (NMR) spectroscopy to provide quantitative, structurally rich information makes this spectroscopic technique an attractive reaction monitoring tool. The practicality of NMR for this type of analysis has only increased in the recent years with the influx of commercially available benchtop NMR instruments and compatible flow systems. In this study, we aim to compare 19F NMR reaction profiles acquired under both on-line continuous-flow and stopped-flow sampling methods, with modern benchtop NMR instrumentation, and two reaction systems: a homogeneous imination reaction and a biphasic activation of a carboxylic acid to acyl fluoride. Reaction trends with higher data density can be acquired with on-line continuous-flow analyses, and this work highlights that representative reaction trends can be acquired without any correction when monitoring resonances with a shorter spin-lattice relaxation time (T1), and with the used flow conditions. On-line stopped-flow analyses resulted in representative reaction trends in all cases, including the monitoring of resonances with a long T1, without the need of any correction factors. The benefit of easier data analysis, however, comes with the cost of time, as the fresh reaction solution must be flowed into the NMR system, halted, and time must be provided for spins to become polarized in the instrument's external magnetic field prior to spectral measurement. Results for one of the reactions were additionally compared with the use of a high-field NMR.
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Affiliation(s)
- Tristan Maschmeyer
- Department of Chemistry, The University of British Columbia, Vancouver, Canada
- Small Molecule Pharmaceutical Sciences, Genentech Inc., South San Francisco, California, USA
| | - David J Russell
- Small Molecule Pharmaceutical Sciences, Genentech Inc., South San Francisco, California, USA
| | - José G Napolitano
- Small Molecule Pharmaceutical Sciences, Genentech Inc., South San Francisco, California, USA
| | - Jason E Hein
- Department of Chemistry, The University of British Columbia, Vancouver, Canada
- Acceleration Consortium, University of Toronto, Toronto, Canada
- Department of Chemistry, University of Bergen, Bergen, Norway
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2
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Sarkar A, Dong G, Quaglia-Motta J, Sackett K. Flow-NMR as a Process-Monitoring Tool for mRNA IVT Reaction. J Pharm Sci 2024; 113:900-905. [PMID: 38008177 DOI: 10.1016/j.xphs.2023.11.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 11/08/2023] [Accepted: 11/21/2023] [Indexed: 11/28/2023]
Abstract
Messenger RNA (mRNA) based vaccines were instrumental in accelerating the end of the SARS-CoV-2 pandemic and are being aggressively developed as prophylaxes for a range of viral diseases. The swift adoption of mRNA-based therapeutics has also left open vast areas of opportunity for improving the development of mRNA-based drugs. One such area with immense potential focuses on the mRNA drug substance production, where mRNA is generated by a cell-free reaction called in vitro transcription (IVT). Process analytical technologies (PAT) are integral to the pharmaceutical industry and are necessary to facilitate agile process optimization and enhance process quality, control, and understanding. Due to the complexity and novelty inherent to the IVT reaction, there is a need for effective PAT that would provide in-depth, real-time insight into the reaction process to allow delivery of novel mRNA vaccines to patients faster in a more cost-effective way. Herein, we showcase the development of flow-nuclear magnetic resonance (flow-NMR) as a highly effective process-analytical tool for monitoring mRNA IVT reactions to support process development, optimization, and production.
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Affiliation(s)
- Aritra Sarkar
- Analytical Research and Development, Pfizer Research and Development, Eastern Point Road, Groton, CT 06340, United States of America.
| | - Guogang Dong
- Bioprocess Research and Development, Pfizer Research and Development, 1 Burtt Road, Andover, Massachusetts 01810, United States of America
| | - Jennifer Quaglia-Motta
- Bioprocess Research and Development, Pfizer Research and Development, 1 Burtt Road, Andover, Massachusetts 01810, United States of America
| | - Kelly Sackett
- Analytical Research and Development, Pfizer Research and Development, Eastern Point Road, Groton, CT 06340, United States of America.
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3
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Sulzer N, Polterauer D, Hone CA, Kappe CO. Preparation of Sulfonyl Chlorides by Oxidative Chlorination of Thiols and Disulfides using HNO 3/HCl/O 2 in a Flow Reactor. CHEMSUSCHEM 2024:e202400292. [PMID: 38477977 DOI: 10.1002/cssc.202400292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 03/07/2024] [Accepted: 03/08/2024] [Indexed: 03/14/2024]
Abstract
A continuous flow metal-free protocol for the synthesis of sulfonyl chlorides from thiols and disulfides in the presence of nitric acid, hydrochloric acid and oxygen was developed. The influence of the reaction parameters was investigated under batch and flow conditions. Online 19F NMR was successfully implemented to investigate different reaction conditions within a single experiment. The sulfonyl chlorides were isolated (mostly in 70-81 % yield) after performing a simple aqueous washing procedure. In particular, the protocol was successfully operated for >6 hours to convert diphenyl disulfide to its corresponding sulfonyl chloride, achieving a throughput of 3.7 g h-1. The environmental impact of the protocol was assessed and compared to an existing continuous flow protocol using 1,3-dichloro-5,5-dimethylhydantoin (DCH) as reagent. The process mass intensity (PMI) for the newly-developed flow protocol (15) compared favorably to the DCH flow process (20).
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Affiliation(s)
- Niklas Sulzer
- Center for Continuous Flow Synthesis and Processing (CCLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010, Graz, Austria
- Institute of Chemistry, University of Graz, Heinrichstrasse 28, 8010, Graz, Austria
| | - Dominik Polterauer
- Center for Continuous Flow Synthesis and Processing (CCLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010, Graz, Austria
- Institute of Chemistry, University of Graz, Heinrichstrasse 28, 8010, Graz, Austria
| | - Christopher A Hone
- Center for Continuous Flow Synthesis and Processing (CCLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010, Graz, Austria
- Institute of Chemistry, University of Graz, Heinrichstrasse 28, 8010, Graz, Austria
| | - C Oliver Kappe
- Center for Continuous Flow Synthesis and Processing (CCLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010, Graz, Austria
- Institute of Chemistry, University of Graz, Heinrichstrasse 28, 8010, Graz, Austria
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4
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Lhoste C, Bazzoni M, Bonnet J, Bernard A, Felpin FX, Giraudeau P, Dumez JN. Broadband ultrafast 2D NMR spectroscopy for online monitoring in continuous flow. Analyst 2023; 148:5255-5261. [PMID: 37740277 DOI: 10.1039/d3an01165h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/24/2023]
Abstract
Flow NMR is a powerful tool to monitor chemical reactions under realistic conditions. Here, we describe ultrafast (UF) 2D NMR schemes that make it possible to acquire broadband homonuclear 2D NMR spectra in 90 seconds or less for a continuously flowing sample. An interleaved acquisition strategy is used to address the spectral width limitation of UF 2D NMR. We show how, for a flowing sample, the use of a transverse axis for spatial encoding makes it possible to achieve the very high scan-to-scan stability required for interleaved acquisition. We also describe an optimised solvent suppression strategy that is effective for interleaved acquisition in continuous flow. These developments open the way to online monitoring with flow 2D NMR at high time resolution, as we illustrate with the monitoring of an organocatalysed condensation reaction.
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Affiliation(s)
- Célia Lhoste
- Nantes Université, CNRS, CEISAM UMR6230, F-44000 Nantes, France.
| | | | - Justine Bonnet
- Nantes Université, CNRS, CEISAM UMR6230, F-44000 Nantes, France.
| | - Aurélie Bernard
- Nantes Université, CNRS, CEISAM UMR6230, F-44000 Nantes, France.
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Bara‐Estaún A, Harder MC, Lyall CL, Lowe JP, Suturina E, Hintermair U. Paramagnetic Relaxation Agents for Enhancing Temporal Resolution and Sensitivity in Multinuclear FlowNMR Spectroscopy. Chemistry 2023; 29:e202300215. [PMID: 36946535 PMCID: PMC10962566 DOI: 10.1002/chem.202300215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Revised: 03/22/2023] [Accepted: 03/22/2023] [Indexed: 03/23/2023]
Abstract
Sensitivity in FlowNMR spectroscopy for reaction monitoring often suffers from low levels of pre-magnetisation due to limited residence times of the sample in the magnetic field. While this in-flow effect is tolerable for high sensitivity nuclei such as 1 H and 19 F, it significantly reduces the signal-to-noise ratio in 31 P and 13 C spectra, making FlowNMR impractical for low sensititvity nuclei at low concentrations. Paramagnetic relaxation agents (PRAs), which enhance polarisation and spin-lattice relaxation, could eliminate the adverse in-flow effect and improve the signal-to-noise ratio. Herein, [Co(acac)3 ], [Mn(acac)3 ], [Fe(acac)3 ], [Cr(acac)3 ], [Ni(acac)2 ]3, [Gd(tmhd)3 ] and [Cr(tmhd)3 ] are investigated for their effectiveness in improving signal intensity per unit time in FlowNMR applications under the additional constraint of chemical inertness towards catalytically active transition metal complexes. High-spin Cr(III) acetylacetonates emerged as the most effective compounds, successfully reducing 31 P T1 values four- to five-fold at PRA concentrations as low as 10 mM without causing adverse line broadening. Whereas [Cr(acac)3 ] showed signs of chemical reactivity with a mixture of triphenylphosphine, triphenylphosphine oxide and triphenylphosphate over the course of several hours at 80° C, the bulkier [Cr(tmhd)3 ] was stable and equally effective as a PRA under these conditions. Compatibility with a range of representative transition metal complexes often used in homogeneous catalysis has been investigated, and application of [Cr(tmhd)3 ] in significantly improving 1 H and 31 P{1 H} FlowNMR data quality in a Rh-catalysed hydroformylation reaction has been demonstrated. With the PRA added, 13 C relaxation times were reduced more than six-fold, allowing quantitative reaction monitoring of substrate consumption and product formation by 13 C{1 H} FlowNMR spectroscopy at natural abundance.
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Affiliation(s)
- Alejandro Bara‐Estaún
- Department of ChemistryUniversity of Bath Claverton DownBathBA2 7AYUnited Kingdom
- Dynamic Reaction Monitoring FacilityUniversity of Bath, Claverton DownBathBA2 7AYUnited Kingdom
| | - Marie C. Harder
- Department of ChemistryUniversity of Bath Claverton DownBathBA2 7AYUnited Kingdom
- Dynamic Reaction Monitoring FacilityUniversity of Bath, Claverton DownBathBA2 7AYUnited Kingdom
| | - Catherine L. Lyall
- Department of ChemistryUniversity of Bath Claverton DownBathBA2 7AYUnited Kingdom
- Dynamic Reaction Monitoring FacilityUniversity of Bath, Claverton DownBathBA2 7AYUnited Kingdom
| | - John P. Lowe
- Department of ChemistryUniversity of Bath Claverton DownBathBA2 7AYUnited Kingdom
- Dynamic Reaction Monitoring FacilityUniversity of Bath, Claverton DownBathBA2 7AYUnited Kingdom
| | - Elizaveta Suturina
- Department of ChemistryUniversity of Bath Claverton DownBathBA2 7AYUnited Kingdom
| | - Ulrich Hintermair
- Department of ChemistryUniversity of Bath Claverton DownBathBA2 7AYUnited Kingdom
- Dynamic Reaction Monitoring FacilityUniversity of Bath, Claverton DownBathBA2 7AYUnited Kingdom
- Institute for SustainabilityUniversity of BathBathBA2 7AYUnited Kingdom
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Wakabayashi S, Takumi M, Kamio S, Wakioka M, Ohki Y, Nagaki A. Flow-Chemistry-Enabled Synthesis of 5-Diethylboryl-2,3'-bipyridine and Its Self-Assembly Dynamics. Chemistry 2023; 29:e202202882. [PMID: 36394125 DOI: 10.1002/chem.202202882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 11/03/2022] [Accepted: 11/14/2022] [Indexed: 11/19/2022]
Abstract
5-Diethylboryl-2,3'-bipyridine (1), which is inaccessible by conventional batch methods, was synthesized by using a flow microreactor. Compound 1 was obtained as an equilibrium mixture of a cyclic trimer and a cyclic tetramer in solution, the latter of which was crystallized in benzene by vapor diffusion of hexane at 7 °C. The dynamic nature of this system was confirmed by solvent- and concentration-dependent experiments. Notably, the dynamics was verified by using flow NMR spectroscopy, which revealed that the time required to reach equilibrium was influenced by the solvent ratio (<18 s, 24-28 s, and 34-42 s in 2 : 1, 1 : 1, and 1 : 2 mixtures of [D6 ]acetone and C6 D6 , respectively). Compound 1 and 3-[4'-(diethylboryl)phenyl]pyridine (2) exhibited different self-assembly behavior in solution and crystals. Density functional theory calculations suggested that this difference was largely due to enhanced planarity between two consecutive aromatic rings.
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Affiliation(s)
- Shigeharu Wakabayashi
- Department of Clinical Nutrition, Faculty of Health Science, Suzuka University of Medical Science, Suzuka, Mie, 510-0293, Japan
| | - Masahiro Takumi
- Department of Synthetic and Biological Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan
| | - Shintaro Kamio
- Department of Chemistry, Graduate School of Science, Hokkaido University, Sapporo, 060-0810, Japan
| | - Masayuki Wakioka
- Institute for Chemical Research, Kyoto University, Uji, Kyoto, 611-0011, Japan
| | - Yasuhiro Ohki
- Institute for Chemical Research, Kyoto University, Uji, Kyoto, 611-0011, Japan
| | - Aiichiro Nagaki
- Department of Chemistry, Graduate School of Science, Hokkaido University, Sapporo, 060-0810, Japan
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7
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Bazzoni M, Lhoste C, Bonnet J, Konan KE, Bernard A, Giraudeau P, Felpin FX, Dumez JN. In-line Multidimensional NMR Monitoring of Photochemical Flow Reactions. Chemistry 2023; 29:e202203240. [PMID: 36651473 DOI: 10.1002/chem.202203240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 01/13/2023] [Accepted: 01/16/2023] [Indexed: 01/19/2023]
Abstract
This work demonstrates the in-line monitoring of a flow photochemical reaction using 1D and ultrafast 2D NMR methods at high magnetic field. The reaction mixture exiting the flow reactor is flown through the NMR spectrometer and directly analyzed. In the case of simple substrates, suitable information can be obtained through 1D 1 H spectra, but for molecules of higher complexity the use of 2D experiments is key to address signal overlaps and assignment issues. Here we show the usefulness of ultrafast 2D COSY experiments acquired in 70 s or less, for the in-line monitoring of photochemical reactions, and the possibility to obtain reliable quantitative information. This is a powerful framework to, for example, efficiently screen reaction conditions.
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Affiliation(s)
| | - Célia Lhoste
- Nantes Université, CNRS, CEISAM UMR6230, F-4400, Nantes, France
| | - Justine Bonnet
- Nantes Université, CNRS, CEISAM UMR6230, F-4400, Nantes, France
| | | | - Aurélie Bernard
- Nantes Université, CNRS, CEISAM UMR6230, F-4400, Nantes, France
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8
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Mishra R, Dumez JN. Theoretical analysis of flow effects in spatially encoded diffusion NMR. J Chem Phys 2023; 158:014204. [PMID: 36610961 DOI: 10.1063/5.0130125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The measurement of translational diffusion coefficients by nuclear magnetic resonance (NMR) spectroscopy is essential in a broad range of fields, including organic, inorganic, polymer, and supramolecular chemistry. It is also a powerful method for mixture analysis. Spatially encoded diffusion NMR (SPEN DNMR)" is a time efficient technique to collect diffusion NMR data, which is particularly relevant for the analysis of samples that evolve in time. In many cases, motion other than diffusion is present in NMR samples. This is, for example, the case of flow NMR experiments, such as in online reaction monitoring and in the presence of sample convection. Such motion is deleterious for the accuracy of DNMR experiments in general and for SPEN DNMR in particular. Limited theoretical understanding of flow effects in SPEN DNMR experiments is an obstacle for their broader experimental implementation. Here, we present a detailed theoretical analysis of flow effects in SPEN DNMR and of their compensation, throughout the relevant pulse sequences. This analysis is validated by comparison with numerical simulation performed with the Fokker-Planck formalism. We then consider, through numerical simulation, the specific cases of constant, laminar, and convection flow and the accuracy of SPEN DNMR experiments in these contexts. This analysis will be useful for the design and implementation of fast diffusion NMR experiments and for their applications.
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Affiliation(s)
- Rituraj Mishra
- CNRS, CEISAM, Nantes Université, UMR 6230, F-4400 Nantes, France
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9
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Tadiello L, Drexler HJ, Beweries T. Low-Field Flow 31P NMR Spectroscopy for Organometallic Chemistry: On-Line Analysis of Highly Air-Sensitive Rhodium Diphosphine Complexes. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Laura Tadiello
- Leibniz Institut für Katalyse e.V., Albert-Einstein-Strasse 29a, 18059 Rostock, Germany
| | - Hans-Joachim Drexler
- Leibniz Institut für Katalyse e.V., Albert-Einstein-Strasse 29a, 18059 Rostock, Germany
| | - Torsten Beweries
- Leibniz Institut für Katalyse e.V., Albert-Einstein-Strasse 29a, 18059 Rostock, Germany
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10
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Marchand A, Mishra R, Bernard A, Dumez J. Online Reaction Monitoring with Fast and Flow‐Compatible Diffusion NMR Spectroscopy. Chemistry 2022; 28:e202201175. [DOI: 10.1002/chem.202201175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Indexed: 11/08/2022]
Affiliation(s)
| | - Rituraj Mishra
- Nantes Université CNRS CEISAM UMR 6230 44000 Nantes France
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11
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Bara-Estaun A, Lyall C, Lowe JP, Pringle PG, Kamer P, Franke R, Hintermair U. Mapping Catalyst Activation, Turnover Speciation and Deactivation in Rh/PPh3-catalysed Olefin Hydroformylation. Catal Sci Technol 2022. [DOI: 10.1039/d2cy00312k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report new insights into the fate of the precious metal during hydroformylation catalysis of 1-hexene with Rh/PPh3 complexes using multi-nuclear operando FlowNMR spectroscopy. By applying selectively excited 1H and...
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12
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Thomlinson IA, Davidson M, Lyall C, Lowe JP, Hintermair U. Fast and Accurate Diffusion NMR Acquisition in Continuous Flow. Chem Commun (Camb) 2022; 58:8242-8245. [DOI: 10.1039/d2cc03054c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
FlowNMR spectroscopy has become a popular and powerful technique for online reaction monitoring. DOSY NMR is an established technique for obtaining information about diffusion rates and molecular size on static...
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Berry DBG, Clegg I, Codina A, Lyall CL, Lowe JP, Hintermair U. Convenient and accurate insight into solution-phase equilibria from FlowNMR titrations. REACT CHEM ENG 2022. [DOI: 10.1039/d2re00123c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Solution phase titrations are made easy by multi-nuclear FlowNMR spectroscopy with automated, continuous titre addition to give accurate insights into Brønsted acid/base, hydrogen bonding, Lewis acid/base and metal/ligand binding equilibria under native conditions.
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Affiliation(s)
- Daniel B. G. Berry
- Department of Chemistry, University of Bath, Claverton Down, BA2 7AY Bath, UK
- Dynamic Reaction Monitoring Facility, University of Bath, Claverton Down, BA2 7AY Bath, UK
| | - Ian Clegg
- Bruker UK Ltd, Banner Lane, CV4 9GH Coventry, UK
| | - Anna Codina
- Bruker UK Ltd, Banner Lane, CV4 9GH Coventry, UK
| | - Catherine L. Lyall
- Department of Chemistry, University of Bath, Claverton Down, BA2 7AY Bath, UK
- Dynamic Reaction Monitoring Facility, University of Bath, Claverton Down, BA2 7AY Bath, UK
| | - John P. Lowe
- Department of Chemistry, University of Bath, Claverton Down, BA2 7AY Bath, UK
- Dynamic Reaction Monitoring Facility, University of Bath, Claverton Down, BA2 7AY Bath, UK
| | - Ulrich Hintermair
- Department of Chemistry, University of Bath, Claverton Down, BA2 7AY Bath, UK
- Dynamic Reaction Monitoring Facility, University of Bath, Claverton Down, BA2 7AY Bath, UK
- Centre for Sustainable and Circular Technologies, University of Bath, Claverton Down, BA2 7AY Bath, UK
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