Development of low-field flow 31P NMR spectroscopy for reaction monitoring in organometallic chemistry
Nuclear magnetic resonance
Tadiello, Laura
1996-
VerfasserIn
aut
Beweries, Torsten
1982-
AkademischeR BetreuerIn
dgs
Corzilius, Björn
1979-
AkademischeR BetreuerIn
dgs
Universität Rostock
Grad-verleihende Institution
dgg
Universität Rostock
Mathematisch-Naturwissenschaftliche Fakultät
Grad-verleihende Institution
dgg
text
theses
Text
Hochschulschrift
gw
2024
monographic
XA-DE
Rostock
Universität Rostock
publisher
2024
Rostock
Universitätsbibliothek Rostock
distributor
eng
application/pdf
1 Online-Ressource (xvi, 121 Seiten) Illustrationen, Diagramme
Benchtop low-field (LF) NMR spectroscopy is a valuable tool for reaction monitoring and its application in catalysis. It is particularly attractive thanks to its low-cost and portability (i.e., the instrument can be installed right next to the fume hood). However, crucial quantitative results, e.g., kinetic profiles, cannot be correctly determined the moment degradation of an air- and moisture-sensitive catalyst occurs. Therefore, inertness of the entire setup must be guaranteed. In the first part of this thesis, it is demonstrated that this challenge could be overcome to meet the experimental requirements of highly oxygen-sensitive rhodium diphosphine complexes, relevant for homogeneous catalysis. Indeed, a commercially available benchtop LF NMR spectrometer has been evolved into an inert customized flow setup. Catalytic hydrogenation monitoring via LF 1H and 31P NMR spectroscopy proved to be suitable with this flow setup despite the relatively low concentration of the investigated species (ca. 10 mM). In the second part of the thesis, limitations due to the low magnetic field of the benchtop spectrometer (1.9 T) and the relative insensitivity of 31P compared to 1H nucleus have been faced. 31P NMR signal-to-noise ratios (SNRs) have been improved using advanced pulse sequences. Sensitive Homogeneous And Resolved PEaks in Real time (SHARPER) enhances 31P NMR signals by collapsing the target resonance into an extremely narrow singlet and eliminating the effects of field inhomogeneity. After demonstrating the advantage of this tool in static conditions (up to 10-fold enhancement factor on SNR), the customized on-line setup has been used to monitor a faster reaction (in the order of minutes), that could not be followed with traditional 31P NMR sequences.<eng>
Open Access
Urheberrechtsschutz 1.0
vorgelegt von Laura Tadiello
GutachterInnen: Torsten Beweries (Leibniz-Institut für Katalyse e. V.) ; Björn Corzilius (Universität Rostock, Institut für Chemie)
Dissertation Universität Rostock 2024
540
543
540
https://purl.uni-rostock.de/rosdok/id00004876
https://doi.org/10.18453/rosdok_id00004876
https://nbn-resolving.org/urn:nbn:de:gbv:28-rosdok_id00004876-1
https://d-nb.info/1373150661/34
Development of low-field flow 31P NMR spectroscopy for reaction monitoring in organometallic chemistry
Rostock : Universität Rostock, 2024
Druck-Ausgabe
(DE-627)1931404364
Tadiello, Laura, 1996 -
urn:nbn:de:gbv:28-rosdok_id00004876-1
10.18453/rosdok_id00004876
1528456914
rda
DE-627
250721
1931401799
20251227T185828.0
Converted from MARCXML to MODS version 3.8 using MARC21slim2MODS3-8_XSLT1-0.xsl
(Revision 1.174 20250328)
ger