300 MHz NMR spectrometer console

• Subject Area: Molecular Chemistry
• Term: Funded in 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 443450867

NMR spectroscopy is the most important method for the analysis of molecular structures that are synthesized in the working groups of organic and inorganic chemistry in our department. The analytical questions range from the spin systems of complex CH frameworks over NMR-active hetero-nuclei to the characterization of intermolecular interactions and relaxation properties. The synthesis of polypeptides, natural products and catalysts in organic chemistry requires the structure elucidation of numerous intermediates, for which a reliable NMR analysis is a requirement. Since there are no reference spectra for these new molecular structures, the structural evidence must generally be carried out using two-dimensional NMR methods. Just as many structural questions come from inorganic chemistry, with the focus more on the determination of heteroatoms such as fluorine and phosphorus, but also elements with nuclear spin > ½. The highly experimental education brings students in contact with the NMR spectrometers at an early stage. The pyramidal structure of our spectrometers has proven itself for the complexity of scientific questions: one 600, two 500 and four 300/250. With the failure of our oldest 300 MHz spectrometer console, a quarter of the measurement time previously available for the low-field spectrometers has been lost. This limitation has to be compensated for by purchasing a new console. The developments in computer technology in recent years have made modern NMR consoles versatile instruments that offer not only increased sensitivity, but also new NMR techniques, which can be used to clarify new scientific questions. The applicants have high expectations for the technology of "multi-receiver acquisition". Heteronuclear correlations can thus be measured much more efficiently, since correlations that are independent of one another, e.g. H,H- or C,F- are detected simultaneously and two NMR measurements are carried out simultaneously in one measurement time window. The associated considerable reduction in the total measuring time not only ensures more efficient use of the spectrometer, it also enables, for example, thecomplete NMR analysis of unstable reaction intermediates that would decompose with longer measuring times. All working groups represented in this application can benefit from these new NMR techniques.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: 300 MHz NMR Spektrometerkonsole
• Instrumentation Group: 1740 Hochauflösende NMR-Spektrometer
• Applicant Institution: Philipps-Universität Marburg
• Leader: Professor Dr. Armin Geyer