TY - JOUR A1 - Zientek, Nicolai A1 - Laurain, C. A1 - Meyer, Klas A1 - Paul, Andrea A1 - Engel, D. A1 - Guthausen, G. A1 - Kraume, M. A1 - Maiwald, Michael T1 - Automated data evaluation and modelling of simultaneous F-19-H-1 medium-resolution NMR spectra for online reaction monitoring N2 - Medium-resolution nuclear magnetic resonance spectroscopy (MR-NMR) currently develops to an important analytical tool for both quality control and processmonitoring. In contrast to high-resolution onlineNMR (HR-NMR),MR-NMRcan be operated under rough environmental conditions. A continuous re-circulating stream of reaction mixture fromthe reaction vessel to the NMR spectrometer enables a non-invasive, volume integrating online analysis of reactants and products. Here, we investigate the esterification of 2,2,2-trifluoroethanol with acetic acid to 2,2,2-trifluoroethyl acetate both by 1H HR-NMR (500MHz) and 1H and 19F MRNMR (43MHz) as amodel system. The parallel online measurement is realised by splitting the flow,which allows the adjustment of quantitative and independent flow rates, both in the HR-NMR probe as well as in the MR-NMR probe, in addition to a fast bypass line back to the reactor. One of the fundamental acceptance criteria for online MR-MNR spectroscopy is a robust data treatment and evaluation strategy with the potential for automation. The MR-NMR spectra are treated by an automated baseline and phase correction using the minimum entropy method. The evaluation strategies comprise (i) direct integration, (ii) automated line fitting, (iii) indirect hard modelling (IHM) and (iv) partial least squares regression (PLS-R). To assess the potential of these evaluation strategies for MR-NMR, prediction results are compared with the line fitting data derived from the quantitative HR-NMR spectroscopy. Although, superior results are obtained from both IHM and PLS-R for 1H MR-NMR, especially the latter demands for elaborate data pretreatment, whereas IHM models needed no previous alignment. KW - NMR KW - 1H-NMR KW - 19F-NMR KW - Medium-resolution NMR KW - Online NMR KW - Quantitative NMR KW - Reaction monitoring KW - Data processing KW - Automation KW - Process analytical technology KW - IHM KW - Indirect hard modeling KW - Chemometrics KW - PLS-R KW - Partial least squares regression PY - 2016 UR - http://onlinelibrary.wiley.com/doi/10.1002/mrc.4216/abstract U6 - https://doi.org/doi:10.1002/mrc.4216 VL - 54 SP - 513 EP - 520 PB - John Wiley & Sons, Ltd CY - Hoboken, New Jersey, USA AN - OPUS4-36135 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -