Low-Temperature NMR Characterization of Reaction of Sodium Pyruvate with Hydrogen Peroxide
View/ Open
Issue Date
2015-02-12Author
Asmus, Christopher Erik Helmut
Mozziconacci, Olivier
Schöneich, Christian
Publisher
American Chemical Society
Type
Article
Article Version
Scholarly/refereed, author accepted manuscript
Rights
This document is the Accepted Manuscript version of a Published Work that appeared in final form in the Journal of Physical Chemistry A, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://dx.doi.org/10.1021/jp511831b.
Metadata
Show full item recordAbstract
It was proposed that the reaction of sodium pyruvate and H2O2 generates the intermediate 2-hydroperoxy-2-hydroxypropanoate, which converts into acetate, CO2, and H2O (Aleksankin et al. Kernenergie 1962, 5, 362–365). These conclusions were based on the products generated in 18O-enriched water and H2O2 reacting with pyruvic acid at room temperature; however, the lifetime of 2-hydroperoxy-2-hydroxypropanoate at room temperature is too short for direct spectroscopic observation. Therefore, we applied the combination of low-temperature and 13C NMR techniques to verify, for the first time, the formation of 2-deuteroperoxy-2-deuteroxypropanoate in mixtures of D2O and methanol-d4 and to monitor directly each species involved in the reaction between D2O2 and 13C-enriched pyruvate. Our NMR results confirm the formation of 2-deuteroperoxy-2-deuteroxypropanoate, where the respective chemical shifts are supported by density functional theory (DFT) calculations. At near-neutral apparent pD (pD*) and −35 °C, the formation of 2-deuteroperoxy-2-deuteroxypropanoate occurred with k = 2.43 × 10−3 dm3·mol−1·s−1. The subsequent decomposition of 2-deuteroperoxy-2-deuteroxypropanoate into acetate, CO2, and D2O occurred with k = 2.58 × 10−4 s−1 at −35 °C. In order to provide a full kinetic analysis, we also monitored the equilibrium of pyruvate and methanol with the hemiacetal (2-deuteroxy-2-methoxypropanoate). The kinetics for the reaction of sodium pyruvate and D2O2 were fitted by taking into account all these equilibria and species.
Collections
Citation
Asmus, C., Mozziconacci, O., & Schöneich, C. (2015). Low-Temperature NMR Characterization of Reaction of Sodium Pyruvate with Hydrogen Peroxide. The Journal of Physical Chemistry. A, 119(6), 966–977. http://doi.org/10.1021/jp511831b
Items in KU ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.
We want to hear from you! Please share your stories about how Open Access to this item benefits YOU.