Kinetic and thermodynamic characterization of C-N bond rotation by N-methylacetohydroxamic acid in aqueous media
Copyright © 2015 John Wiley & Sons, Ltd.
Veröffentlicht in: | Magnetic resonance in chemistry : MRC. - 1985. - 54(2016), 1 vom: 19. Jan., Seite 46-50 |
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1. Verfasser: | |
Weitere Verfasser: | , , , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2016
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Zugriff auf das übergeordnete Werk: | Magnetic resonance in chemistry : MRC |
Schlagworte: | Journal Article 1H Arrhenius analysis EXSY NMR hydroxamic acids rotational barrier variable temperature |
Zusammenfassung: | Copyright © 2015 John Wiley & Sons, Ltd. Hydroxamic acids (HAs) perform tasks in medicine and industry that require bidentate metal binding. The two favored conformations of HAs are related by rotation around the C(=O)-N bond. The conformations are unequal in stability. Recently, we reported that the most stable conformation of a small secondary HA in water places the oxygen atoms anti to one another. The barrier to C-N bond rotation may therefore modulate metal binding by secondary HAs in aqueous media. We have now determined the activation barrier to C-N rotation from major to minor conformation of a small secondary HA in D2O to be 67.3 kJ/mol. The HA rotational barrier scales with solvent polarity, as is observed in amides, although the HA barrier is less than that of a comparable tertiary amide in aqueous solution. Successful design of new secondary HAs to perform specific tasks requires solid understanding of rules governing HA structural behavior. Results from this work provide a more complete foundation for HA design efforts |
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Beschreibung: | Date Completed 08.04.2016 Date Revised 18.12.2015 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
ISSN: | 1097-458X |
DOI: | 10.1002/mrc.4318 |