Electron spin resonance study of phosphorus-nitroxides from 1,3-additions of silicon-phosphorus reagents to nitrones
Copyright 2004 John Wiley & Sons, Ltd.
| Veröffentlicht in: | Magnetic resonance in chemistry : MRC. - 1985. - 42(2004), 10 vom: Okt., Seite 835-43 |
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| Weitere Verfasser: | , , |
| Format: | Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2004
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| Zugriff auf das übergeordnete Werk: | Magnetic resonance in chemistry : MRC |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Cyclic N-Oxides Hydroxylamines Nitrogen Oxides Organometallic Compounds Organosilicon Compounds Phosphorus Compounds nitrones Phosphorus mehr... |
| Zusammenfassung: | Copyright 2004 John Wiley & Sons, Ltd. This article explores a new, convenient route to beta-phosphorus nitroxides. Specifically, the reaction sequence involves the novel 1,3-addition of trimethylsilyl phosphites (e.g. diethyl) or trimethylsilyl phosphines (e.g. diphenyl) to aldo-nitrones [e.g. alpha-phenyl-N-tert-butylnitrone (PBN) or 5,5-dimethyl-l-pyrroline-N-oxide (DMPO)] or keto-nitrones [e.g. 2-ethyl-5,5-dimethyl-1 pyrroline-N-oxide (2-Et-DMPO) or 2-phenyl-5,5-dimethyl-l-pyrroline-N-oxide (2-Ph-DMPO)] to form alpha-phosphityl- or alpha-phosphinyl-O-silylhydroxylamines. Acidic hydrolysis provides the corresponding hydroxylamines that are easily oxidized to the title beta-phosphorus-nitroxides. ESR spectroscopic analysis revealed some very large beta-phosphorus hyperfine splittings (i.e. in excess of 5 mT). For this reason and their remarkable stability (persistence) some of these nitroxides show promise as integral components in new, improved weak-field dynamic nuclear polarization (DNP) magnetometers |
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| Beschreibung: | Date Completed 17.03.2005 Date Revised 24.11.2016 published: Print Citation Status MEDLINE |
| ISSN: | 0749-1581 |