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Cyclic nitrones: oxidation studies and the synthesis of a heterocyclic nitrone

Part I: The synthesis of the heterocyclic nitrone, Δ³-dihydro-1,4-oxazine 4-oxide, by the oxidation of solutions of 4-hydroxymorpholine is described. The UV and IR spectra of the solutions were consistent with the structure proposed. Removal of the solvent gave linear polymers with the N-O-C repeati...

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Main Author: Elsworth, John Francis
Other Authors: Lamchen, M
Format: Thesis
Language:English
Published: Department of Chemistry 2017
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access_status_str Open Access
author Elsworth, John Francis
author2 Lamchen, M
author_browse Elsworth, John Francis
Lamchen, M
author_facet Lamchen, M
Elsworth, John Francis
author_sort Elsworth, John Francis
collection Thesis
description Part I: The synthesis of the heterocyclic nitrone, Δ³-dihydro-1,4-oxazine 4-oxide, by the oxidation of solutions of 4-hydroxymorpholine is described. The UV and IR spectra of the solutions were consistent with the structure proposed. Removal of the solvent gave linear polymers with the N-O-C repeating unit. Typical nitrone-reducing agents have been shown to be effective towards the heterocyclic nitrone. Arylhydrazines oxidised the heterocyclic nitrone with cleavage of the ether band, yielding glyoxal osazones. The same nitrone was very rapidly oxidised to 4-hydroxy-3-morpholone by ferric chloride. This cyclic hydroxamic acid underwent further oxidation at a slower rate, ultimately yielding diglycollic acid and nitrous oxide. 1,3-Cycloaddition products were formed when the heterocyclic nitrone was heated together with cyclohexene, with phenylisocyanate and with ethyl acrylate. All the products incorporated the fused bicyclic skeleton of morpholino-isoxazolidine and were each characterised by analysis, IR and p.m.r. spectra. Part 2: Cyclic aldonitrones and some related cyclic hydroxylamines have been shown to undergo oxidation by ferric chloride to cyclic hydroxamic acids. For example, the 2-unsubstituted 1-pyrroline 1-oxides gave l-hydroxy-2-pyrrolidones , and 1-piperideine 1-oxide gave 1-hydroxy-2-piperidone. The reaction could be followed titrimetrically or spectrophotometrically. The former involved the determination of the ferrous ion released, whereas the latter technique entailed observing the increase in the intensity of the colour of the solution.
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language eng
last_indexed 2026-06-10T12:33:40.116Z
license_str Not specified — see source repository
provenance_str_mv Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository
publishDate 2017
publishDateRange 2017
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publisher Department of Chemistry
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spelling oai:open.uct.ac.za:11427/23211 Cyclic nitrones: oxidation studies and the synthesis of a heterocyclic nitrone Elsworth, John Francis Lamchen, M Chemistry Part I: The synthesis of the heterocyclic nitrone, Δ³-dihydro-1,4-oxazine 4-oxide, by the oxidation of solutions of 4-hydroxymorpholine is described. The UV and IR spectra of the solutions were consistent with the structure proposed. Removal of the solvent gave linear polymers with the N-O-C repeating unit. Typical nitrone-reducing agents have been shown to be effective towards the heterocyclic nitrone. Arylhydrazines oxidised the heterocyclic nitrone with cleavage of the ether band, yielding glyoxal osazones. The same nitrone was very rapidly oxidised to 4-hydroxy-3-morpholone by ferric chloride. This cyclic hydroxamic acid underwent further oxidation at a slower rate, ultimately yielding diglycollic acid and nitrous oxide. 1,3-Cycloaddition products were formed when the heterocyclic nitrone was heated together with cyclohexene, with phenylisocyanate and with ethyl acrylate. All the products incorporated the fused bicyclic skeleton of morpholino-isoxazolidine and were each characterised by analysis, IR and p.m.r. spectra. Part 2: Cyclic aldonitrones and some related cyclic hydroxylamines have been shown to undergo oxidation by ferric chloride to cyclic hydroxamic acids. For example, the 2-unsubstituted 1-pyrroline 1-oxides gave l-hydroxy-2-pyrrolidones , and 1-piperideine 1-oxide gave 1-hydroxy-2-piperidone. The reaction could be followed titrimetrically or spectrophotometrically. The former involved the determination of the ferrous ion released, whereas the latter technique entailed observing the increase in the intensity of the colour of the solution. 2017-01-26T07:16:21Z 2017-01-26T07:16:21Z 1967 2016-11-22T09:29:11Z Thesis http://hdl.handle.net/11427/23211 eng application/pdf Department of Chemistry Faculty of Science University of Cape Town
spellingShingle Chemistry
Elsworth, John Francis
Cyclic nitrones: oxidation studies and the synthesis of a heterocyclic nitrone
title Cyclic nitrones: oxidation studies and the synthesis of a heterocyclic nitrone
title_full Cyclic nitrones: oxidation studies and the synthesis of a heterocyclic nitrone
title_fullStr Cyclic nitrones: oxidation studies and the synthesis of a heterocyclic nitrone
title_full_unstemmed Cyclic nitrones: oxidation studies and the synthesis of a heterocyclic nitrone
title_short Cyclic nitrones: oxidation studies and the synthesis of a heterocyclic nitrone
title_sort cyclic nitrones oxidation studies and the synthesis of a heterocyclic nitrone
topic Chemistry
url http://hdl.handle.net/11427/23211
work_keys_str_mv AT elsworthjohnfrancis cyclicnitronesoxidationstudiesandthesynthesisofaheterocyclicnitrone