Developments in chiral counterion-directed asymmetric reactions
<p>The research outlined herein consists of two projects, each relating to the investigation and development of asymmetric phase-transfer catalysed reactions.</p> <p>The aim of the first project was to develop a two-component cascade reaction that would assemble the valuable pyrrol...
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| Format: | Thesis |
| Language: | English |
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2016
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| _version_ | 1797112813331677184 |
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| author | Cavell, A |
| author2 | Smith, M |
| author_facet | Smith, M Cavell, A |
| author_sort | Cavell, A |
| collection | OXFORD |
| description | <p>The research outlined herein consists of two projects, each relating to the investigation and development of asymmetric phase-transfer catalysed reactions.</p> <p>The aim of the first project was to develop a two-component cascade reaction that would assemble the valuable pyrroloindoline framework from simple and readily available starting materials, namely an isocyanide-containing substrate and a Michael acceptor. Successfully, we were able to synthesise a variety of pyrroloindolines containing up to three stereocentres with excellent diastereo- and enantioselectivity.</p> <p>This rapid strategy uses a chiral ammonium salt to control the selectivity and exploits the remarkable reactivity profile of acidic isocyanides. A mechanistic proposal involving hydrogen-bond activation of the isocyanide is described, originating from the specific design of the Michael acceptor component.</p> <p>Meanwhile, the objective of the second project was to develop a desymmetrising S<sub>N</sub>2 reaction on achiral biaryl substrates under asymmetric phase-transfer conditions, offering a new pathway to axially chiral biaryls. We were able to generate such products, which can be subsequently derivatised, with tremendous enantioselectivity and pleasing diastereoselectivity, particularly when using a glycine Schiff base as the nucleophile.</p> |
| first_indexed | 2024-03-07T08:29:10Z |
| format | Thesis |
| id | oxford-uuid:70094e28-5c28-47b2-b828-30315a6e0c42 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T08:29:10Z |
| publishDate | 2016 |
| record_format | dspace |
| spelling | oxford-uuid:70094e28-5c28-47b2-b828-30315a6e0c422024-03-06T09:24:14ZDevelopments in chiral counterion-directed asymmetric reactionsThesishttp://purl.org/coar/resource_type/c_db06uuid:70094e28-5c28-47b2-b828-30315a6e0c42Asymmetric synthesisIsocyanidesHeterocyclic compoundsPhase-transfer catalysisEnglishORA Deposit2016Cavell, ASmith, M<p>The research outlined herein consists of two projects, each relating to the investigation and development of asymmetric phase-transfer catalysed reactions.</p> <p>The aim of the first project was to develop a two-component cascade reaction that would assemble the valuable pyrroloindoline framework from simple and readily available starting materials, namely an isocyanide-containing substrate and a Michael acceptor. Successfully, we were able to synthesise a variety of pyrroloindolines containing up to three stereocentres with excellent diastereo- and enantioselectivity.</p> <p>This rapid strategy uses a chiral ammonium salt to control the selectivity and exploits the remarkable reactivity profile of acidic isocyanides. A mechanistic proposal involving hydrogen-bond activation of the isocyanide is described, originating from the specific design of the Michael acceptor component.</p> <p>Meanwhile, the objective of the second project was to develop a desymmetrising S<sub>N</sub>2 reaction on achiral biaryl substrates under asymmetric phase-transfer conditions, offering a new pathway to axially chiral biaryls. We were able to generate such products, which can be subsequently derivatised, with tremendous enantioselectivity and pleasing diastereoselectivity, particularly when using a glycine Schiff base as the nucleophile.</p> |
| spellingShingle | Asymmetric synthesis Isocyanides Heterocyclic compounds Phase-transfer catalysis Cavell, A Developments in chiral counterion-directed asymmetric reactions |
| title | Developments in chiral counterion-directed asymmetric reactions |
| title_full | Developments in chiral counterion-directed asymmetric reactions |
| title_fullStr | Developments in chiral counterion-directed asymmetric reactions |
| title_full_unstemmed | Developments in chiral counterion-directed asymmetric reactions |
| title_short | Developments in chiral counterion-directed asymmetric reactions |
| title_sort | developments in chiral counterion directed asymmetric reactions |
| topic | Asymmetric synthesis Isocyanides Heterocyclic compounds Phase-transfer catalysis |
| work_keys_str_mv | AT cavella developmentsinchiralcounteriondirectedasymmetricreactions |