Clarification of the stereochemical course of nucleophilic substitution of arylsulfonate-based nucleophile assisting leaving groups.
Secondary alcohols modified as tosylates, PEG-sulfonates, or quisylates undergo inversion of configuration at the reacting center when treated with lithium halide in acetone at reflux, where the PEG-sulfonates and quisylates are substantially more reactive. In sterically hindered cases, elimination...
| Main Authors: | , , , |
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| Format: | Journal article |
| Language: | English |
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2009
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| _version_ | 1797060674586673152 |
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| author | Braddock, D Pouwer, R Burton, J Broadwith, P |
| author_facet | Braddock, D Pouwer, R Burton, J Broadwith, P |
| author_sort | Braddock, D |
| collection | OXFORD |
| description | Secondary alcohols modified as tosylates, PEG-sulfonates, or quisylates undergo inversion of configuration at the reacting center when treated with lithium halide in acetone at reflux, where the PEG-sulfonates and quisylates are substantially more reactive. In sterically hindered cases, elimination is a competing process. In contrast, when treated with TiCl(4), simple secondary sulfonates give chloride products with partial inversion of configuration. Any observed retention of configuration in a given alkyl sulfonate substrate under these conditions is likely due to neighboring group participation or diastereoselective attack on a carbocation (or ion pair) rather than an S(N)i mechanism. |
| first_indexed | 2024-03-06T20:20:27Z |
| format | Journal article |
| id | oxford-uuid:2d9f1400-f9e9-4ab2-ad8d-6b95cc244f54 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T20:20:27Z |
| publishDate | 2009 |
| record_format | dspace |
| spelling | oxford-uuid:2d9f1400-f9e9-4ab2-ad8d-6b95cc244f542022-03-26T12:44:00ZClarification of the stereochemical course of nucleophilic substitution of arylsulfonate-based nucleophile assisting leaving groups.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:2d9f1400-f9e9-4ab2-ad8d-6b95cc244f54EnglishSymplectic Elements at Oxford2009Braddock, DPouwer, RBurton, JBroadwith, PSecondary alcohols modified as tosylates, PEG-sulfonates, or quisylates undergo inversion of configuration at the reacting center when treated with lithium halide in acetone at reflux, where the PEG-sulfonates and quisylates are substantially more reactive. In sterically hindered cases, elimination is a competing process. In contrast, when treated with TiCl(4), simple secondary sulfonates give chloride products with partial inversion of configuration. Any observed retention of configuration in a given alkyl sulfonate substrate under these conditions is likely due to neighboring group participation or diastereoselective attack on a carbocation (or ion pair) rather than an S(N)i mechanism. |
| spellingShingle | Braddock, D Pouwer, R Burton, J Broadwith, P Clarification of the stereochemical course of nucleophilic substitution of arylsulfonate-based nucleophile assisting leaving groups. |
| title | Clarification of the stereochemical course of nucleophilic substitution of arylsulfonate-based nucleophile assisting leaving groups. |
| title_full | Clarification of the stereochemical course of nucleophilic substitution of arylsulfonate-based nucleophile assisting leaving groups. |
| title_fullStr | Clarification of the stereochemical course of nucleophilic substitution of arylsulfonate-based nucleophile assisting leaving groups. |
| title_full_unstemmed | Clarification of the stereochemical course of nucleophilic substitution of arylsulfonate-based nucleophile assisting leaving groups. |
| title_short | Clarification of the stereochemical course of nucleophilic substitution of arylsulfonate-based nucleophile assisting leaving groups. |
| title_sort | clarification of the stereochemical course of nucleophilic substitution of arylsulfonate based nucleophile assisting leaving groups |
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