Detailed mechanistic studies on palladium catalyzed selective C-H olefination with aliphatic alkenes: a significant influence of proton shuttling
Directing group assisted regioselective C-H olefination with electronically biased olefins are well studied. However, the incorporation of unactivated olefins has remained largely unsuccessful. A proper mechanistic understanding of olefination involving unactivated alkenes is therefore essential for...
| Main Authors: | , , , , |
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| Format: | Journal article |
| Language: | English |
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ACS Publications
2016
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| _version_ | 1797058667503157248 |
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| author | Deb, A Hazra, A Peng, Q Paton, R Maiti, D |
| author_facet | Deb, A Hazra, A Peng, Q Paton, R Maiti, D |
| author_sort | Deb, A |
| collection | OXFORD |
| description | Directing group assisted regioselective C-H olefination with electronically biased olefins are well studied. However, the incorporation of unactivated olefins has remained largely unsuccessful. A proper mechanistic understanding of olefination involving unactivated alkenes is therefore essential for enhancing their usage in future. In this article, detailed experimental and computational mechanistic studies on palladium catalyzed C-H olefination with unactivated, aliphatic alkenes are described. The isolation of a Pd(II) intermediates are shown to be effective for elucidating the elementary steps involved in catalytic olefination. Reaction rate and order determination, control experiments, isotopic labeling studies and Hammett analysis have been used to understand the reaction mechanism. The results from these experimental studies implicate β-hydride elimination as the rate-determining step and that a mechanistic switch occurs between cationic and neutral pathway. Computational studies support this interpretation of the experimental evidence and are used to uncover the role of proton on the origins of selectivity. |
| first_indexed | 2024-03-06T19:53:31Z |
| format | Journal article |
| id | oxford-uuid:24c6c573-6b8d-448a-8847-bf1eafb2411c |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T19:53:31Z |
| publishDate | 2016 |
| publisher | ACS Publications |
| record_format | dspace |
| spelling | oxford-uuid:24c6c573-6b8d-448a-8847-bf1eafb2411c2022-03-26T11:51:54ZDetailed mechanistic studies on palladium catalyzed selective C-H olefination with aliphatic alkenes: a significant influence of proton shuttlingJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:24c6c573-6b8d-448a-8847-bf1eafb2411cEnglishSymplectic Elements at OxfordACS Publications2016Deb, AHazra, APeng, QPaton, RMaiti, DDirecting group assisted regioselective C-H olefination with electronically biased olefins are well studied. However, the incorporation of unactivated olefins has remained largely unsuccessful. A proper mechanistic understanding of olefination involving unactivated alkenes is therefore essential for enhancing their usage in future. In this article, detailed experimental and computational mechanistic studies on palladium catalyzed C-H olefination with unactivated, aliphatic alkenes are described. The isolation of a Pd(II) intermediates are shown to be effective for elucidating the elementary steps involved in catalytic olefination. Reaction rate and order determination, control experiments, isotopic labeling studies and Hammett analysis have been used to understand the reaction mechanism. The results from these experimental studies implicate β-hydride elimination as the rate-determining step and that a mechanistic switch occurs between cationic and neutral pathway. Computational studies support this interpretation of the experimental evidence and are used to uncover the role of proton on the origins of selectivity. |
| spellingShingle | Deb, A Hazra, A Peng, Q Paton, R Maiti, D Detailed mechanistic studies on palladium catalyzed selective C-H olefination with aliphatic alkenes: a significant influence of proton shuttling |
| title | Detailed mechanistic studies on palladium catalyzed selective C-H olefination with aliphatic alkenes: a significant influence of proton shuttling |
| title_full | Detailed mechanistic studies on palladium catalyzed selective C-H olefination with aliphatic alkenes: a significant influence of proton shuttling |
| title_fullStr | Detailed mechanistic studies on palladium catalyzed selective C-H olefination with aliphatic alkenes: a significant influence of proton shuttling |
| title_full_unstemmed | Detailed mechanistic studies on palladium catalyzed selective C-H olefination with aliphatic alkenes: a significant influence of proton shuttling |
| title_short | Detailed mechanistic studies on palladium catalyzed selective C-H olefination with aliphatic alkenes: a significant influence of proton shuttling |
| title_sort | detailed mechanistic studies on palladium catalyzed selective c h olefination with aliphatic alkenes a significant influence of proton shuttling |
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