Source:http://linkedlifedata.com/resource/pubmed/id/21258300
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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
1
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pubmed:dateCreated |
2011-1-24
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pubmed:abstractText |
The atom-efficiency of one of the most widely used catalytic reactions for forging C-C bonds, the Tsuji-Trost reaction, is limited by the need of preoxidized reagents. This limitation can be overcome by utilization of the recently discovered palladium-catalyzed C-H activation, the allylic C-H alkylation reaction which is the topic of the current review. Particular emphasis is put on current mechanistic proposals for the three reaction types comprising the overall transformation: C-H activation, nucleophilic addition, and re-oxidation of the active catalyst. Recent advances in C-H bond activation are highlighted with emphasis on those leading to C-C bond formation, but where it was deemed necessary for the general understanding of the process closely related C-H oxidations and aminations are also included. It is found that C-H cleavage is most likely achieved by ligand participation which could involve an acetate ion coordinated to Pd. Several of the reported systems rely on benzoquinone for re-oxidation of the active catalyst. The scope for nucleophilic addition in allylic C-H alkylation is currently limited, due to demands on pK(a) of the nucleophile. This limitation could be due to the pH dependence of the benzoquinone/hydroquinone redox couple. Alternative methods for re-oxidation that does not rely on benzoquinone could be able to alleviate this limitation.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:issn |
1420-3049
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pubmed:author | |
pubmed:issnType |
Electronic
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pubmed:volume |
16
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
951-69
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pubmed:meshHeading | |
pubmed:year |
2011
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pubmed:articleTitle |
Palladium catalyzed allylic C-H alkylation: a mechanistic perspective.
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pubmed:affiliation |
Department of Chemistry, Technical University of Denmark, Kemitorvet Building 201, DK-2800, Kgs. Lyngby, Denmark.
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pubmed:publicationType |
Journal Article,
Review,
Research Support, Non-U.S. Gov't
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