Source:http://linkedlifedata.com/resource/pubmed/id/12950224
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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
18
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| pubmed:dateCreated |
2003-9-2
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| pubmed:abstractText |
An oxorhenium(V) dimer, [PMeReO(mtp)](2), D, where mtpH(2) is 2-(mercaptomethyl)thiophenol, catalyzes oxygen atom transfer reaction from methyl phenyl sulfoxide to triarylphosphines. Kinetic studies in benzene-d(6) at 23 degrees C indicate that the reaction takes place through the formation of an adduct between D and sulfoxide. The equilibrium constants, K(DL), for adduct formation were determined by spectrophotometric titration, and the values of K(DL) for MeS(O)C(6)H(4)-4-R were obtained as 14.1(2), 5.7(1), and 2.1(1) for R = Me, H, and Br, respectively. Following sulfoxide binding, oxygen atom transfer occurs with either internal or external nucleophilic assistance. Because [MeReO(mtp)](2) is a much more reactive catalyst than its monomerized form, MeReO(mtp)PPh(3), loss of the active catalyst during the time course of the reaction must be taken into account as a part of the kinetic analysis. As it happens, sulfoxide catalyzes monomerization. Monomerization by triarylphosphines was also studied in the presence of sulfoxide, and a mechanism for that reaction was also proposed. Both the phosphine-assisted monomerization and the phosphine-assisted pathway for oxygen atom transfer involve transition states with ternary components, D, sulfoxide, and phosphine, which we suggest are structural isomers of one another.
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| pubmed:language |
eng
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| pubmed:journal | |
| pubmed:status |
PubMed-not-MEDLINE
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| pubmed:month |
Sep
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| pubmed:issn |
0020-1669
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| pubmed:author | |
| pubmed:issnType |
Print
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| pubmed:day |
8
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| pubmed:volume |
42
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| pubmed:owner |
NLM
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| pubmed:authorsComplete |
Y
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| pubmed:pagination |
5735-42
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| pubmed:year |
2003
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| pubmed:articleTitle |
Kinetics and mechanism of oxygen atom transfer from methyl phenyl sulfoxide to triarylphosphines catalyzed by an oxorhenium(V) dimer.
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| pubmed:affiliation |
Ames Laboratory and Department of Chemistry, Iowa State University of Science and Technology, Ames, Iowa 50011, USA.
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| pubmed:publicationType |
Journal Article
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