Linked Life Data

11724598

Source:http://linkedlifedata.com/resource/pubmed/id/11724598

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
48
pubmed:dateCreated
2001-11-28
pubmed:abstractText
The mechanism of the selective conversion of 1-alkynes to aldehydes by hydration was investigated by isolating organic and organometallic byproducts, deuterium-labeling experiments, and DFT calculations. The D-labeled acetylenic hydrogen of 1-alkyne was found exclusively in the formyl group of the resulting aldehydes. After the reaction, the presence of metal-coordinated CO was confirmed. All of the experimental results strongly suggest the involvement of a metal-acyl intermediate with the original acetylenic hydrogen also bound to the metal center as a hydride, with the next step being release of aldehyde by reductive elimination. Theoretical analyses suggest that the first step of the catalytic cycle is not oxidative addition of acetylene C [bond] H or tautomerization of eta(2)-alkyne to a vinylidene complex, but rather protonation of the coordinated 1-alkyne at the substituted carbon to form a metal-vinyl intermediate. This cationic intermediate then isomerizes to Ru(IV)-hydride-vinylidene via alpha-hydride migration of the vinyl group to the metal center, followed by attack of the vinylidene alpha-carbon by OH(-) to give the metal-hydride-acyl intermediate.
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Dec
pubmed:issn
0002-7863
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
123
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11917-24
pubmed:dateRevised
2003-10-31
pubmed:year
2001
pubmed:articleTitle
Ruthenium-catalyzed hydration of 1-alkynes to give aldehydes: insight into anti-Markovnikov regiochemistry.
pubmed:affiliation
RIKEN, The Institute of Physical and Chemical Research, Wako-shi, Saitama 351-0198, Japan.
pubmed:publicationType
Journal Article