.png){kind=icon}
.png){kind=icon}
Return
Rapid Decomposition of Olefin Metathesis Catalysts by a Truncated N-Heterocyclic Carbene: Efficient Catalyst Quenching and N-Heterocyclic Carbene Vinylation
.png){kind=icon}
PRE
AI
S
A
M
V
D
DOI：10.1021/acscatal.8b03123.png)
.png){kind=icon}
Original request for help.png){kind=icon}
Share.png){kind=icon}
Save
Abstract
En 中文
The Grubbs methylidene RuCl2(PCy3)(2)(=CH2) GIm is immediately decomposed by the small N-heterocyclic carbene (NHC) tetramethylimidazol-2-ylidene (IMe4), even at -80 degrees C. Labeling experiments with RuCl2(PCy3)(2)(=(CH2)-C-13) reveal capture of the methylidene ligand as ethylimidazolium chloride [(CH3CH2)-C-13-C-13-IMe4]Cl, A*. Density functional calculations indicate that IMe4 first abstracts methylidene from five-coordinate GIm (a pathway unavailable to bulkier NHCs), generating the N-heterocyclic olefin (NHO) H2C-IMe4. The latter attacks a second GIm; protonolysis of highly basic [Ru]-CH2CH2IMe4 then liberates A. Identical, slightly slower, reactivity is seen for RuCl2(H(2)IMes)(PCy3)(=CH2), GIIm. The high efficiency of this process opens up opportunities for tandem metathesis enabled by sterically accessible NHCs and NHOs.
Keywords:
homogeneous catalysis
olefin metathesis
N-heterocyclic carbene
N-heterocyclic olefin
nucleophilic attack
methylidene ligand
catalyst quenching
tandem catalysis
AI Summary
Key information extracted from the uploaded paper, including a brief overview, abstract, background, key highlights, visual analysis, and future outlook.
Journal
IF:
13.1
Papers:
1.6W
Citations:
15.0W
Organization
Cited Papers