The divergent effects of strong NHC donation in catalysis.
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ABSTRACT:
SUBMITTER: Lummiss JAM
PROVIDER: S-EPMC5947514 | biostudies-literature | 2015 Dec
REPOSITORIES: biostudies-literature
Publications
The divergent effects of strong NHC donation in catalysis.
Lummiss Justin A M JAM Higman Carolyn S CS Fyson Devon L DL McDonald Robert R Fogg Deryn E DE
Chemical science 20151006 12
Strong σ-donation from NHC ligands (NHC = N-heterocyclic carbene) is shown to have profoundly conflicting consequences for the reactivity of transition-metal catalysts. Such donation is regarded as central to high catalyst activity in many contexts, of which the second-generation Grubbs metathesis catalysts (RuCl<sub>2</sub>(NHC)(PCy<sub>3</sub>)([double bond, length as m-dash]CHPh), <b>GII</b>) offer an early, prominent example. Less widely recognized is the dramatically inhibiting impact of NH ...[more]
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