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Communication
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Bringing our results together with the lack of previous direct
spectroscopic observations of NHCs in ionic liquids suggests
that NHCs are spontaneously formed in ionic liquids in low
concentrations and/or are very short-lived, transient species.
However, for NHCs then to be responsible for the initiation of a
range of reactions implies that they are highly reactive and that
they are rapidly replaced when they do react. Finally, it should
be noted that it is possible that the presence of neutral species,
whether reactants or not, in the ionic liquid increases the
extent of the formation of the NHC and it does remain a
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liquids and that these are the catalytically active species.
We are continuing to investigate these processes.
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We would like to thank the Universiti Malaysia Perlis and
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scholarship (NMAND).
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Conflicts of interest
There are no conflicts to declare.
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1156 | Chem. Commun., 2017, 53, 11154--11156
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