Abstract
Intermolecular Pauson-Khand reactions of strained alkenes 1a-d with
alkynes 2, 4, 6 and Co2(CO)8 were
performed in [bmim]PF6 either thermally
or in the presence of NMO. For comparison thermal reactions were
done in toluene and NMO-promoted reactions in CH2Cl2. The
results show that the ionic liquid is a suitable substitute for
CH2Cl2. Yields of the NMO-promoted reaction could
be improved by using a two-phase system [bmim]PF6/methylcyclohexane.
Keywords
Pauson-Khand reaction - ionic liquids - amine N-oxides
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