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reductive synthesis of nanoparticles is applicable to a wide
range of catalytically active transition metals, which can be
readily inserted into GNF nanoreactors using the methodology
described for CuNP in this study. Our findings broaden the
spectrum of preparative chemical transformations in carbon
nanoreactors which present an ideal catalyst system for further
exploration of the effects of nanoscale confinement on chemical
processes, ensuring high selectivity, activity and recyclability of
catalytic centres. Current development of nanotubes and hollow
nanofibres as nanoreactors is very timely, as their recently
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3
demonstrated applications as magnetically controlled pipettes,
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4
25
liquid chromatographers and cellular endoscopes are funda-
mentally changing the way chemists study and make molecules.
The authors thank the ERC for supporting this research, the
NNNC for access to TEM facilities and Mr Ahmed Alhadrami
and Mr Scott Miners for technical assistance.
Scheme 1 The retention of high catalytic activity after multiple cycles using
CuNP@GNF nanoreactors containing catalyst.
Notes and references
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5,16
Thirdly and most significantly, the recyclability of CuNP@GNF
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thus explaining the subtle variation in absolute activity across
catalytic cycles, but critically remain anchored to the interior of
GNF and are therefore available for subsequent reactions
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In conclusion, we have shown for the first time that carbon
nanoreactors provide an excellent environment for cycloaddi-
tion reactions. The kinetics of reactions are accelerated and
conversion rates improved in nanoreactors relative to catalysts
deposited on the outer surfaces. Most significantly, catalytic
centres embedded in the nanoreactor cavity are stabilised by
interactions with the nanoscale graphitic step-edges, which
prevent the loss of catalyst during reactions, thus allowing
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This journal is c The Royal Society of Chemistry 2013
Chem. Commun., 2013, 49, 1067--1069 1069