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notable change were detected, which is indicative of catalyst authentic samples obtained commercially or prepared by reported
stability for at least 5 times reuses. The X-ray diffraction methods.
patterns of the reuse catalyst were found to be similar to the
fresh sample.
All compounds are known and were characterized by
comparison of their physical and spectroscopic data with the
already described in the literatures.
Conclusions
In conclusion, four different silver doped on zinc oxide catalysts
have been prepared and used as catalysts for oxidation reactions
in the atmospheric pressure in solvent-free condition. Good
yields have been observed in oxidation of methylene
compounds, heading to aromatic ketones. Moreover, this
catalyst is an active heterogeneous catalyst in the oxidation of
benzylic C–H bonds.
Acknowledgements
We gratefully acknowledge the support of this work by the
Shiraz University for nancial support.
Notes and references
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Experimental section
All the reagents and materials, including, zinc nitrate
(Zn(NO3)2$6H2O), silver nitrate (AgNO3) and urea were obtained
from Fluka or Merck and used as received without further
purication. The catalyst was characterized using XRD, XPS,
ICP, TEM and BET. The catalyst was characterized by X-ray
diffraction technique using Bruker D8-advance X-ray diffrac-
ꢀ
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nanoparticles was conrmed by Zeiss – EM10C – 80 KV TEM
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and washed with deionized water and absolute ethanol and
ꢂ
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high-temperature furnace.
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1
ucts was conrmed by H NMR, 13C NMR and comparison with
19–26.
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