1
6
K.M. Parida et al. / Journal of Molecular Catalysis A: Chemical 342–343 (2011) 11–17
Scheme 2. The possible mechanistic pathway for Suzuki coupling using Au(III) Schiff-base complex.
no change in catalytic activity even after fourth recycle. From
atomic absorption spectroscopy (AAS) analysis it was found that
metal content of the recycled catalyst remained unaltered indi-
cating no leaching of the metal from MCM-41. In this context,
the catalyst was removed from the solution after approximately
Acknowledgements
The authors are extremely thankful to Professor B.K. Mishra,
Director, IMMT, Bhubaneswar 751013, Orissa, India, for his con-
stant encouragement and permission to publish the paper. The
authors are also thankful to DST, New Delhi for financial support.
5
0% conversion at the reaction temperature. The isolated solution
did not exhibit any further reactivity under similar reaction con-
ditions. These studies indicate that the loss of Au active site is
negligible, which could account for the preservation of catalytic
activity. IR spectra for the recycled catalyst has provided along
with the fresh catalyst in Fig. 3d. Similar spectra suggest retention
of all types of properties of the recycled catalyst to that of fresh
catalyst.
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