1124
Surjyakanta Rana et al.
selectivity of 50CsPTA/MCM-41 was due to higher Acknowledgements
number of acid sites and surface area.
The authors are thankful to Prof. B K Mishra Direc-
tor Institute of Materials and Materials Technology
IMMT), Bhubaneswar for the constant encouragement
and permission to publish this paper. One of the authors
SR is grateful to the Council of Scientific and Industrial
Research (CSIR) New Delhi, for the award of SRF.
The conversion was only 5% without catalyst, sug-
gesting the influence of solid acid catalyst on the
conversion. Several organic substrates including phe-
nol were subjected to the acetylation reaction using
(
5
0CsPTA/MCM-41 as catalyst and the results are sum-
marized in table 2. The presence of electron with-
drawing substituents (nitrogroup and halo group) on the
aromatic ring substantially decreases the rate of acety-
lation while an electron-donating group (-CH , -OCH ,
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. Conclusions
Phosphotungstic acid and its cesium and potassium
salts supported on MCM-41 are found to be very
active and an efficient catalyst for acetylation of aro-
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Supporting material
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Website.
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