2
30
M. Ghiaci et al. / Applied Catalysis A: General 393 (2011) 225–230
Table 6
Catalytic activities of THNO and some previously reported catalysts in the cyclohexene oxidation.
◦
Entry
Catalyst
Oxidant
Temperature ( C)
Reaction time (h)
Conversion
Ketone selectivity (%)
Ref.
1
2
3
4
5
6
THNO
Cr MCM-41
4-Alum
Cu amp AMPS
P-Salen-BsdB18C6- (Co–Na)
[Cu(N Oˆ )2]–Y
TBHP
O2
TBHP
TBHP
O2
70
70
8
24
8
8
12
8
98.5
52.2
94.1
63
91.4
90.47
95.0
71.2
82.7
78
41.4
51.00
This work
2
4
5
7
8
Reflux/CH2Cl2
50
70
75
H2O2
was less than 50 nm. Also, the bimetallic and trimetallic mixed
oxides have been synthesized and then used as catalysts in the liq-
uid phase oxidation of cyclohexene using TBHP as the oxidant. The
results show that the incorporation of Ru with Co and Ce enhances
catalytic activity compared to the Ru/Ce and Co/Ce mixed oxides.
Also, we observed that allylic oxidation products predominate and
conversion and selectivity of the products increased when we used
THNO as the catalyst. A maximum of 97.7% cyclohexene conver-
sion with 95% selectivity of 2-cyclohexen-1-one has been achieved
with this new nano-catalyst. The extension of application of this
nano-catalyst to different oxidation reactions is currently under
investigation in our laboratory.
Acknowledgments
Thanks are due to the Research Council of Isfahan University of
Technology and Center of Excellence in the Chemistry Department
of Isfahan University of Technology for supporting of this work.
Fig. 9. Reusability of the catalyst on the oxidation of cyclohexene. Reaction con-
ditions: catalyst: THNO, amount of catalyst: 10 mg, oxidant: 80% aq TBHP, molar
◦
ratio (ox/cyc): 1, reaction temperature: 70 C, solvent: 1,2-dichloroethane (5 mL),
reaction time: 8 h.
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