2
76
Y. Ding et al.
Table 3 Hydrogenation of nitrobenzene derivatives with different
substituents at the phenyl ring with the Ru/CMK-3 catalyst
RuCl as Ru precursor. The Ru nanoparticles entrapped in
3
OMCs worked well for the liquid-phase hydrogenation of
benzaldehyde and its derivatives under the tested condi-
tions (medium hydrogen pressure, water as solvent, at room
temperature). The Ru/CMK-3 catalyst showed good per-
formance as well in the liquid-phase hydrogenation of
nitrobenzene and its derivatives under optimal conditions,
especially for those with an electron-donating group at
ortho- or para-position. Notably, the Ru/CMK-3 catalyst
was more efficient than the commercial Ru/C catalyst and
the homemade Ru catalyst supported on activated carbon
under the same conditions for the liquid-phase hydroge-
nation of benzaldehyde. The Ru nanoparticles could be
well stabilized by the ordered mesoporous carbons so that
the Ru/CMK-3 catalyst could also be easily recovered and
reused for several times.
NO2
NH2
Ru Catalyst
R
R
Solvent, H2, 323 K
-1
Entry R group Solvent
Conversion TOF (h
a
)
(
%)
1
2
3
4
5
6
7
8
9
1
1
1
1
1
2-Cl
18 mL W ? 2 mL E
20 mL E
21.6
32.9
26.1
69.2
14.6
35.2
88.4
134.7
106.8
283.3
59.8
2-Cl
3-Cl
18 mL W ? 2 mL E
20 mL E
3-Cl
4-Cl
18 mL W ? 2 mL E
20 mL E
4-Cl
144.1
409.4
153.9
409.4
384.0
98.6
2-MeO
4-MeO
4-MeO
18 mL W ? 2 mL E 100
18 mL W ? 2 mL E
20 mL E
37.6
100
93.8
0
1
2
3
4
2-CH
3-CH
3-CH
4-CH
4-CH
3
3
3
3
3
18 mL W ? 2 mL E
18 mL W ? 2 mL E
20 mL E
Acknowledgments This work was supported by the National Nat-
ural Science Foundation of China (21273076 and 20925310) and
Shanghai Leading Academic Discipline Project (B409). Finally,
helpful comments have been made by the reviewers, and some of
these were followed in the revision.
24.1
45.6
43.2
65.6
186.7
176.8
268.5
18 mL W ? 2 mL E
20 mL E
Reaction conditions: 0.05 g 5.0 wt% Ru catalyst; 8.1 mmol sub-
strates; 4.0 MPa H , 2.5 h; 323 K; 1,200 rpm
W water, E ethanol
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4
Conclusion
The 5 wt% Ru/CMK-3 catalyst was prepared via a facile
impregnation method using an aqueous solution containing
1
23