S. Schüßler et al. / Applied Catalysis A: General 445–446 (2012) 231–238
237
The influence of reaction conditions was investigated; the solvent
and the temperature showed the greatest influence due to the solu-
bility of hydrogen in the solvent and the architecture of the support
material. Moreover, it was found that the catalyst is very stable
and easily recyclable lasting ten reaction cycles without any sig-
nificant loss in activity. ICP-MS analysis demonstrated that most of
the initial metal content remained on the support.
Appendix A. Supplementary data
Supplementary data associated with this article can be
Fig. 9. Results for the recycling study for the hydrogenation of cyclohex-2-enone to
cyclohexanone catalyzed by HMDI-cross-linked Pd/chitosan catalyst (p ≈ 0.6 MPa;
50 ◦C; 30 mL ethanol, 100 mg catalyst, reaction time = 0.5 h).
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A Pd containing catalyst was successfully prepared by the assis-
tance of ultrasound, using cross-linked chitosan as the support
material. After the chemical reduction of the Pd(II) ions, the cat-
alyst showed high activity in several hydrogenation reactions.
The selectivity was high, especially for the hydrogenation of ␣,-
unsaturated carbonyl compounds where only the C C double
bond was reduced. Additionally, the hydrogen addition to internal
alkynes and imines was investigated. The reactions were carried
out under mild conditions, using microwave heating techniques.