610
D. Yuan et al. / Catalysis Communications 11 (2010) 606–610
The novel magnetic catalyst is stable and shows high catalytic
100
80
60
40
20
0
activity in promoting Heck cross-coupling reaction. In addition,
the novel catalyst can be easily recovered by using a permanent
magnet and reused at least six times without significant loss of
its catalytic activity and selectivity. As a consequence, magnetic
composite microspheres prepared by soap free emulsion can be
ideal supports for immobilization of industrial homogeneous cata-
lyst. Further studies on the effects of magnetic composite micro-
spheres properties on the catalytic activity of the immobilized
catalyst as well as the application of the novel catalyst to other pal-
ladium catalyst reactions are now in progress.
1
2
3
4
5
6
Appendix A. Supplementary data
reused times
a
Supplementary data associated with this article can be found, in
Fig. 5. Recycle of the Fe3O4/P (GMA–MMA–AA)–Pd(0)1
.
References
purification. As shown in Fig. 5a, the novel catalyst can be reused at
least six times only with a slight loss of activity for the Heck reac-
tion of iodobenzene and acrylic acid.
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4. Conclusions
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1
Reactions were carried out with the magnetic catalyst (0.5 mol% Pd), iodobenzene
(5 mmol), acrylic acid (7.5 mmol), Bu3N (10 mmol), DMF (5 ml) at 95 °C in the air,
reaction time (3 h).