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H. Jiang et al.
halide in the absence of organic solvent. A variety of aryl
bromides and iodides were cyanated smoothly with a wide
range of substrate scope in good-to-excellent yields. The
excellent catalytic performance in water and the easy
separation and reuse of the catalyst make it a useful
alternative to other heterogeneous catalysts system.
Table 3 Recyling of the catalyst in the cyanation reaction
K [Fe(CN) ]
, K2CO3 , cat.
6
4
I
CN
H2O , 2%TX100
Entry
Cycle
Yielda (%)
1
2
3
4
5
1st
95
93
91
89
85
2nd
3nd
4th
5th
Acknowledgments Financial support from National Nature Science
Foundation of China (No. 20901032); China Scholarship Council; the
Fundamental Research Funds for the Central Universities (No. JUS-
RP11005, JUSRP211A09) and the Natural Science Foundation of
Jiangnan University (No. 2008LYY005, 2007LQN12, and 20071789)
is acknowledged.
Reaction conditions: iodobenzene (1.0 mmol), K4[Fe(CN)6] (0.3
mmol), K2CO3 (0.3 mmol), TX100 (2 wt%), and catalyst (0.5 mol%
of Pd) was added initially in 5 ml water, 100 °C
a
Yield determined by GC and GC/MS analysis, based on
iodobenzene
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After completion of the reaction, the mixture was cooled to
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In summary, we have developed a polymer-supported
Schiff base palladium complex for the cyanation of aryl
123