PAPER
Palladium Nanoparticles in Polymers as Catalyst
3793
grease-free high-vacuum stopcock. The flask was filled with argon.
After stirring at 70 °C for 2 h, the mixture was filtered through a
glass filter. The filtrate was evaporated under reduced pressure. The
crude residue was purified by column chromatography to give 1-(al-
lyloxy)naphthalene; yield: 183 mg (99%).
In summary, we have developed a simple method for pre-
paring a polymer-supported palladium catalyst from
readily available reagents, and demonstrated their high
catalytic activities in the hydrogenations of alkynes and
alkenes, carbon–carbon cross-coupling reactions, and aer-
obic alcohol oxidation.
Aerobic Oxidation of Benzyl Alcohol
To a solution of benzyl alcohol (108 mg, 1.00 mmol) in toluene (5
mL), was added 1 (37.0 mg, 0.5 mol% Pd), and the mixture was
heated at 80 °C for 9 h under air. The catalyst was filtered and
washed with acetone.
Catalyst 1
Pd(PPh3)4 (99.4 mg, 0.086 mmol), butan-1-ol (64.0 mg, 0.864
mmol), styrene (809 mg, 7.77 mmol), divinylbenzene (102 mg,
0.432 mmol) and THF (870 mg, 12.0 mmol) were added to a 50 mL
round bottom flask equipped with condenser. The mixture was
stirred at 90 °C for 6 h. After cooling to r.t., AIBN (2.80 mg, 0.017
mmol) was added. The mixture was further stirred at 90 °C for 6 h.
The catalyst was crushed into a gray powder. The catalyst was col-
lected by filtration, washed with THF (10 mL), filtered,13 and dried
at r.t. in the air. The palladium catalyst 1 was obtained as a gray
powder; yield: 640 mg (1.43 wt% of Pd).
Acknowledgment
We are grateful for the financial supports from KOSEF through the
Center for Integrated Molecular System, and the Korean Ministry of
Education through the BK21 project for our graduate program.
References
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Hydrogenation of trans-Stilbene
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lyst was filtered and washed with Et2O. Removal of volatiles from
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filled with argon. After stirring at 50 °C for 12 h, the mixture was
filtered through a glass filter. The filtrate was evaporated under re-
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Coupling of Methyl 4-Iodobenzoate with Styrene
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110 °C for 20 h, the mixture was filtered through a glass filter. H2O
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Allylation Reaction; 1-(Allyloxy)naphthalene; Typical Proce-
dure
Allyl methyl carbonate (116 mg, 1.00 mmol), 1-naphthol (144 mg,
1.00 mmol), Ph3P (53.0 mg, 0.2 mmol), 1 (74.0 mg, 1.0 mol% Pd),
and THF (5 mL) were added to a 25 mL flask equipped with a
Synthesis 2006, No. 22, 3790–3794 © Thieme Stuttgart · New York