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solid product was filtered and washed with an HCl/H2O mixture
Recycling procedure for the Suzuki reaction
The white solid was calcined at 5508C for 5 h in air.
In a round-bottom flask, catalyst 6 (0.1 mol%, 10 mg), 4-bromo-
benzaldehyde (10 mmol), phenylboronic acid (11 mmol), K2CO3
(12 mmol), ethanol (12 mL), and water (12 mL) were placed. The re-
action mixture was stirred at 508C for 19 h. Then, it was allowed to
cool down, filtered under reduced pressure, and after that extract-
ed and purified as in the typical procedure for the Suzuki reaction.
The catalyst was washed with water, dichloromethane, and dried
at 408C overnight, to be subsequently reused in the next cycles.
Procedure for the synthesis of modified silica SBA-15
In a round-bottom flask SBA-15 (2.0 g), 3-(mercaptopropyl)-trime-
thoxysilane (0.016 mol) and toluene (15 mL) were placed. The sus-
pension was heated at reflux for 24 h. Then, the suspension was
cooled down, filtered, and washed with methanol. The white
powder was dried in an oven at 808C overnight.
General procedure for “hot filtration” and “room-tempera-
ture” Suzuki reaction
Procedure for the synthesis of material 3
In a two-necked round-bottom flask 3-mercaptopropyl modified
SBA-15 (1.0 g, SH loading 0.9 mmolgÀ1, 0.9 mmol), bisvinylthiazoli-
um salt (3.69 equiv.), ethanol (32.4 mL), and azobisisobutyronitrile
were placed. The suspension was degassed by bubbling nitrogen
for 30 min. The reaction mixture was heated in an oil bath at 788C
under nitrogen, and stirred for 20 h. After cooling to RT, the mix-
ture was filtered and the solid washed with methanol in a soxhlet
system for 48 h. Then, the obtained material 3 was dried in an
oven at 408C overnight. Elemental analysis of material 3: N% (3.2),
C% (28.2), H% (3.9), S% (6.9).
In a round-bottom flask, catalyst 6 (0.1 mol%, 1 mg), phenylboron-
ic acid (138 mg, 1.1 mmol), K2CO3 (167 mg, 1.2 mmol), 3-bromoace-
tophenone (0.134 mL, 1 mmol), ethanol (1.2 mL), and water
(1.2 mL) were placed. The reaction mixture was heated at 508C for
4 h to be subsequently filtered (in the case of hot filtration) or
cooled at RT and then the catalyst was separated from the reaction
mixture by means of a syringe filter. Then, the mixture was heated
at 508C for 15 h. After that, it was allowed to cool down, water
was added, and the mixture extracted with dichloromethane (3
30 mL). The organic phase was dried with Na2SO4, filtered, and con-
centrated under reduced pressure. The residue was purified with
a short plug of silica under vacuum using hexane/ethyl acetate as
eluent.
Typical procedure for the synthesis of the palladium catalyst
6
In a round-bottom flask were placed PdCl2 (49.8 mg, 0.281 mmol),
NaCl (312 mg, 5.342 mmol), and water (6.8 mL). The flask was
heated at 808C until the PdCl2 was dissolved. This clear orange so-
lution was cooled at RT and added to a suspension of material 3
(250 mg) in water (2.25 mL). The suspension was stirred at RT for
20 h, then filtered under reduced pressure, washed with water and
dried overnight under reduced pressure at RT. The material was
suspended in anhydrous ethanol (6 mL) and to this suspension
a solution of NaBH4 (72 mg, 1.903 mmol, 7 equiv) in anhydrous eth-
anol (6 mL) was added dropwise. The suspension turned black and
was stirred at RT for 6 h, then filtered under reduced pressure,
washed with water and ethanol, and dried at RT.
Acknowledgements
We gratefully acknowledge the Università degli Studi di Palermo,
the Università degli Studi di Perugia, the University of Namur for
financial support. The authors thank Dr. P. Louette and Dr L.
Fusaro for their support in XPS and NMR analysis, respectively.
Keywords: CÀC coupling
· heterogeneous catalysis · N
ligands · palladium · S ligands
[1] a) A. De Meijere, F. Diederich, Metal-Catalyzed Cross-Coupling Reactions,
2004; b) E. Negishi, Handbook of Organopalladium Chemistry for Organic
Synthesis, 2002; c) K. C. Nicolaou, P. G. Bulger, D. Sarlah, Angew. Chem.
Typical procedure for the Suzuki reaction
In a round-bottom flask, catalyst 6 (0.1 mol%, 1 mg), phenylboron-
ic or 4-formylphenylboronic acid (1.1 mmol), K2CO3 (167 mg,
1.2 mmol), the aryl halide (1 mmol), ethanol (1.2 mL), and water
(1.2 mL) were placed. The reaction mixture was stirred at 508C.
After 19 h, the reaction mixture was cooled down, then water was
added and the mixture extracted with dichloromethane (3
30 mL). The organic phase was dried with Na2SO4, filtered, and con-
centrated under reduced pressure and the residue passed through
a short silica pad (petroleum ether/ethyl acetate).
Beller, Adv. Synth. Catal. 2009, 351, 3027–3043.
c) Y. Lim, Y. S. Park, Y. Kang, D. Y. Jang, J. H. Kim, J. J. Kim, A. Sellinger,
Polym. Sci. Part A 2001, 39, 1533–1556; e) J. Sakamoto, M. Rehahn, G.
[4] a) . Molnµr, Palladium-Catalyzed Coupling Reactions: Practical Aspects
and Future Developments, 2013; b) A. Molnµr, Chem. Rev. 2011, 111,
Typical procedure for the Heck reaction
To a round-bottom flask, catalyst 6 (0.1 mol%, 1 mg), alkene
(1.5 mmol), aryl iodide (1 mmol), triethylamine (2 mmol), and DMF/
H2O (4 mL+1 mL) were added. The reaction mixture was heated at
908C for 16 h. Then, the reaction mixture was cooled at RT, diluted
with water and extracted with dichloromethane (330 mL). The or-
ganic phase was dried with Na2SO4, evaporated under reduced
pressure and the residue passed through a short silica pad (petro-
leum ether/ethyl acetate).
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