A dithizone-functionalized polystyrene resin-supported Pd(II) complex as an effective catalyst for Suzuki, Heck, and copper-free Sonogashira reactions under aerobic conditions in water

Article abstract of DOI:10.1016/j.molcata.2013.01.009

A novel polystyrene-supported palladium(II) dithizone complex is found to be a highly active catalyst for the Suzuki, Heck, and Sonogashira reactions of aryl halides in water. By this protocol, aryl halides, coupled with phenyl boronic acid (Suzuki reaction), alkenes (Heck reaction) or terminal alkyne (Sonogashira reaction), smoothly affords the corresponding cross-coupling products in good to excellent yields. Furthermore, the catalyst shows good thermal stability and recyclability. The catalyst was recycled for the Suzuki, Heck, and Sonogashira reactions for five runs without appreciable loss of its catalytic activity and negligible metal leaching.

Full text of DOI:10.1016/j.molcata.2013.01.009

Journal of Molecular Catalysis A: Chemical 370 (2013) 152–159
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A dithizone-functionalized polystyrene resin-supported Pd(II) complex as an
effective catalyst for Suzuki, Heck, and copper-free Sonogashira reactions
under aerobic conditions in water
Mohammad Bakherad∗, Saeideh Jajarmi
School of Chemistry, Shahrood University of Technology, Shahrood, Iran
a r t i c l e i n f o
a b s t r a c t
Article history:
A novel polystyrene-supported palladium(II) dithizone complex is found to be a highly active catalyst for
the Suzuki, Heck, and Sonogashira reactions of aryl halides in water. By this protocol, aryl halides, cou-
pled with phenyl boronic acid (Suzuki reaction), alkenes (Heck reaction) or terminal alkyne (Sonogashira
reaction), smoothly affords the corresponding cross-coupling products in good to excellent yields. Fur-
thermore, the catalyst shows good thermal stability and recyclability. The catalyst was recycled for the
Suzuki, Heck, and Sonogashira reactions for five runs without appreciable loss of its catalytic activity and
negligible metal leaching.
Received 2 June 2012
Received in revised form
10 December 2012
Accepted 15 January 2013
Available online 23 January 2013
Keywords:
Suzuki reaction
Heck reaction
© 2013 Elsevier B.V. All rights reserved.
Sonogashira reaction
Supported catalyst
Recoverable Pd catalyst
Aryl halides
1. Introduction
classes of catalysts or catalyst precursors in the Pd catalyzed C C
bond forming reactions such as Heck-Mizoroki [24–34], Suzuki-
Miyaura [1,35–41], and Sonogashira reactions [42–49].
The immobilization methods used to deposit palladium into het-
erogeneous solid beds have been studied extensively, and diverse
supports such as clay [50], carbon nanofiber [51], montmorillonite
[52], magneticmesoporoussilica [53], zeolite[54], and metal oxides
[55] have been investigated.
A current challenge in this area is the development of effi-
cient immobilized systems that could simultaneously fulfill the
usual targets of achieving high TON values and facilitate recovering
and reuse as well as the need for obtaining Pd-free final products
[56,57], meeting the strict purity specifications for the pharmaceu-
tical industry [58,59].
Regarding the C C bond formation reactions, particular atten-
tion has been paid to the coupling of aryl halides with
organoboronic acids (Suzuki coupling reaction) [1–7], alkenes
(Heck reaction) [8–14], and alkynes (Sonogashira coupling reac-
tion) [15–19], respectively. These Pd-catalyzed coupling reactions
are ranked today among the most general transformations in
organic synthesis, which have great industrial potential for the
synthesis of chemicals, therapeutic drugs, and their intermediates.
The original Heck, Suzuki, and Sonogashira reactions gener-
ally proceed in the presence of a homogeneous palladium catalyst,
which makes its separation and recovery tedious, if not impossible,
and might result in unacceptable palladium contamination of the
products. A way to overcome this difficulty would be the use of a
heterogeneous palladium catalyst.
In this regard, different types of heterogeneous catalysts have
been prepared with the goal of achieving catalyst recovery and
recycling [60,61].
From the standpoint of green chemistry, development of more
environmentally benign conditions for the reaction such as the use
of a heterogeneous palladium catalyst would be desirable [20–23].
Palladacycles have recently emerged as one of the most promising
To date, development of green chemistry through organic reac-
tions conducted in water has become one of the most exciting
research endeavors in organic synthesis [62–65]. Several examples
of Pd-catalyzed Suzuki-Miyaura, Mizoroki-Heck, and Sonogashira
reactions in aqueous media have been reported [66–69].
Recently, Xia et al. described cross-linked polymer supported
Palladium catalyzed carbonylative Sonogashira coupling reaction
in water [70]. Singh et al. reported synthesis and characterization
∗
Corresponding author. Tel.: +98 2733395441; fax: +98 2733395441.
E-mail addresses: m.bakherad@yahoo.com, bakheradm@yahoo.com
(M. Bakherad).
1381-1169/$ – see front matter © 2013 Elsevier B.V. All rights reserved.
http://dx.doi.org/10.1016/j.molcata.2013.01.009

M. Bakherad, S. Jajarmi / Journal of Molecular Catalysis A: Chemical 370 (2013) 152–159
153
of recyclable and recoverable MMT-clay exchanged ammonium
2.1. Preparation of polymer-anchored PS-dtz-Pd(II) 3
tagged carbapalladacycle catalyst for Mizoroki-Heck and Sono-
gashira reactions in ionic liquid media [71]. Furthermore, Iranpoor
et al. illustrated Palladium nano-particles supported on agarose as
efficient catalyst and bioorganic ligand for C C bond formation via
solvent less Mizoroki-Heck reaction and Sonogashira reaction in
polyethylene glycol (PEG 400) [72]. Wu et al. exemplified ionic liq-
uid functionalized phosphine-ligated Palladium complex for the
Sonogashira reactions under aerobic and copper-free conditions
[73]. Above all the methods provide good yield, but some of these
reactions are sluggish requiring at least 24 h for completion, lengthy
work-up procedure, harsh reaction conditions and require abso-
lutely dry and inert media.
To a 250-ml of round bottom flask equipped with a magnetic
stirrer bar and containing DMF (50 ml), were added chloromethy-
lated polystyrene (2 g, 1.25 mmol/g of Cl) and dithizone (7.5 mmol).
The reaction mixture was stirred for 24 h at 100 ◦C, and was sub-
sequently filtered and washed thoroughly with DMF, and dried
in vacuo for 12 h. The dithizone functionalized polymer 2 (3.0 g)
was treated with ethanol (50 ml) for 30 min. An ethanolic solution
of PdCl2(PhCN)2 (1.2 g) was added, and the resulting mixture was
heated to 80 ◦C for 15 h. The resulting bright yellow colored poly-
mer, impregnated with the metal complex, was filtered and washed
with ethanol to obtain PS-dtz-Pd(II) 3 (Scheme 1).
So far, polystyrene-supported palladium catalysts have suc-
cessfully been used for the Heck [74] and Suzuki [75–78]
reactions, and have shown lower levels of palladium leaching
during cross-coupling. To date, a few palladium complexes on
functionalized polystyrene support have been prepared and suc-
cessfully used in Sonogashira reaction [79–85]. Very recently, our
research team have reported the synthesis of the polystyrene-
supported bidenate phosphine palladium(0) complex [abbreviated
as PS-dpp-Pd(0), and the polystyrene-supported palladium(II) 1-
phenyl-1,2-propanedione-2-oxime thiosemi-carbazone complex
[abbreviated as PS-ppdot-Pd(II)], and found that these complexes
are a highly active and recyclable catalyst for Sonogashira reaction
of aryl iodides [86,87] or benzoyl chlorides [88,89] with terminal
alkynes.
2.2. General procedure for the Suzuki coupling reaction
A mixture of aryl halide (1.0 mmol), phenyl boronic acid
(1.2 mmol), PS-dtz-Pd(II) (0.001 mmol), K2CO3 (2 mmol), and water
(3 ml) was stirred at 70 ◦C for 5 h. After completion of the reac-
tion, the mixture was filtered to recover the catalyst. The polymer
was washed with water and acetonitrile, vacuum dried, and stored
for a new run. After GC analysis, the solvent was removed under
vacuum, and the crude product was subjected to silica gel column
chromatography using CHCl3 CH3OH (97:3) as eluent to afford the
pure product.
2.3. General procedure for the Heck reaction
Our approach was guided by three imperatives: (i) the sup-
port should be easily accessible; (ii) develop an efficient synthetic
process for the facile conversion of Heck, Suzuki, and Sonogashira
coupling reactions; and (iii) the ligand anchored on the support
should be thermal stability, air-stable at room temperature, which
should allow its storage in normal bottles with unlimited shelf-life.
Herein, we report the synthesis of polystyrene-supported palla-
dium(II) dithizone complex [abbreviated as PS-dtz-Pd(II)] catalyst
and its application to cross-couplings such as Suzuki-Miyaura,
Mizoroki-Heck, and copper-free Sonogashira reactions in water
under aerobic conditions. The ease of preparation of the complex,
its long shelf-life, stability toward air, and compatibility with a
wide variety of aryl halides and alkynes make it ideal for the above
mentioned reactions.
A mixture of aryl halide (1.0 mmol), methyl acrylate (1.5 mmol),
PS-dtz-Pd(II) (0.001 mmol), K2CO3 (2.0 mmol), and water (3 ml)
was stirred at 70 ◦C for 5 h. After completion of the reaction, the
mixture was filtered to recover the catalyst. The polymer was
washed with water and acetonitrile, vacuum dried, and stored for
a new run. After GC analysis, the solvent was removed under vac-
uum, and the crude product was subjected to silica gel column
chromatography using CHCl3 CH3OH (97:3) as eluent to afford the
pure product.
2.4. General procedure for the Sonogashira coupling reaction
An aryl halide (1.0 mmol) and a terminal alkyne (1.2 mmol)
were added to a mixture of PS-dtz-Pd(II) (0.001 mmol), piperidine
(2.0 mmol), and water (3 ml) in a glass flask under vigorous stirring.
The mixture was stirred at room temperature for 3 h under aerobic
conditions. After completion of the reaction, the mixture was fil-
tered to recover the catalyst. The polymer was washed with water
and acetonitrile, vacuum dried, and stored for a new run. After GC
analysis, the solvent was removed under vacuum, and the crude
2. Experimental
All materials were commercial reagent grade. Chloromethylated
polystyrene (4–5% Cl and 2% cross-linked with divinylbenzene)
was a product of Merck. Alkyne and aryl halide compounds were
obtained from Merck or Fluka.
S
S
H
DMF, 100 oC, 20 h
N
N
N
Cl
+
N
H
N
Ph
Ph
PhHN N
N Ph
1
2
[PdCl2(PhCN)2]
EtOH, reflux, 15 h
S
N
PhHN N
N
Ph
Pd
Cl
Cl
3
Scheme 1. Preparation of the heterogeneous catalyst PS-dtz-Pd(II) 3.

154
M. Bakherad, S. Jajarmi / Journal of Molecular Catalysis A: Chemical 370 (2013) 152–159
Fig. 1. FT-IR spectra of: (A) chloromethylated polystyrene (B) polystyrene-dithizone ligand (C) supported Pd-dithizone complex.

M. Bakherad, S. Jajarmi / Journal of Molecular Catalysis A: Chemical 370 (2013) 152–159
155
product was subjected to silica gel column chromatography using
CHCl3 CH3OH (97:3) as eluent to afford the pure product.
3. Results and discussion
3.1. Characterization of PS-dtz-Pd(II)
A polystyrene divinylbenzene resin anchored with a chelating
regent dithizone has been reported by Grote and Kettrup [90]. They
have used this support for the sorption of gold and platinum group
metals and base metals like copper, nickel, and zinc.
We report here anchoring of dithizone on crosslinked
polystyrene polymer (Scheme 1). The chelating polymeric matrix
is further used for Suzuki, Heck, and Sonogashira reactions. A
polystyrene resin (2% DVB) functionalized with dithizone groups
was formed by heating a mixture of chloromethylated polystyrene
and dithizone in DMF at 100 ◦C for 24 h. The polymer-supported
dithizone is insoluble in common organic solvents. Reaction of
polymer-bound dithizone with a solution of [PdCl2(C6H5CN)2] in
ethanol under reflux conditions resulted in covalent attachment of
palladium onto functionalized polymer. The N content of resin was
obtained to be 2.8% (1.98 mmol/g), which indicates that only 40% of
total chlorines was substituted by amine). The amount of palladium
incorporated into the polymer was also determined by inductively
coupled plasma (ICP), which showed the value of about 3.1%.
The difference in the amount of chlorine in chloromethylated
polystyrene and the dithizone anchored support is due to the chem-
ical binding of dithizone to the support by chlorine displacement.
This was further confirmed through FT-IR analysis of the copolymer
and copolymer loaded with dithizone.
In the FT-IR spectrum of polymer-bound dithizone, the sharp
Cl peak (due to CH2Cl groups) at 1265 cm−1 (Fig. 1A) in
Fig. 2. Scanning electron micrograph of (a) chloromethylated polystyrene; (b) PS-
dtz-Pd(II) complex.
C
the starting polymer was practically omitted or seen as a weak
band after introduction of dithizone on the polymer. The stretch-
ing vibrations of the C N double bonds appear at 1672 cm−1 for
polystyrene-dithizone ligand, respectively (Fig. 1B). The NH group
of polystyrene-dithizone in the IR spectrum is 3395 cm−1, whereas
the NH group of dithizone palladium complex (Fig. 1C) in the IR
spectrum is 3402 cm−1 indicating that the Pd-N bond has been
established.
Scanning electron micrographs (SEM) were reported for a single
bead of pure chloromethylated polystyrene, and polymer-anchored
complex to observe the morphological changes. As expected, the
pure polystyrene bead had a smooth and flat surface, while the
anchored complex showed roughening of the top layer (Fig. 2).
the optimal reaction conditions in hand, we firstly explored the
scope and limitations of the reaction with a set of aryl iodides and
phenylboronic acid. We were pleased to find out that all reactions
afforded the desired coupling products 6 in excellent yields within
5 h, and the substituents, either an electron-donating group such as
methoxy group (Table 2, entry 7) or an electron-withdrawing group
such as Cl, NO2, or COMe on the phenyl ring of 4 had almost no sig-
nificant effect on these reactions (Table 2, entries 3–6). To extend
the scope of our work, we next investigated the coupling reaction
of various aryl bromides with phenyl boronic acid. The less reactive
Table 1
3.2. Catalytic activity
Optimization of the conditions for Suzuki reaction of iodobenzene with phenyl
boronic acidea.
HO
Efficiency of the dithizone-functionalized polystyrene resin-
supported Pd(II) complex 3 was tested in Suzuki, Heck, and
Sonogashira reactions.
PS-dtz-Pd(II)
base, H2O, 70 oC
I
B
+
HO
4a
5
6a
3.2.1. Catalytic Suzuki cross-coupling reactions
Entry
Base
Cat (mol%)
Yield (%)b
In the initial investigations, we examined the Suzuki-Miyaura
coupling reaction of the model substrate phenyl iodide 4a with
phenylboronic acid 5 using PS-dtz-Pd(II) complex (0.1 mol%) as the
catalyst in water at 70 ◦C for 5 h (Table 1). As it can be seen in Table 1,
from the bases screened, K2CO3 showed the best result, and the cor-
responding coupling product 6a was obtained in 99% yield (Table 1,
entry 8). Effect of temperature on the activity of PS-dtz-Pd(II) com-
plex was also studied. As the temperature decreased from 70 to
25 ◦C, the yield of product 6a decreased from 99% to 60% (entry 9).
A low palladium concentration gave a decreased yield (entry 10).
Thus at the optimal reaction conditions PS-dtz-Pd(II) complex
(0.1 mol%) as the catalyst, K2CO3 (2.0 equiv) as the base, and water
(3 ml) as the solvent are used at the temperature of 70 ◦C. With
1
2
3
4
5
6
7
8
Et3N
DIEA
0.1
0.1
0.1
0.1
0.1
0.1
0.1
0.1
0.1
0.05
95
90
86
94
90
93
95
99
60
90
Pyridine
Piperidine
Pyrrolidine
KOH
Na2CO3
K2CO3
9c
10
K2CO3
K2CO3
a
Conditions: iodobenzene (1.0 mmol), phenylboronic acide (1.2 mmol), base
(2.0 mmol), H2O (3 ml), 5 h at 70 ◦C.
b
GC yield.
Reaction at 25 ◦C.
c

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M. Bakherad, S. Jajarmi / Journal of Molecular Catalysis A: Chemical 370 (2013) 152–159
Table 2
unactivated aryl bromides such as p-methoxybromobenzene gave
80% yield (entry 7).
Suzuki reaction of aryl halides with phenyl boronic acid using PS-dtz-Pd(II)
complexa.
OH
PS-dtz-Pd(II)
X
Ph
B
+
Ph
3.2.3. Catalytic Sonogashira reactions
K2CO3, H2O, 70 oC
OH
R
We next investigated the PS-dtz-Pd(II) complex catalytic system
for the copper-free Sonogashira cross-coupling reaction. The cat-
alytic activity of the PS-dtz-Pd(II) complex 3 (0.1 mol%) was studied
at room temperature under aerobic conditions in a copper-free
Sonogashira reaction using phenylacetylene and aryl halides in the
presence of various bases in water. Our optimization data is shown
in Table 4.
When the reaction of phenylacetylene with phenyl iodide was
performed with piperidine as base, an excellent 99% yield of the
product was obtained (entry 4). Since aryl bromides are cheaper
and more readily available than aryl iodides, and hence are synthet-
ically more useful as educts, we examined the reaction of phenyl
bromide with phenylacetylene under the above conditions, and
piperidine was found to be the best choice of base amongst those
tested (entry 13).
After the optimized conditions were found, we explored the
general applicability of the PS-dtz-Pd(II) complex 3 as a catalyst
for copper-free coupling of different alkynes 9 with aryl iodides
and bromides 4 containing electron withdrawing or donating
substituents. The results are shown in Table 5. The coupling of
phenylacetylene with iodobenzene took place smoothly at room
temperature in the presence of piperidine (2 mmol) and 0.1 mol%
palladium of the PS-dtz-Pd(II) complex 3 to give an excellent yield
of diphenylacetylene (entry 1). The Sonogashira coupling of pheny-
lacetylene with p-iodoanisol bearing electron-donating groups at
their p-positions gave the corresponding biarylacetylenes 10g in
97% yield, (entry 7). p-Nitroiodobenzene, and m-nitroiodobenzene,
having electron-deficient aromatic rings, also underwent the Sono-
gashira coupling with phenylacetylene under similar conditions to
afford the corresponding biarylacetylenes 10b, and 10c in excellent
yields (100%) (entries 2 and 3).
When the less reactive acetylene, 1-hexyne, and propargyl alco-
hol were used, the coupling product was produced efficiently.
Coupling of p-substituted iodobenzene having nitro, chloro, bromo,
and methoxy groups took place with 1-hexyne to give the cor-
responding products 10i–m in excellent yields (entries 9–13).
Propargyl alcohol also reacted efficiently with aryl iodides provid-
ing excellent yields of the desired products (entries 14–16).
To extend the scope of our work, we next investigated the
coupling of various aryl bromides with terminal alkynes. As shown
in Table 5, high catalytic activity was observed in the coupling of
unactivated aryl bromides such as nitrobromobenzenes (entries
18, 19, 24, 25, and 29) and p-bromoanisole (entries 22, 27, and
30) as well as the activated nitroiodobenzenes (entries 2, 3, 9,
10, and 15) and p-iodoanisol (entries 7, 13, and 16). Moreover,
R
4
5
6
Entry
R
X
Product
Yield (%)b
TON
1
2
3
4
5
6
7
8
9
H
4-Br
4-Cl
I
I
I
I
I
I
I
Br
Br
Br
Br
Br
Br
6a
6b
6c
6d
6e
6f
6g
6a
6h
6i
99
98
99
100
100
100
98
68
92
90
80
990
980
990
1000
1000
1000
980
680
920
900
800
4-MeCO
4-NO2
3-NO2
4-MeO
H
4-CHO
4-CN
4-NO2
3-NO2
4-MeO
10
11
12
13
6e
6f
6g
90
60
900
600
a
Reaction conditions: aryl halide (1.0 mmol), phenyl boronic acid (1.2 mmol),
K2CO3 (2.0 mmol), PS-dtz-Pd(II) (0.001 mmol), H2O (3 ml), 5 h at 70 ◦C.
b
GC yield.
bromobenzene showed low yield (entry 8). However, the acti-
vated aryl bromides, 4-bromobenzaldehyde, 4-bromobenzonitrile,
4-nitrobromobenzene and 3-nitrobromobenzene gave the corre-
sponding product in high yield (Table 2, entries 9–12).
3.2.2. Catalytic Heck reaction
The scope of this methodology was further extended for Heck
reaction. Using PS-dtz-Pd(II) complex as catalyst bases like K2CO3
(94%), KOH (93%), Et3N (97%), diisopropylethylamine (92%), pyri-
dine (85%), and piperidine (87%), in water at 70 ◦C were screened for
the standard reaction. It was observed that the reaction was more
favorable using Et3N as the base, and the protocol was applied for
coupling of methylacrylate with aryl halides.
Using the optimized reaction conditions, we explored the gen-
eral applicability of PS-dtz-Pd(II) complex with methyl acrylate
and aryl halides containing electron withdrawing or donating
substituents, and the results were tabulated in Table 3. Among
the various substituted aryl iodides, both deactivated (electron-
rich) and activated (electron-poor) examples were converted
efficiently to the desired products in excellent yields (entries 1–4).
As expected, aryl iodides were more reactive than aryl bromides,
and the substituent effects in the aryl iodides appeared to be
less significant than in the aryl bromides. As shown in Table 3,
activated aryl bromides such as p-nitrobromobenzene underwent
the Heck reaction with methyl acrylate under similar conditions to
afford the corresponding product in 95% yield (entry 6) whereas,
Table 3
Heck reactions of aryl halides with methyl acrylate using PS-dtz-Pd(II) complexea.
CO2Me
CO2Me
PS-dtz-Pd(II)
R
X
+
R
Et3N, H2O, 70 oC
4
7
8
Entry
R
X
Product
Yield(%)b
TON
1
2
3
4
5
6
7
H
Cl
I
I
I
I
Br
Br
Br
8a
8b
8c
8d
8a
8c
8d
97
98
98
95
90
95
80
970
980
980
950
900
850
800
NO2
MeO
H
NO2
MeO
a
Conditions: aryl halide (1.0 mmol), methyl acrylate (1.5 mmol), PS-dtz-Pd(II) (0.001 mmol), Et3N (2.0 mmol), H2O (3 ml), 5 h at 70 ◦C.
GC yield.
b

M. Bakherad, S. Jajarmi / Journal of Molecular Catalysis A: Chemical 370 (2013) 152–159
157
Table 4
Copper-free Sonogashira reaction of phenylacetylene with aryl halides in the presence of different basesa.
PS-dtz-Pd(II)
+
X
Base, H2O, r.t.
9a
10a
Entry
X
Base
Yieldb (%)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
I
I
I
I
I
I
I
I
DIEA
Et3N
80
96
52
99
42
64
97
95
93
60
75
53
99
55
43
95
90
87
Pyridine
Piperidine
Pyrrolidin
Butylamin
K2CO3
Na2CO3
KOH
DIEA
I
Br
Br
Br
Br
Br
Br
Br
Br
Br
Et3N
Pyridine
Piperidine
Pyrrolidin
Butylamin
K2CO3
Na2CO3
KOH
a
Reaction conditions: phenylacetylene (1.2 mmol), halobenzene (1.0 mmol), base (2.0 mmol), PS-dtz-Pd(II) (0.001 mmol), H2O (3 ml), 3 h at room temperature, aerobic
conditions.
b
GC yield.
Table 5
Copper-free Sonogashira reactions of terminal alkynes with aryl halidesa.
PS-dtz-Pd(II)
R1
R1
+
X
piperidine, H2O, r.t.
R
R
9
4
10
Entry
R
X
Y
Product
Yieldb (%)
TON
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
Ph
Ph
Ph
Ph
Ph
Ph
Ph
n-C4H9
n-C4H9
n-C4H9
n-C4H9
n-C4H9
n-C4H9
CH2OH
CH2OH
CH2OH
Ph
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
Br
Br
Br
Br
Br
Br
Br
Br
Br
Br
Br
Br
Br
Br
H
10a
10b
10c
10d
10e
10f
10g
10h
10i
99
100
100
99
99
99
97
98
100
100
99
98
98
99
100
98
97
98
97
97
96
92
96
97
97
96
95
92
92
90
990
1000
1000
990
990
990
970
980
1000
1000
990
980
980
990
1000
980
970
980
970
970
960
920
960
970
970
960
950
920
920
900
4-NO2
3-NO2
4-Cl
4-Br
4-COCH3
4-OCH3
H
4-NO2
3-NO2
4-Cl
4-Br
4-OCH3
H
4-NO2
4-OCH3
H
4-NO2
3-NO2
4-Cl
4-F
4-OCH3
H
10j
10k
10l
10m
10n
10o
10p
10a
10b
10c
10d
10q
10g
10h
10i
Ph
Ph
Ph
Ph
Ph
n-C4H9
n-C4H9
n-C4H9
n-C4H9
n-C4H9
CH2OH
CH2OH
CH2OH
4-NO2
3-NO2
4-Cl
4-OCH3
H
10j
10k
10m
10n
10o
10p
4-NO2
4-OCH3
a
Reaction conditions: aryl halide (1.0 mmol), terminal alkyne (1.2 mmol), PS-dtz-Pd(II) (0.001 mmol), piperidine (2.0 mmol), H2O (3 ml), 3 h, room temperature, aerobic
conditions.
b
GC yield.

158
M. Bakherad, S. Jajarmi / Journal of Molecular Catalysis A: Chemical 370 (2013) 152–159
Table 6
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1
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99
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b
GC yield.
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Acknowledgement
We gratefully acknowledge the financial support of the Research
Council of Shahrood University of Technology.

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