Carboxymethylcellulose-supported palladium nanoparticles generated in situ from palladium(II) carboxymethylcellulose as an efficient and reusable catalyst for ligand- and base-free Heck-Matsuda and Suzuki-Miyaura couplings

Article abstract of DOI:10.1002/aoc.3346

A novel palladium(II) carboxymethylcellulose (CMC-Pd^II) was prepared from sodium carboxymethylcellulose (CMC-Na) and PdCl₂ in aqueous solution. It was employed as precatalyst for Heck-Matsuda and Suzuki-Miyaura couplings. The true catalytic species are active soluble Pd(0) or Pd(0) clusters released from palladium nanoparticles deposited on the CMC molecular skeleton (CMC-Pd⁰) formed in situ from CMC-Pd^II in the catalytic process.

Full text of DOI:10.1002/aoc.3346

Full paper
Received: 28 April 2015
Revised: 31 May 2015
Accepted: 1 June 2015
Published online in Wiley Online Library: 27 July 2015
(wileyonlinelibrary.com) DOI 10.1002/aoc.3346
Carboxymethylcellulose-supported palladium
nanoparticles generated in situ from
palladium(II) carboxymethylcellulose as an
efficient and reusable catalyst for ligand- and
base-free Heck–Matsuda and Suzuki–
Miyaura couplings
Jinlong Xiao, Zhangxiu Lu, Zhipeng Li and Yiqun Li*
A novel palladium(II) carboxymethylcellulose (CMC-PdII) was prepared by direct metathesis from sodium carboxymethylcellulose
and PdCl2 in aqueous solution. Its catalytic activities were explored for Heck–Matsuda reactions of aryldiazonium tetrafluorobo-
rate with olefins, and Suzuki–Miyaura couplings of aryldiazonium tetrafluoroborate with arylboronic acid. Both reactions
proceeded at room temperature in water or aqueous ethanol media without the presence of any ligand or base, to provide the
corresponding cross-coupling products in good to excellent yields under atmospheric conditions. The CMC-PdII and
carboxymethylcellulose-supported palladium nanoparticles (CMC-Pd0) formed in situ in the reactions were characterized using
Fourier transform infrared spectroscopy, X-ray diffraction, inductively coupled plasma atomic emission spectrometry, and scan-
ning and transmission electron microscopies. The homogeneous nature of the CMC-Pd0 catalyst was confirmed via Hg(0) and
CS2 poisoning tests. Moreover, the CMC-Pd0 catalyst could be conveniently recovered by simple filtration and reused for at least
ten cycles in Suzuki–Miyaura reactions without apparently losing its catalytic activity. The catalytic system not only overcomes the
basic drawbacks of homogeneous catalyst recovery and reuse but also avoids the need to fabricate palladium nanoparticles in
advance. Copyright © 2015 John Wiley & Sons, Ltd.
Additional supporting information may be found in the online version of this article at the publisher’s web-site.
Keywords: carboxymethylcellulose; palladium nanoparticles; catalyst; Heck–Matsuda reaction; Suzuki–Miyaura reaction
Pd2(dba)3,[8] Pd(OAc)2,[9] PdCl2(CH3CN)2,[10] Pd(TFA)2/chiral
Introduction
bisoxazoline ligand,[11] palladacycle,[12] Pd–NHC complex,[13] Pd–
Palladium-catalyzed C(sp2)–C(sp2) coupling is a versatile and
important organic transformation process in both academic
laboratory and industrial fields. Among the great number of
palladium-catalyzed reactions, the well-known MizorokiÀHeck
and Suzuki–Miyaura reactions,[1] recognized with the 2010 Noble
Prize in Chemistry,[2] can be regarded as some of the most
important protocols for the construction of carbon–carbon bonds
by coupling of aryl halides with alkenes or boronic acids.[2,3] After
the pioneering explorations of Matsuda and co-workers who
adopted aryldiazonium salts as highly reactive alternatives for aryl
halides in the palladium-catalyzed Heck reaction, this variant of
the Heck–Mizoroki reaction is now named the Heck–Matsuda
reaction.[4] Aryldiazonium salts show greater reactivity than aryl ha-
lides and tolerance to various reaction conditions in the palladium-
mediated couplings, which make them potential substitutes for aryl
halides and allow the reaction to proceed smoothly under mild
conditions.[5] Recently, the progress of Heck–Matsuda[5,6] and/or
Suzuki–Miyaura[5,7] reactions using aryldiazonium salts in the for-
mation of carbon–carbon bonds has been reviewed. The traditional
procedure for a Heck–Matsuda reaction generally involves catalysis
using homogeneous palladium complexes including Pd(dba)2,4b)
phosphinous acid complexes,[14] and so on. Pioneering studies of
the Suzuki–Miyaura coupling of aryldiazonium salts with boronic
acids were reported in 1996 by Genêt and co-workers using
Pd(OAc)2 as catalyst.[15] The most frequently adopted homoge-
neous palladium catalysts involve Pd(OAc)2,[15,16] Na2PdCl4,[17]
PdCl2(CH3CN)2,[10] Pd(OAc)2/imidazolium carbene,[18] Pd(OAc)2/
thiourea ligand,[19] etc.
Although homogeneous palladium catalysts often have greater
activities in such kinds of carbon–carbon transformations due to
their excellent solubility in reaction media to form a homogenous
phase making all catalytic species accessible to the substrate, unfor-
tunately most homogeneous palladium catalysts are expensive, not
easily available, require air- and moisture-free handling and require
cumbersome separation of the catalyst from the reaction mixture
after the completion of the reaction. Moreover, the homogeneous
*
Correspondence to: Yiqun Li, Department of Chemistry, Jinan University,
Guangzhou 510632, China. E-mail: tlyq@jnu.edu.cn
Department of Chemistry, Jinan University, Guangzhou 510632, China
Appl. Organometal. Chem. 2015, 29, 646–652
Copyright © 2015 John Wiley & Sons, Ltd.

Heck–Matsuda and Suzuki–Miyaura reactions catalyzed by CMC-Pd0
palladium catalysts tend to form palladium black (bulk palladium)
by aggregation and precipitation causing them to lose their cata-
lytic activity.[20] To overcome these drawbacks, palladium catalysts
loaded on supports have drawn much attention and are widely
used in academic and industrial processes because of their ease
of work-up and the ease of separation of products and catalysts.
Among the variety of supported palladium catalysts, palladium
nanoparticle (Pd NP) catalysts have attracted considerable interest
because the carriers can efficiently control the growth of Pd NPs,
and further prevent their agglomeration, as well as merging the
merits of both homogeneous and heterogeneous catalytic
systems.[21] In spite of the significant developments in the area of
homogeneous catalysts for Heck–Matsuda and Suzuki–Miyaura
couplings, to date there are a limited number of supported
palladium complexes, and particularly Pd NP catalysts have been
explored. These include Pd(0)/C,[22] Pd(0)/BaCO3,[23] Pd NPs
immobilized on charcoal,[24] agarose-supported Pd NPs[25] and
ZnFe2O4-supported Pd NPs.[26] Considering the importance of the
construction of carbon–carbon bonds, more convenient and practi-
cal methodologies are still demanded.
It is well known that inexpensive and widely used cellulose and
its derivatives can have functional groups easily introduced by
chemical modification, which makes them suitable polymeric sup-
ports for heterogeneous catalysts. Sodium carboxymethylcellulose
(CMC-Na) is the major commercial common water-soluble cellulose
ether derivative which is widely used in pharmaceuticals, cosmetics
and foods. CMC-Na, containing carboxymethyl moieties (–CH2–
COOÀNa+), is capable of exchanging with metal cations. Based on
this property, we reported the preparation of palladium(II) carboxy-
methylcellulose (CMC-PdII) via direct utilization of PdCl2-exchanged
CMC-Na in aqueous solution and its application in carbon–carbon
couplings.[27] High catalytic activities are demonstrated of
carboxymethylcellulose-supported Pd NPs (CMC-Pd0) formed in situ
from CMC-PdII for both Suzuki–Miyaura and Mizoroki–Heck cross-
coupling reactions in the presence of low palladium loading.
Inspired by this result, herein we report the preparation and char-
acterization of CMC-PdII and, further, report its use as a recyclable
heterogeneous pre-catalyst for Heck–Matsuda and Suzuki–Miyaura
coupling reactions using various aryldiazonium salts in aqueous sol-
vent in air. To the best of our knowledge, to date, there has been no
report of employing the CMC-PdII catalyst precursor in such kinds of
cross-coupling reactions.
Table 1. Effect of amount of catalyst on Heck cross-coupling in watera
Entry
Amount of catalyst (mol% of Pd)
Time (h)
Yield (%)b
1
2
3
4
5
6
1
2
3
4
5
6
9
9
6
6
6
6
57
65
71
86
87
86
aReaction conditions: aryldiazonium tetrafluoroborate (1.5 mmol), acrylic
acid (1.0 mmol), catalytic amount of CMC-PdII, H2O (5 ml) at room
temperature.
bIsolated yields.
accordingly increase the reaction yield (Table 1, entries 4–6). There-
fore, 4 mol% of Pd is enough to push the reaction forward to
completion (Table 1, entry 4).
Next, the scope of substrates for the Heck–Matsuda reaction was
extended to various aryldiazonium salts bearing electron-donating
and/or electron-withdrawing groups at the aromatic cycle. It is evi-
dent from Table 2 that the couplings can be efficiently carried out at
room temperature in water to afford the (E)-products in excellent
yields ranging from 75 to 92%, and the (Z)-byproducts are not
found. In all cases examined, aryldiazonium salts bearing either
electron-donating or electron-withdrawing substituents exhibit a
similar effect on the yields (Table 2, entries 3–10). When the substit-
uent is at the ortho position of the aromatic ring, the yield of prod-
uct is lower than that when the same group is at the para position
owing to the greater steric hindrance (Table 2, entries 11–14).
Table 2. Reaction of various aryldiazonium tetrafluoroborate salts with
ethyl acrylate and acrylic acid in the presence of catalyst in watera
Entry
R1
4-H
R2
Time (h)
Yield (%)b
1
COOEt
COOH
COOEt
COOH
COOEt
COOH
COOEt
COOH
COOEt
COOH
COOEt
COOH
COOEt
COOH
8
6
8
6
8
6
8
8
9
8
8
8
8
8
78
86
76
88
81
90
81
92
82
91
72
81
69
75
Results and discussion
2
4-H
3
4-NO2
4-NO2
4-OCH3
4-OCH3
4-F
Initially, we investigated the coupling reaction of benzyldiazonium
tetrafluoroborate salts and acrylic acid in the presence of 1 mol%
of Pd in CMC-PdII in water at room temperature for 9 h. It is
observed that the reaction proceeds smoothly and produces the
desired product in 57% yield. No target product is detected in
the absence of the catalyst, which indicates that the catalyst plays
an essential role in the reaction. With these encouraging initial
results in hand, we further explored the effect of the amount of
catalyst on the model reaction of benzyldiazonium tetrafluorobo-
rate salts and acrylic acid. The results listed in Table 1 show that
the loading amount of catalyst has a significant effect on the
reaction. When 1 mol% of Pd is employed, the yield of product
reaches 57%. With increasing the amount of Pd from 1 to 4 mol%,
the reaction yield increases from 57 to 86% (Table 1, entries 1–4).
Further increasing the dose of Pd from 4 to 6 mol% does not
4
5
6
7
8
4-F
9
4-CH3
4-CH3
2-NO2
2-NO2
2-CH3
2-CH3
10
11
12
13
14
aReaction conditions: aryldiazonium tetrafluoroborate (1.5 mmol), olefin
(1.0 mmol), CMC-PdII (4 mol% of Pd), H2O (5 ml) at room temperature.
bIsolated yields.
Appl. Organometal. Chem. 2015, 29, 646–652
Copyright © 2015 John Wiley & Sons, Ltd.
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J. Xiao et al.
Table 3. Effect of solvent on Suzuki–Miyaura reactiona
Entry
Solvent
Amount of catalyst (mol% of Pd)
Time (h)
Yield (%)b
1
80% EtOH (v/v)
80% EtOH (v/v)
80% EtOH (v/v)
80% EtOH (v/v)
80% EtOH (v/v)
50% EtOH (v/v)
EtOH
1
2
3
4
5
3
3
3
3
3
3
3
3
3
3
3
1
1
1
1
1
3
64
76
88
88
89
70
76
78
70
73
57
2
3
4
5
6
7
8
80% MeOH (v/v)
50% MeOH (v/v)
MeOH
9
10
11
H2O
aReaction conditions: aryldiazonium tetrafluoroborate (1.5 mmol), phenylboronic acid (1.0 mmol), CMC-PdII (3 mol%), solvent (5 ml) at room temperature.
bIsolated yields.
Table 4. Suzuki–Miyaura coupling reactions of aryldiazonium tetrafluoroborate with phenylboronic acida
Entry
R1
R2
Time (h)
Yield (%)b
m.p. (°C)
1
2
3
4
5
6
7
8
9
OCH3
H
H
H
H
H
H
3
5
3
3
3
3
3
3
3
88
84
91
90
80
91
90
91
87
86–87
69–70
NO2
F
113–114
72–73
CH3
46–47
OCH3
OCH3
OCH3
OCH3
OCH3
F
179–181
88–89
NO2
CH3
105–106
107–109
aReaction conditions: aryldiazonium tetrafluoroborate (1.5 mmol), phenylboronic acid (1.0 mmol), CMC-PdII (3 mol%), 80% EtOH (v/v, 5 ml) at room
temperature.
bIsolated yields.
Table 5. Recycling of catalyst in Suzuki–Miyaura reactiona
Cycle
Time (min)
Yield (%)b
ICP analysis (mmol gÀ1 of Pd)
1
2
3
4
5
6
7
8
9
10
15
15
20
20
30
30
30
45
45
45
88
88
87
87
85
84
85
82
82
82
3.83
3.80
3.81
3.79
3.75
3.61
aReaction conditions: aryldiazonium tetrafluoroborate (1.5 mmol), phenylboronic acid (1.0 mmol), CMC-PdII (3 mol%), 80%EtOH (v/v, 5.0 ml) at room
temperature.
bIsolated yields.
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Heck–Matsuda and Suzuki–Miyaura reactions catalyzed by CMC-Pd0
Having found that CMC-PdII is an efficient catalyst for the Heck–
Matsuda reaction, its activity was also investigated in the Suzuki–
Miyaura reaction of 4-methoxybenzyldiazonium tetrafluoroborate
and phenylboronic acid as model reaction under the optimal condi-
tions obtained for the Heck–Matsuda reaction mentioned above.
Unfortunately, the product yield is moderate (Table 3, entry 11). In
order to find the optimal reaction conditions, the model reaction
was conducted at room temperature using a series of solvents in-
cluding EtOH, 80% EtOH (v/v), 50% EtOH (v/v), MeOH, 80% MeOH
(v/v) and 50% MeOH (v/v). Furthermore, the effect of the amount
of catalyst on the Suzuki–Miyaura coupling was also carefully
screened. The optimal conditions are summarized in Table 3.
As evident from Table 3, the reaction medium has an obvious ef-
fect on the coupling. Among the screened solvents, 80% EtOH (v/v)
is found to be the most suitable solvent for this reaction (Table 3,
entries 1–5). The results in Table 3 also reveal that a moderate yield
(64%) is obtained even if the palladium loading is as low as 1 mol%
(Table 3, entry 1). Satisfactory yield (88%) is achieved in 3 h in the
presence of 3 mol% Pd (Table 3, entry 3). Further increasing the
amount of Pd from 4 to 5 mol% does not obviously elevate the
product yields (Table 3, entries 4 and 5).
are listed in Table 4. The results clearly indicate that the CMC-PdII
catalyst is an efficient precatalyst for Suzuki–Miyaura coupling reac-
tions. All reactions of aryldiazonium tetrafluoroborate with
arylboronic acid proceed smoothly to afford the coupling products
with excellent yields (Table 4, entries 1–9). Both electron-rich and
electron-deficient substrates have no apparent influence on the
reactions.
For the aim of practical applications of a supported catalyst, the
recyclability of the catalyst is one of the most important factors.
To clarify this issue, catalytic recycling experiments were conducted
using the Suzuki–Miyaura reaction of 4-methoxybenzyldiazonium
Under the optimized reaction conditions, aryldiazonium tetraflu-
oroborate salts bearing both electron-donating and electron-
withdrawing substituents react with arylboronic acids correspond-
ingly, affording the desired products in excellent yields. The results
C
3465
3427
1696
1460
1114
1128
B
620
1443
1622
Figure 3. SEM images of (a) fresh CMC-PdII and (b) used CMC-Pd0 after
six runs.
A
1424
1637
1114
618
3458
3500
d
i
30
25
20
15
10
5
4000
3000
2500
2000
1500
1000
500
a
Wavenumber (cm-1)
s
t
r
i
Figure 1. FT-IR spectra of (A) CMC-Na, (B) CMC-PdII and (C) CMC-Pd0.
/
% b
u
t
i
0
o
n
30 50 70 90 120 200
(111)
d/nm
(200)
(220)
d
C
B
30
25
20
15
10
5
i
b
s
t
r
i
% b
u
t
i
o
n
/
0
A
d/nm
10
20
30
40
50
60
70
80
Figure 4. Particle size distribution histograms and TEM images of CMC-Pd0
(a) after the first run (scale bar, 500 nm) and (b) after the fifth run (scale bar,
200 nm).
2-Theta(deg)
Figure 2. XRD patterns of (A) CMC-Na, (B) CMC-PdII and (C) CMC-Pd0.
Appl. Organometal. Chem. 2015, 29, 646–652
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J. Xiao et al.
Table 6. CS2 poisoning testa
CS2/Pd (mol/mol)
Yield (%)b
0.1
86
0.5
87
1.0
84
1.5
83
2.0
83
CS2/Pd (mol/mol)
Yield (%)b
0.1
88
0.5
88
1.0
86
1.5
84
2.0
84
aCS2 was added to the mixture of both model reactions under optimal conditions.
bIsolated yields.
tetrafluoroborate and phenylboronic acid as a model. After the
completion of reaction, the catalyst was conveniently recovered
from the reaction mixture by simple filtration after the product
was extracted, washed thoroughly with 95% ethanol and diethyl
ether, and then dried in air. It can then be subjected to the next
run without further treatment. The results in Table 5 indicate that
the catalyst can be reused for ten runs without loss of its catalytic
activity. It is also found that only a trace amount of palladium metal
is leached out from the catalyst surface after each run. However, the
results from the recycling experiments reveal that leaching of trace
amounts of palladium has little influence on the reactivity.
It should be pointed out here that the initially brown CMC-PdII
catalyst turns dark after the first run, also implying the formation
of Pd NPs during the catalytic process. In order to confirm the
generation of Pd NPs in the Heck–Matsuda and Suzuki–Miyaura
reactions, freshly prepared CMC-PdII and used CMC-Pd0 catalyst
were characterized using Fourier transform infrared (FT-IR)
spectroscopy, X-ray diffraction (XRD), transmission electron mi-
croscopy (TEM) and scanning electron microscopy (SEM). The
homogeneous/heterogeneous nature of the CMC-Pd0 catalyst
was determined using CS2 and Hg(0) poisoning tests.
soluble active Pd(0) species or soluble Pd(0) clusters are leached
from the support and later re-precipitated onto the CMC at the
end of the catalytic cycle as already observed by our[28] and other
groups.[29b]
Various poisons that can selectively hinder the catalytic activity
of homogeneous versus heterogeneous catalysts can be used to
determine the nature of catalysts.[29] CS2 and Hg poisonings are
most popularly employed in metal-catalyzed reactions. CS2 binds
strongly to metal centers and inhibits the access of the substrate
to the active site of the catalyst. If less than 1.0 equiv. of added
CS2 (per metal atom) is able to poison the catalyst, it is considered
as a heterogeneous catalyst, which usually only has a fraction of
the metal atoms available for catalysis. On the contrary, more than
1.0 equiv. of added CS2 is usually required for a homogeneous
catalyst. For this reason, we performed a series of CS2 poisoning
experiments for both Heck–Matsuda reaction of phenyldiazonium
tetrafluoroborate with acrylic acid and Suzuki–Miyaura reaction of
4-methoxybenzyldiazonium tetrafluoroborate and phenylboronic
acid as model reactions at room temperature. The results are
listed in Table 6. It can be seen from the results in Table 6 that
the catalytic activity does not apparently decrease on increasing
the amount of CS2 from 0.1 to 2.0 equiv. of total Pd by compari-
son with the control reaction. These results demonstrate that
the catalysis is homogeneous in nature and soluble Pd(0) species
or soluble Pd(0) clusters are the true active species.
The main strength of Hg(0) in poisoning palladium metal is by
the formation of amalgams. The poison test was simply conducted
by carrying out the two model reactions mentioned above. It is
found that on addition of a large excess of 100 equiv. of Hg(0)
(per total Pd) to the reaction mixture, the yield of products of
Heck–Matsuda and Suzuki–Miyaura reactions remains at 25 and
28%, respectively, which suggests that the catalyst is homogeneous
in nature owing to the fact that Hg(0) does not suppress the
catalysis.
The FT-IR spectrum of CMC-Na shows a characteristic absorption
peak at 1114 cmÀ1 assigned to ether bond stretching. The peaks at
1637 and 1424 cmÀ1 are attributed to carboxylate (–COOÀ) sym-
metric and asymmetric stretching vibrations. The symmetric car-
boxylate absorption peak is negatively shifted to 1622 cmÀ1 in
the spectrum of CMC-PdII and positively shifted to 1696 cmÀ1 in
the spectrum of CMC-Pd0, indicating coordination of –COOÀ with
Pd(II) and Pd(0), respectively (Fig. 1).
The powder XRD diffraction patterns of CMC-Na, CMC-PdII and
CMC-Pd0 are shown in Fig. 2. By comparing their XRD patterns,
three weak peaks at 2θ of around 42°, 47° and 68° are clearly ob-
served for CMC-Pd0. These peaks are assigned to the diffraction of
the {111}, {200} and {220} lattice planes of palladium crystalline
structure, respectively.
The morphology of CMC-PdII and CMC-Pd0 was studied using
SEM and TEM. Clear differences in the morphology of CMC-PdII
and CMC-Pd0 are observed (Fig. 3). The particle size distributions
of the CMC-Pd0 catalyst were characterized using TEM, and repre-
sentative images are shown in Fig. 4. The TEM image of CMC-Pd0
after the first run shows that the mean size of Pd NPs is in the
region of 72.9 nm (Fig. 4(a)). The TEM image in Fig. 4(b) shows
the morphology and size of the catalyst after five runs, with better
uniform dispersion and an average size of 70.5nm. This observa-
tion supports a homogeneous mechanism where catalytically
Conclusions
The CMC-Pd0-catalyzed arylation reported here of aryldiazonium
salts with olefins and arylboronic acids has been developed
without the need of any ligand or base under mild reaction
conditions. The effectiveness of CMC-Pd0 in the reactions of vari-
ous aryldiazonium salts could be attributed to the highly soluble
active Pd(0) species or soluble Pd(0) clusters leached from Pd
NPs loaded on the CMC support formed in situ during the catalytic
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Appl. Organometal. Chem. 2015, 29, 646–652

Heck–Matsuda and Suzuki–Miyaura reactions catalyzed by CMC-Pd0
process. The mild reaction conditions combined with the widely
available substrates enable this transformation to be an attractive
alternative to the existing Heck–Matsuda and Suzuki–Miyaura
cross-couplings. The CMC-Pd0 catalyst can be regarded as an envi-
ronmentally benign catalyst, which is derived from the advan-
tages of cellulosic derivatives and the high catalytic activity of
metal nanoparticles, as well as reusability.
Poisoning tests of CMC-Pd0
Separate CS2 and Hg(0) poisoning experiments were conducted
using both Heck–Matsuda and Suzuki–Miyaura model reactions.
Various amounts of freshly prepared CS2 or a large excess of
Hg(0) as poison were added to the reaction mixture under our
optimal conditions. The work-up was the same as described
above.
Acknowledgments
Experimental
We are grateful to the National Natural Science Foundation of China
(nos. 21372099 and 21072077) and the Guangdong Natural Science
Foundation (nos. 10151063201000051 and 8151063201000016) for
financial support.
General
Melting points were measured with an Electrothermal X6
microscopic digital melting point apparatus. FT-IR spectra were
recorded with a Bruker Equinox-55 spectrometer using KBr pellets
in the range 400–4000 cmÀ1 1H NMR spectra were obtained
.
with a 500MHz Bruker Avance instrument with CDCl3 and References
DMSO-d6 as solvent and tetramethylsilane as internal standard.
[1] a) T. Mizoroki, K. Mori, A. Ozaki, Bull. Chem. Soc. Jpn. 1971, 44, 581; b)
The elemental palladium content of polymeric catalysts was
measured using inductively coupled plasma atomic emission
spectrometry (ICP-AES) with a PerkinElmer Optima 2000DV.
SEM was performed with a Philips XL 30ESEM instrument. TEM
was performed with a Philips Tecnai instrument operating at
40–100 kV. XRD patterns were obtained with an MSALXRD2 dif-
fractometer using Cu Kα radiation.
R. F. Heck, J. P. Nolley Jr., J. Org. Chem. 1972, 37, 2320; c) F. R. Heck,
Acc. Chem. Res. 1979, 12, 146.
[2] a) C. C. C. J. Seechurn, M. O. Kitching, T. J. Colacot, V. Snieckus, Angew.
Chem. Int. Ed. 2012, 51, 5062; b) X.-F. Wu, P. Anbarasan, H. Neumann,
M. Beller, Angew. Chem. Int. Ed. 2010, 49, 9047.
[3] a) F. Alonso, I. P. Beletskaya, M. Yus, Tetrahedron 2005, 61, 11771; b)
I. P. Beletskaya, A. V. Cheprakov, Chem. Rev. 2000, 100, 3009.
[4] a) K. Kikukawa, T. Matsuda, Chem. Lett. 1977, 159; b) K. Kikukawa,
K. Nagira, N. Terao, F. Wada, T. Matsuda, Bull. Chem. Soc. Jpn. 1979,
52, 2609; c) K. Kikukawa, K. Nagira, F. Wada, T. Matsuda, Tetrahedron
1981, 37, 31.
[5] a) A. Roglans, A. Pla-Quintana, M. Moreno-Mañas, Chem. Rev. 2006, 106,
4622; b) N. Oger, M. d’Halluin, E. Le Grognec, F.-X. Felpin, Org. Process
Res. Dev. 2014, 18, 1786.
CMC-PdII was prepared according to the literature.[27] The Pd
loading was found to be 3.83 mmol gÀ1 using ICP-AES. All
chemicals were obtained from commercial sources and were used
as received.
[6] a) J. G. Taylor, A. V. Moro, C. R. D. Correia, Eur. J. Org. Chem. 2011, 1403;
b) F.-X. Felpin, L. Nassar-Hardy, F. Le Callonnec, E. Fouquet, Tetrahedron
2011, 67, 2815.
General experimental procedure for Heck–Matsuda coupling
[7] H. Bonin, E. Fouquet, F.-X. Felpin, Adv. Synth. Catal. 2011, 353, 3063.
[8] a) A. V. Moro, F. S. P. Cardoso, C. R. D. Correia, Tetrahedron Lett. 2008, 49,
5668; b) C. Soldi, A. V. Moro, M. G. Pizzolatti, C. R. D. Correia, Eur. J. Org.
Chem. 2012, 3607; c) P. Prediger, L. F. Barbosa, Y. Génisson,
C. R. D. Correia, J. Org. Chem. 2011, 76, 7737.
[9] a) R. G. Kalkhambkar, K. K. Laali, Tetrahedron Lett. 2011, 52, 1733; b)
J. G. Taylor, R. da Silva Ribeiro, C. R. D. Correia, Tetrahedron Lett. 2011,
52, 3861; c) M. Raduán, J. Padrosa, A. Pla-Quintana, T. Parella,
A. Roglans, Adv. Synth. Catal. 2011, 353, 2003; d) N. Oger,
F. Le Callonnec, D. Jacquemin, E. Fouquet, E. Le Grognec, F.-X. Felpin,
Adv. Synth. Catal. 2014, 356, 1065; e) K. V. Kutonova, M. E. Trusova,
A. V. Stankevich, P. S. Postnikov, V. D. Filimonov, Beilstein J. Org. Chem.
2015, 11, 358.
A mixture of aryldiazonium tetrafluoroborate (1.5 mmol), olefin
(1.0 mmol) and a catalytic amount of CMC-PdII (4mol% Pd) was
stirred in water (5ml) at room temperature. The process was
monitored using TLC. The catalyst was separated by filtration after
the completion of the reaction and the filtrate was extracted with
diethyl ether (3× 5 ml). The combined organic phase was washed
with brine and dried over anhydrous MgSO4. The product was
obtained after removal of the ether solution using a rotary
evaporator. The desired pure products were further purified by
recrystallization. All the products are known, and 1H NMR data
were found to be identical to those reported in the literature.
[10] O. El Bakouri, M. Fernández, S. Brun, A. Pla-Quintana, A. Roglans,
Tetrahedron 2013, 69, 9761.
[11] a) C. C. Oliveira, R. A. Angnes, C. R. D. Correia, J. Org. Chem. 2013, 78,
4373; b) C. R. D. Correia, C. C. Oliveira, A. G. Salles Jr., E. A. F. Santos,
Tetrahedron Lett. 2012, 53, 3325.
General experimental procedure for Suzuki–Miyaura coupling
[12] a) J. Salabert, R. M. Sebastían, A. Vallribera, J. F. Cívicos, C. Nájera,
Tetrahedron 2013, 69, 2655; b) J. Salabert, R. M. Sebastían,
A. Vallribera, A. Roglans, C. Nájera, Tetrahedron 2011, 67, 8659.
[13] a) I. Peñafiel, I. M. Pastor, M. Yus, Eur. J. Org. Chem. 2012, 3151; b)
M. B. Andrus, C. Song, J. Zhang, Org. Lett. 2002, 4, 2079.
[14] K. Canto, R. da Silva Ribeiro, A. F. P. Biajoli, C. R. D. Correia, Eur. J. Org.
Chem. 2013, 8004.
[15] a) S. Darses, T. Jeffery, J.-L. Brayer, J.-P. Demoute, J.-P. Genêt, Bull. Soc.
Chim. Fr. 1996, 133, 1095; b) S. Darses, T. Jeffery, J.-P. Genêt,
J.-L. Brayer, J.-P. Demoute, Tetrahedron Lett. 1996, 37, 3857.
[16] a) J. T. Kuethe, K. G. Childers, Adv. Synth. Catal. 2008, 350, 1577; b)
F. Le Callonnec, E. Fouquet, F.-X. Felpin, Org. Lett. 2011, 13, 2646.
[17] D. M. Willis, R. M. Strongin, Tetrahedron Lett. 2000, 41, 6271.
[18] M. B. Andrus, C. Song, Org. Lett. 2001, 3, 3761.
In a typical experiment, the CMC-PdII catalyst (3 mol% of Pd) was
added into
a mixture of aryldiazonium tetrafluoroborate
(1.5 mmol) and arylboronic acid (1.0mmol) in 80% EtOH (5ml),
and the reaction mixture was stirred at room temperature. Upon
the completion of the reaction, the catalyst was removed by
filtration, washed adequately with 95% ethanol and diethyl
ether, and dried in air for the next run. The filtrate was extracted
with diethyl ether (3× 5 ml). The organic fractions were then
concentrated using a rotary evaporator to afford the desired
biaryl. The crude products were further purified by recrystalliza-
tion in excellent yield. All of the products are known com-
pounds, and their 1H NMR data were identical to those
reported in the literature.
[19] M. J. Dai, B. Liang, C. Wang, Z. You, J. Xiang, G. Dong, J. Chen, Z. Yang,
Adv. Synth. Catal. 2004, 346, 1669.
[20] D. Astruc, Inorg. Chem. 2007, 46, 1884.
Appl. Organometal. Chem. 2015, 29, 646–652
Copyright © 2015 John Wiley & Sons, Ltd.
wileyonlinelibrary.com/journal/aoc

J. Xiao et al.
[21] I. Beletskaya, V. Tyurin, Molecules 2010, 15, 4792.
[29] a) J. A. Widegren, R. G. Finke, J. Mol. Catal. A 2003, 198, 317; b)
N. T. S. Phan, M. Van Der Sluys, C. W. Jones, Adv. Synth. Catal. 2006,
348, 609.
[22] a) R. H. Taylor, F.-X. Felpin, Org. Lett. 2007, 9, 2911; b) A. P. Colleville,
R. A. J. Horan, N. C. O. Tomkinson, Org. Process Res. Dev. 2014, 18, 1128.
[23] F.-X. Felpin, E. Fouquet, Adv. Synth. Catal. 2009, 350, 863.
[24] a) F.-X. Felpin, E. Fouquet, C. Zakri, Adv. Synth. Catal. 2008, 350, 2559; b)
F.-X. Felpin, E. Fouquet, C. Zakri, Adv. Synth. Catal. 2009, 351, 649.
[25] M. Gholinejad, Appl. Organometal. Chem. 2013, 27, 19.
[26] A. S. Singh, S. S. Shendage, J. M. Nagarkar, Tetrahedron Lett. 2013, 54,
6319.
Supporting information
Additional supporting information may be found in the online ver-
sion of this article at the publisher’s web-site.
[27] J. Xiao, Z. Lu, Y. Li, Ind. Eng. Chem. Res. 2015, 54, 790.
[28] F. Chen, M. Huang, Y. Li, Ind. Eng. Chem. Res. 2014, 53, 8339.
wileyonlinelibrary.com/journal/aoc
Copyright © 2015 John Wiley & Sons, Ltd.
Appl. Organometal. Chem. 2015, 29, 646–652