Pd immobilized on polyamide based on melamine and terephalic acid as an efficient and recyclable catalyst for Suzuki-Miyaura coupling reaction

Article abstract of DOI:10.1002/aoc.4135

A simple synthetic strategy of polyamide was described from melamine and terephalic acid via one-step polycondensation. PdCl₂ was then immobilized on the polyamide (denoted as Pd/MPA). Melamine and terephalic acid not only acted as monomers but also provided the ligand sites to help the polyamide to coordinate with Pd(II). The Pd/MPA catalyst was characterized by FT-IR, TGA, SEM, TEM, XPS, N₂ adsorption-desorption and atomic absorption spectroscopy. The catalyst was used in Suzuki-Miyaura coupling reaction of various aryl halides, including less reactive chlorobenzene and benzyl chloride, to give the coupling products in moderate to excellent yields. High turnover frequencies (TOF) up to 29400 h^-1 can be also obtained. In addition, it behaved truly as a heterogeneous catalyst with high reusability after being recycled 6 times and palladium leaching was negligible during the process. This work provides a practical polyamide support to develop heterogeneous palladium catalysts with simple synthetic procedure and low cost.

Full text of DOI:10.1002/aoc.4135

Received: 19 July 2017
DOI: 10.1002/aoc.4135
Revised: 20 September 2017
Accepted: 23 September 2017
F U L L P A P E R
Pd immobilized on polyamide based on melamine and
terephalic acid as an efficient and recyclable catalyst for
Suzuki‐Miyaura coupling reaction
1
1
1
1
1,2
1
Jian Chen | Ju Zhang | Weiting Sun | Kunpeng Song | Dajian Zhu
| Tao Li
1
Hubei Key Laboratory of Material
A simple synthetic strategy of polyamide was described from melamine and
Chemistry and Service Failure, Key
Laboratory of Material Chemistry for
Energy Conversion and Storage, Ministry
of Education, School of Chemistry and
Chemical Engineering, Huazhong
University of Science and Technology,
Wuhan 430074, China
terephalic acid via one‐step polycondensation. PdCl was then immobilized
2
on the polyamide (denoted as Pd/MPA). Melamine and terephalic acid not only
acted as monomers but also provided the ligand sites to help the polyamide to
coordinate with Pd(II). The Pd/MPA catalyst was characterized by FT‐IR, TGA,
SEM, TEM, XPS, N2 adsorption‐desorption and atomic absorption
spectroscopy. The catalyst was used in Suzuki‐Miyaura coupling reaction of
various aryl halides, including less reactive chlorobenzene and benzyl chloride,
to give the coupling products in moderate to excellent yields. High turnover
2
Shenzhen Research Institute of
Huazhong University of Science and
Technology, 9 Yuexing Third Avenue,
Shenzhen 518057, China
‐
1
frequencies (TOF) up to 29400 h can be also obtained. In addition, it behaved
truly as a heterogeneous catalyst with high reusability after being recycled 6
times and palladium leaching was negligible during the process. This work
provides a practical polyamide support to develop heterogeneous palladium
catalysts with simple synthetic procedure and low cost.
Correspondence
Dajian Zhu and Tao Li, School of
Chemistry and Chemical Engineering,
Huazhong University of Science and
Technology, Wuhan 430074, China.
Email: zhudj@hust.edu.cn;
taoli@hust.edu.cn
KEYWORDS
Funding information
melamine, Pd catalyst, polyamide‐supported, Suzuki‐Miyaura reaction
Natural Science Foundation of Hubei
Province, Grant/Award Number:
2016CFB537; Shenzhen Science and
Technology Innovation Program, Grant/
Award Number: JCYJ20150630155150201;
National Natural Science Foundation of
China, Grant/Award Number: 21473064
1
| INTRODUCTION
heterogeneous catalytic systems seems to be more
favorable.
[
4]
The palladium‐catalyzed Suzuki‐Miyaura coupling reac-
tion offers an efficient strategy to form carbon‐carbon
Palladium immobilized on insoluble supports can be
easily separated from the reaction mixtures and recycled.
[1]
[5]
[6–10]
[11,12]
bonds, which was widely used in the synthesis of
biaryls or substituted aromatic moieties. Simple
palladium(II) salts or different soluble palladium
complexes were explored as potential homogeneous
Molecular sieves,
silicas,
metal oxides,
[
13–15]
[16–23]
carbons
and various polymers
have been used
as the supports. The ligand moleculars, which can
coordinate with Pd, tend to be grafted onto the supports.
Compared with the inorganic supports, organic polymer
supports show the advantage in their versatility in tuning
their composition and functionality for controllable
[2,3]
catalysts.
However, these homogeneous palladium
catalysts usually make their isolation problematical
and increase a risk of contamination of the reaction
products with this toxic metal. Therefore, the use of
[
4]
catalyst immobilization or encapsulation.
However,
Appl Organometal Chem. 2017;e4135.
wileyonlinelibrary.com/journal/aoc
Copyright © 2017 John Wiley & Sons, Ltd.
1 of 9
https://doi.org/10.1002/aoc.4135

2
of 9
CHEN ET AL.
[
17,22,23]
some monomers are very expensive
or some
2.2 | Measurements and characterizations
ligands need to be pre‐functionalized to the backbone of
[22,23]
FT‐IR spectra were recorded under ambient conditions in
the wave number range of 4000‐400 cm‐ using a Bruker
VERTEX 70 FT‐IR Spectrometer. XPS was performed in
a VG multilab 2000 spectrometer, using a Mg‐Al Ka
X‐ray source with the pass energy at 100 eV. The sample
was degassed in a chamber at 5 × 10‐ mbar at room
temperature. C 1s transition was adjusted at 284.6 eV.
SEM images were obtained on a FEI Sirion 200 scanning
electron microscope at 10 kV. TEM images were taken
on a Tecnai G20 microscope (FEI Corp. USA) instrument
operated at an accelerating voltage of 200 kV. TGA data
were recorded on a PerkinElmer Diamond TG/DTA
instrument, thermobalance at a heating rate of 10 °C
the polymers.
These may make the polymer synthe-
1
sis with high cost and complicated process, which will
limit practical application of polymer supports. From a
practical point of view, the low cost of polymer supports
and the simple synthetic procedure of related Pd hetero-
geneous catalysts with excellent performance are highly
desired.
The structure of melamine is similar to pyrimidine
ligand that has proven to be useful in Pd‐catalyzed cou-
Besides, melamine is also inexpensive
~$0.003 USD/mmol). Therefore, melamine may act as
monomer to synthesize the polymer with low cost and
provide ligand sites to coordinate with Pd. Recently,
Chalker used melamine and melamine‐formaldehyde
polymers as ligands for Pd‐catalyzed Suzuki‐Miyaura
However, the yield in second and third use
of this polymer‐supported Pd catalyst was typically about
10
[24]
pling reactions.
(
‐
1
min under nitrogen. Catalyst surface area, N adsorption
2
isotherm (77.3 K) and pore size distribution were mea-
sured using Micromeritics ASAP 2020M surface area and
porosity analyzer. Before analysis, the sample was
degassed at 200 °C for 8 h under vacuum (10‐ bar). Pd
content data were obtained on Perkin Elmer AA‐800
(USA). GC analyses were performed in a Fuli GC9790
(Wenling, China), equipped with a FFAP (30 m × 0.25
mm × 0.25 μm) capillary column and a flame ionization
detector (FID).
[25]
reaction.
5
3
0% lower than the yield in the first use.
We previously have reported Pd‐supported on
[
26–28]
triphenylphosphine‐based polymers,
N‐heterocyclic
porphyrin‐based
[29]
carbene‐based
polymer,
and
[
30]
polymer
in Suzuki‐Miyaura reaction. In this article,
we prepared a kind of polyamide via one‐step polycon-
[31]
densation
of melamine and terephalic acid which are
both inexpensive raw monomers. Then PdCl was sup-
ported on this polyamide and used in Suzuki‐Miyaura
2
2.3 | Synthesis of polyamide
reaction.
Melamine (1.40 g, 11.1 mmol) was added to a solution
of terephalic acid (2.49 g, 15.0 mmol) in 30 ml ethanol.
The mixed solution was stirred at 80 °C for 0.5 h and
then dried in a rotary evaporator (80 °C for 3 h) to
remove ethanol. The mixture of melamine and
terephalic acid was transferred into a crucible and cal-
cined in an oven at 200 °C for 20 h. The resulting white
powder was washed with ethanol in a Soxhlet for 168 h,
and finally dried under vacuum at 60 °C for 24 h. The
resulting polyamide material was denoted as MPA (see
Scheme 1).
2
2
| EXPERIMENTAL
.1 | Materials
Aryl bromides, aryl chlorides and benzyl chloride were
purchased from Alfa Aesar. Melamine, terephalic acid,
PdCl , bases and solvents were obtained from Sinopharm
2
Chemical Reagent Co., Ltd. of China. All chemicals were
of analytical grade and used without further purification.
SCHEME 1 Synthesis of Pd/MPA catalyst

CHEN ET AL.
3 of 9
2
.4 | Synthesis of Pd/MPA
with diamine. Terephthaloyl chloride is environmental
unfriendly and strong corrosive. In our work, we used
melamine and terephalic acid as the monomers. The syn-
thetic process was shown in Scheme 1. The polycondensa-
tion of melamine and terephalic acid was carried out in
Polyamide‐supported Pd catalyst was prepared by coordi-
nating palladium(II) ions with the polyamide. Briefly,
MPA (1.0 g) and PdCl (0.10 g) were added to acetonitrile
and hydrochloric acid mixed solution (20 mL acetonitrile
and 5 drops hydrochloric acid) and refluxed at 70 °C for
2
200 °C to remove water. This process is very simple, envi-
ronmental friendly and low cost.
1
2 h. The solid was filtered, washed repeatedly with
The polyamide was identified by FT‐IR measurements
anhydrous ethanol to remove physisorbed palladium(II)
species on the support. The final catalyst was dried at 60
(
see Figure 1). The absorption peak in MPA and Pd/MPA
‐1
at 3342 cm is due to the N‐H stretching vibration while
the peaks at 1676 and 1566 cm are due to the C = O
°C under vacuum and the as‐prepared catalyst was
‐1
denoted as Pd/MPA (see Scheme 1).
stretching vibration of amide and N‐H variable angular
[
33]
vibration respectively.
Compared with synthetic raw
material of melamine, the strong stretching vibration in
2
.5 | Suzuki‐Miyaura reaction catalyzed
‐1
melamine at 3422 and 3475 cm for N‐H stretching (pri-
by Pd/MPA
mary amine) were changed into one peak at 3342 cm‐
1
Suzuki‐Miyaura coupling reaction was carried out at 80
(
N‐H stretching, secondary amine). The spectra obtained
°C in a 10 ml reactor under N atmosphere. In a typical
2
for MPA and Pd/MPA clearly show the almost disappear-
run, Pd/MPA catalyst (10 mg), aryl halide (0.5 mmol),
phenylboronic acid (0.75 mmol) and base (1.5 mmol)
were added to solvent (2 ml) and allowed to react for
definite time. Quantitative analysis was performed on a
GC9790 using n‐dodecane as the internal standard.
ance of the characteristic N‐H stretching band of the free
‐1
amine group (3100‐3300 cm ), indicating the consump-
[34]
tion of the free amine group.
The FT‐IR results suggest
the success of the polycondensation between melamine
and terephalic acid.
XPS was employed to investigate the coordination
state of the Pd species. XPS spectra for Pd/MPA‐used
and fresh Pd/MPA catalyst were displayed in Figure 2. It
revealed that the Pd species in the fresh Pd/MPA catalyst
was mostly present in +2 oxidation state rather than in
metallic state. In comparison with the binding energies
of PdCl at 337.9 eV and 343.1 eV in the Pd 3d and Pd
2
.6 | Reusability test of the catalyst
In order to determine the catalyst durability, the Pd/MPA
catalyst was separated by centrifugation after each run of
reaction and the clear supernatant liquid was determined
by GC9790. After being washed with ethanol as well as
water, and dried under vacuum at 50 °C for 12 h, the cat-
alyst was re‐used with fresh charge of solvent and reac-
tants for subsequent reaction under the same conditions.
We performed another five runs after centrifugation.
2
5/2
[
35]
3d3/2, respectively,
the binding energies for the Pd(II)
species in the fresh catalyst were shifted to 337.6 eV and
3
42.8 eV. This negative shift can be attributed to the
[36]
strong electron‐donation of the polyamide support.
The XPS of Pd/MPA‐used after the sixth run showed
the presence of the related peaks for Pd(II) and Pd(0) (see
Figure 2). Two peaks detected at 335.2 eV (Pd 3d5/2) and
340.5 eV (Pd 3d3/2) are attributed to the Pd(0) species.
2
.7 | Hot filtration test
Hot filtration test was carried out to determine whether
the heterogeneous or the dissolved homogeneous Pd spe-
cies were the real catalyst responsible for the reaction.
The following strategy was adopted. Reaction between
chlorobenzene and phenylboronic acid was performed to
carry out hot filtration test. After 1 h, the reaction mixture
was filtered through a syringe filter (0.2 μm) and analyzed
by GC9790. Then, the filtrate was allowed to react for
another 9 h under the similar conditions.
3
3
| RESULTS AND DISCUSSION
.1 | Synthesis of Pd/MPA catalyst
The polyamides are generally synthesized from the mono-
[31]
[32]
mers of dicarboxylic acid
or terephthaloyl chloride
FIGURE 1 FT‐IR spectra for different samples

4
of 9
CHEN ET AL.
FIGURE 2 XPS of Pd/MPA‐used and fresh Pd/MPA catalyst
Pd 3d)
(
The other two peaks at 337.6 eV (Pd 3d5/2) and 342.8 eV
Pd 3d3/2) could be attributed to Pd(II) species that are
(
incorporated into the Pd/MPA‐used catalyst. There were
about 34.1% of Pd(0) species in the Pd/MPA‐used catalyst
from the integral area of XPS spectra. These results indi-
cated that Pd(0) nanoparticles were formed during the
Suzuki‐Miyaura coupling reaction, similarly as it was
[
37,38]
observed in other immobilized palladium catalysts.
Moreover, compared with the MPA, the binding energies
of N 1s and O 1s of Pd/MPA were both shifted to positive
direction (see Figure 3), which indicated the coordination
[39]
of Pd with N and O atoms of polyamide.
FIGURE 3 XPS of MPA and Pd/MPA catalyst (a: N1 s, b: O1s)
The morphologies of fresh and Pd/MPA‐used catalysts
were investigated by SEM. SEM images displayed the
nanosheet structure with several micrometers in size (see
Figure 4). The shape of the Pd/MPA catalyst maintained
well after the Suzuki‐Miyaura coupling reaction (see
Figure 4b). The layer structure of polyamide was also
observed through TEM (see Figure 5a). No Pd(0) nanopar-
ticles were observed in polyamide matrix from TEM
image of fresh Pd/MPA catalyst. This was consistent with
the XPS result of +2 Pd oxidation state in fresh catalyst.
However, Pd nanoparticles with the average diameter of
at high pressure (P/P < 0.95), which was suggestive of
0
the existence of mesopores in the frameworks. The BET
surface area, pore size and pore volume were summarized
2
in Table 1. The BET area was 193.6 m /g and the average
pore size was 5.4 nm. The results of N2 adsorption/
desorption isotherms measurement confirmed the
presence of such porous structure.
3
.2 | Suzuki‐Miyaura reaction catalyzed
3
.2 nm were clearly observed in the Pd/MPA‐used catalyst
see Figure 5b). These results were also in agreement with
XPS spectra.
The thermal stability of Pd/MPA was evaluated by
by Pd/MPA
(
The experiments with different solvents and bases were
performed to find the best condition for the coupling
reaction over Pd/MPA catalyst. The results were shown in
Table 2. Water was firstly chosen as solvent to screen the
bases (Table 2, entries 1‐10). K PO ·3H O was the best
TGA, and the thermogram was given in Figure 6. Accord-
ing to this curve, the weight loss below 250 °C was lower
than 3%. There was a dramatic decrease of weight loss
from 310 to 350 °C. So this result indicated that Pd/MPA
catalyst has high thermal stability below 250 °C.
N2 adsorption/desorption isotherms of Pd/MPA
catalyst were shown in Figure 7. It displayed typical type
І sorption isotherm curve along with a large adsorption
3
4
2
base for this reaction. The yield can reach 99% with 6 h
(Table 2, entry 1). Considerable yields can also be obtained
with ethylenediamine, NaHCO , KOH, K CO as the base
3
2
3
(Table 2, entries 4 and 7‐9). While low yields were
obtained with NH ·H O, NaOH, Na C O as the base
3
2
2 2 4

CHEN ET AL.
5 of 9
FIGURE 4 SEM images of Pd/MPA catalyst (a: fresh, b: used)
(Table 2, entries 2, 6 and 10). When ethanol was used as
solvent, the yields were poor (Table 2, entries 11 and 12).
K PO ·3H O was then used as base for optimizing solvents
FIGURE 5 TEM images of Pd/MPA catalyst (a: fresh, b: used)
3
4
2
(Table 2, entries 13‐17). The yield of 99% can be obtained
in toluene with 20 min (Table 2, entry 13). When the reac-
tion time was decreased to only 2 min, a high yield can also
be maintained about 92% (Table 2, entry 18) and the turn-
over frequency (TOF) and turnover number (TON) of the
reaction can reach to 29400 h‐ and 980, which may be
lower than the catalytic results of some Pd homogeneous
1
catalysts (TOF up to 55000 h‐ and TON up to 9000).
1
[40]
However the TOF was much higher than many Pd hetero-
geneous catalysts, such as polymer‐supported Pd (TOF up
‐
1 [41]
to 500 h ),
polystyrene‐supported Pd (TOF up to 2700
‐
1 [42]
h ) or inorganic material‐supported Pd (TOF up to
50‐1700 h ).
‐1 [43,44]
3
The comparison results showed the
excellent efficiency of Pd/MPA as a heterogeneous catalyst
in Suzuki‐Miyaura reaction.
FIGURE 6 TGA of Pd/MPA catalyst

6
of 9
CHEN ET AL.
The effect of different substrates on Suzuki‐Miyaura
reaction over Pd/MPA catalyst was shown in Table 3.
When bromobenzene was coupled with arylboronic acids
containing both electron‐donating and electron‐with-
drawing groups, the corresponding products were
obtained in excellent yields within 2 h (Table 3, entries
2‐5). Moreover, when phenylboronic acid was coupled
with different aryl bromides, the catalyst also gave
excellent yields (Table 3, entries 6‐7). To our delight,
the coupling reaction of inactive aryl chlorides with
phenylboronic acid extended reaction time to 10 h, also
giving the desired products in moderate to excellent yields
(Table 3, entries 8‐11). The coupling of benzyl chloride
and phenylboronic acid remains a challenge, especially
FIGURE 7
catalyst
2
N adsorption/desorption isotherms of Pd/MPA
[
26]
using heterogeneous catalysts.
The catalytic activity
TABLE 1 Pore parameters of Pd/MPA catalyst
towards the coupling of benzyl chloride and
phenylboronic acid was also examined. The Pd/MPA
catalyst gave diphenylmethane with moderate yield of
BET area
(m /g)
V
total
3
Average pore
size (nm)
2
a
b
Catalyst
(cm /g)
7
0% (Table 3, entry 12), even better than some homoge-
Pd/MPA
193.6
0.236
5.4
[
45–47]
neous catalysts (35‐48% yield),
that Pd/MPA has high activity for the coupling of benzyl
chloride and phenylboronic acid.
which demonstrates
a
2
2
Surface area (m /g) calculated from the N adsorption based on the BET
model.
b
3
0
The total pore volume (cm /g) calculated at P/P = 0.99.
a
TABLE 2 The effect of solvents and bases on Suzuki‐Miyaura reaction
b
Solvent
Base
PO
NH ·H
Et NH
Ethylenediamine
IO
Time (h)
Yield (%)
c
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
H
H
H
H
H
H
H
H
H
H
2
2
2
2
2
2
2
2
2
2
O
O
O
O
O
O
O
O
O
O
K
3
4
·3H
2
O
6
99
3
2
O
6
38
0
2
6
6
93
77
41
90
82
82
45
45
3
K
3
3
6
NaOH
NaHCO
KOH
6
3
6
6
K
2
CO
Na
Et
EtONa
3
6
0
1
2
3
4
5
6
7
8
2
C
2
O
4
6
EtOH
3
N
6
EtOH
6
c
Toluene
1,4‐Dioxane
DMF
K
K
K
K
K
K
3
3
3
3
3
3
PO
PO
PO
PO
PO
PO
4
4
4
4
4
4
·3H
·3H
·3H
·3H
·3H
·3H
2
2
2
2
2
2
O
O
O
O
O
O
20 min
20 min
20 min
20 min
20 min
2 min
99
65
24
86
87
92
MeOH
EtOH
Toluene
a
2
Reaction conditions: Pd/MPA (10 mg), 0.5 mmol bromobenzene, 0.75 mmol phenylboronic acid, 1 mmol base, 2 ml solvent, 80 °C, N atmosphere.
b
Yields were determined by GC using n‐dodecane as an internal standard.
c
Isolated yield.

CHEN ET AL.
7 of 9
a
TABLE 3 Effect of substrates on Suzuki‐Miyaura reaction over Pd/MPA catalyst
b
Substrate 1
Substrate 2
Time (h)
Yield (%)
1
2
20 min
99
2
99
3
4
5
6
7
8
9
2
98
92
95
97
97
99
99
2
2
2
2
10
10
1
0
10
77
1
1
1
2
10
10
56
70
a
Reaction conditions: Pd/MPA (10 mg), 0.5 mmol aryl halide, 0.75 mmol arylboronic acid, 1.5 mmol K
3
PO
4
·3H
2
O, 2 ml toluene, 80 °C, N
2
atmosphere.
b
Isolated yield.
3
.3 | Reusability of Pd/MPA catalyst and
Pd leaching during Suzuki‐Miyaura
reaction
From the industrial point of view, the reusability of the
catalyst is important for large scale operation. Therefore
the reusability of Pd/MPA catalyst was examined in the
coupling reaction of bromobenzene with phenylboranic
acid at 80 °C for 2 min in toluene. The results were
shown in Figure 8. The catalyst can be reused six times
to give biphenyl with excellent yields, which showed
[48]
better stability than silica‐supported Pd catalyst.
recovered catalyst was checked with SEM analysis
Figure 4b). The Pd/MPA catalyst showed no significant
change in morphology compared with the fresh catalyst,
The
(
FIGURE 8 Reusability of Pd/MPA catalyst for Suzuki‐Miyaura
reaction

8
of 9
CHEN ET AL.
which means the structure of the polyamide can be
maintained in the reuse.
In addition, to probe the Pd leaching of the catalyst,
hot filtration test was performed. The reaction between
chlorobenzene and phenylboronic acid was stopped after
ORCID
Dajian Zhu http://orcid.org/0000-0001-6500-0763
REFERENCES
1
h and the Pd/MPA catalyst filtered off while the solution
[
[
[
[
[
1] N. Miyaura, A. Suzuki, Chem. Rev. 1995, 95, 2457.
2] R. Martin, S. L. Buchwald, Acc. Chem. Res. 2008, 41, 1461.
3] N. Marion, S. P. Nolan, Acc. Chem. Res. 2008, 41, 1440.
4] P. Das, W. Linert, Coord. Chem. Rev. 2016, 311, 1.
was still hot. It showed a 25% conversion of chloroben-
zene. The filtrate was heated further and the reaction
mixture was analyzed after 10 h. To our delight, no
significant change in either the conversion or the yield
was observed, which indicated that the reaction stopped
after Pd/MPA catalyst was filtered off. The results of hot
filtration test revealed that the Pd leaching was negligible
and the reaction was really heterogeneous in nature.
Atomic absorption spectroscopy (AAS) also showed that
the sixth used Pd/MPA catalyst can be still maintained
5] A. Fodor, Z. Hell, L. Pirault‐Roy, Appl. Catal. A 2014, 484, 39.
[6] M. G. Speziali, A. G. M. da Silva, D. M. Vaz de Miranda, A. L.
Monteiro, P. A. Robles‐Dutenhefner, Appl. Catal. A 2013,
462‐463, 39.
[
[
7] S. Ungureanu, H. Deleuze, O. Babot, M.‐F. Achard, C. Sanchez,
M. I. Popa, R. Backov, Appl. Catal. A 2010, 390, 51.
8] A. Martinez, J. L. Krinsky, I. Penafiel, S. Castillon, K. Loponov,
0
.50(±0.01) wt% Pd nearly the same as the fresh catalyst.
A. Lapkin, C. Godard, C. Claver, Catal. Sci. Technol. 2015, 5,
The skeleton of MPA offered a robust scaffold for PdCl2
and the ligand sites incorporated into the polyamide
backbone, which effectively reduced the extent of Pd
leaching into the reaction solution after the catalytic
reaction. Compared with some inorganic supports, the
structure of MPA may be more helpful to stabilize Pd
310.
[9] F. Wei, C. Cao, Y. Sun, S. Yang, P. Huang, W. Song,
ChemCatChem 2015, 7, 2475.
[
10] B. W. Glasspoole, J. D. Webb, C. M. Crudden, J. Catal. 2009,
265, 148.
[48]
[11] H. Keypour, S. G. Saremi, M. Noroozi, H. Veisi, Appl.
Organometal. Chem. 2017, 31, 3558.
species.
[
[
[
[
[
[
[
12] A. R. Hajipour, N. S. Tadayoni, Z. Khorsandi, Appl.
Organometal. Chem. 2016, 30, 590.
4
| CONCLUSION
13] E. J. Garcia‐Suarez, P. Lara, A. B. Garcia, M. Ojeda, R. Luque,
K. Philippot, Appl. Catal. A 2013, 468, 59.
In summary, we report a simple synthesis of polyamide
from melamine and terephalic acid using one‐step
polycondensation. This polyamide‐supported Pd(II)
catalyst showed high catalytic activity and reusability in
Suzuki‐Miyaura reaction. It could be easily recovered
and a high yield was obtained even after the catalyst
was reused 6 times. High turnover frequencies (TOF) up
to 29400 h‐ can be obtained. The skeleton of MPA can
effectively reduce the extent of metal leaching into the
reaction. The cheap monomers and simple preparation
process make this polyamide as a practical support for
specific catalysis. We envision that these results will
provide inspiration for further design and synthesis of
polyamide‐based supports for the development of
large‐scale industrial catalysis.
14] S. N. Jadhav, A. S. Kumbhar, C. V. Rode, R. S. Salunkhe, Green
Chem. 2016, 18, 1898.
15] W. Dong, S. Cheng, C. Feng, N. Shang, S. Gao, C. Wang, Z.
Wang, Appl. Organometal. Chem. 2017, 31, 3741.
16] L. Geng, Y. Li, Z. Qi, H. Fan, Z. Zhou, R. Chen, Y. Wang, J.
Huang, Catal. Commun. 2016, 82, 24.
1
17] L. You, W. Zong, G. Xiong, F. Ding, S. Wang, B. Ren, I.
Dragutan, V. Dragutan, Y. Sun, Appl. Catal. A 2016, 511, 1.
18] Z. Dong, Z. Ye, Adv. Syn. Catal. 2014, 356, 3401.
[19] H. Choudhary, S. Nishimura, K. Ebitani, J. Mater. Chem. A
014, 2, 18687.
2
[20] C. Zhang, J.‐J. Wang, Y. Liu, H. Ma, X.‐L. Yang, H.‐B. Xu,
Chem. Eur. J. 2013, 19, 5004.
[21] K. Bester, A. Bukowska, W. Bukowski, Appl. Catal. A 2012,
443‐444, 181.
[
22] W. Xia, L. Huang, X. Huang, Y. Wang, C. Lu, G. Yang, Z. Chen,
ACKNOWLEDGEMENTS
J. Nie, J. Mol. Catal. A 2016, 412, 93.
This work was supported by the National Natural
Science Foundation of China (21473064), Shenzhen
[23] C.‐A. Wang, Y.‐F. Han, Y.‐W. Li, K. Nie, X.‐L. Cheng, J.‐P.
Zhang, RSC Adv. 2016, 6, 34866.
Science
and
Technology
Innovation
Program
[24] V. Böhrsch, C. P. R. Hackenberger, ChemCatChem 2010, 2, 243.
(JCYJ20150630155150201), Natural Science Foundation
[25] G. A. Edwards, M. A. Trafford, A. E. Hamilton, A. M. Buxton,
of Hubei Province (2016CFB537). We are also grateful to
the Analytical and Testing Center of Huazhong
University of Science and Technology, Wuhan, China.
M. C. Bardeaux, J. M. Chalker, J. Org. Chem. 2014, 79, 2094.
[26] B. Li, Z. Guan, W. Wang, X. Yang, J. Hu, B. Tan, T. Li, Adv.
Mater. 2012, 24, 3390.

CHEN ET AL.
9 of 9
[
27] Z. Guan, B. Li, G. Hai, X. Yang, T. Li, B. Tan, RSC Adv. 2014,
, 36437.
[42] M. M. Heravi, E. Hashemi, Y. S. Beheshtiha, S. Ahmadi, T.
4
Hosseinnejad, J. Mol. Catal. A 2014, 394, 74.
[
[
[
28] J. Chen, J. Zhang, D. Zhu, T. Li, J. Porous Mater. 2017, 24, 847.
29] S. Xu, K. Song, T. Li, B. Tan, J. Mater. Chem. A 2015, 3, 1272.
30] J. Chen, J. Zhang, D. Zhu, T. Li, Appl. Organometal. Chem.
[43] B. J. Borah, S. J. Borah, K. Saikia, D. K. Dutta, Appl. Catal. A
2
014, 469, 350.
44] H. Veisi, M. Hamelian, S. Hemmati, J. Mol. Catal. A 2014, 395,
5.
45] B. Inés, I. Moreno, R. SanMartin, E. Domínguez, J. Org. Chem.
008, 73, 8448.
46] J. Cui, M. Zhang, Y. Zhang, Inorg. Chem. Commun. 2010, 13, 81.
[
[
[
2
2
017, https://doi.org/10.1002/aoc.3996.
31] K. Ishihara, S. Ohara, H. Yamamoto, Macromolecules 2000,
3, 3511.
[
[
[
[
[
[
[
[
[
2
3
32] S. Zhou, M. Zhang, R. Wang, J. Ping, X. Zhang, N. Zhao, J. Xu,
Z. Shen, X. Fan, Polymer 2017, 109, 49.
[47] L. Li, J. Wang, C. Zhou, R. Wang, M. Hong, Green Chem. 2011,
3, 2071.
1
33] T. Ahamad, S. M. Alshehri, S. F. Mapolie, Catal. Lett. 2010,
1
38, 171.
[48] N. Fukaya, S. Onozawa, M. Ueda, T. Miyaji, Y. Takagi, T.
Sakakura, H. Yasuda, J. Mol. Catal. A 2014, 385, 7.
34] B. P. Biswal, S. Chandra, S. Kandambeth, B. Lukose, T. Heine,
R. Banerjee, J. Am. Chem. Soc. 2013, 135, 5328.
35] Y. Xu, T. Wang, Z. He, A. Zhong, W. Yu, B. Shi, K. Huang,
SUPPORTING INFORMATION
Polym. Chem. 2016, 7, 7408.
Additional Supporting Information may be found online
in the supporting information tab for this article.
36] M. Mondal, J. Joji, J. Choudhury, Chem. Commun. 2017, 53,
3
185.
37] H. Hamasaki, N. Fukui, S. Fujii, S. Yusa, Y. Nakamura, Colloid
Polym. Sci. 2013, 291, 223.
How to cite this article: Chen J, Zhang J, Sun W,
Song K, Zhu D, Li T. Pd immobilized on polyamide
based on melamine and terephalic acid as an
efficient and recyclable catalyst for Suzuki‐Miyaura
coupling reaction. Appl Organometal Chem. 2017;
e4135. https://doi.org/10.1002/aoc.4135
38] T. Borkowski, J. Dobosz, W. Tylus, A. M. Trzeciak, J. Catal.
2
014, 319, 87.
39] E. A. Karakhanov, A. L. Maksimov, E. M. Zakharian, Y. S.
Kardasheva, S. V. Savilov, N. I. Truhmanova, A. O. Ivanov, V.
A. Vinokurov, J. Mol. Catal. A 2015, 397, 1.
[
[
40] N. A. Bumagin, Catal. Commun. 2016, 79, 17.
41] M. M. Dell'Anna, M. Mali, P. Mastrorilli, A. Rizzuti, C. Ponzoni,
C. Leonelli, J. Mol. Catal. A 2013, 366, 186.