Chitosan nanoparticles functionalized poly-2-hydroxyaniline supported CuO nanoparticles: An efficient heterogeneous and recyclable nanocatalyst for N-arylation of amines with phenylboronic acid at ambient temperature

Article abstract of DOI:10.1002/aoc.6364

The present study aims to prepare an effective and eco-friendly nanocatalyst for the Chan–Lam coupling reaction of phenylboronic acid and amine in aerobic conditions. For this purpose, chitosan was extracted from shrimp shells waste by demineralization, deproteinization, and deacetylation processes and then converted to chitosan nanoparticles (CSN) by the ionic gelation with tripolyphosphate anions. Afterward, poly-2-hydroxyaniline (P2-HA) was grafted to chitosan nanoparticles (NPs) to employ as the support for CuO NPs. Characterization of the nanocatalyst was done using Fourier transform infrared (FT-IR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), mapping, energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). The CuO NPs were identified in the spherical shape with an average size of 17 nm. The prepared nanocatalyst exhibited excellent catalytic performance with a high turnover number (TON) and turnover frequency (TOF) for the Chan–Lam coupling reaction of phenyl boronic acid and amines with different electronic properties. The prepared catalyst could be readily recovered and reused for at least five runs without any noticeable change in structure and catalytic performance. Chitosan (CS) was prepared via demineralization, deproteinization, and deacetylation of shrimp shell and chitosan nanoparticles (CSN) were prepared via ionic gelation process. Polymerization of 2-HA on the CSN surface was done to increase functional groups and create active sites for CuO NPs attachments. CuO NPs-P2-HA-CSN nanocomposite has been shown high efficiently for the Chan–Lam coupling reaction.

Full text of DOI:10.1002/aoc.6364

Received: 27 March 2021
DOI: 10.1002/aoc.6364
Revised: 10 June 2021
Accepted: 22 June 2021
F U L L P A P E R
Chitosan nanoparticles functionalized poly-2-hydroxyaniline
supported CuO nanoparticles: An efficient heterogeneous
and recyclable nanocatalyst for N-arylation of amines with
phenylboronic acid at ambient temperature
Neda Seyedi
| Mahboobeh Zahedifar
Department of Chemistry, Faculty of
Science, University of Jiroft, Jiroft, Iran
Abstract
The present study aims to prepare an effective and eco-friendly nanocatalyst
for the Chan–Lam coupling reaction of phenylboronic acid and amine in
aerobic conditions. For this purpose, chitosan was extracted from shrimp shells
waste by demineralization, deproteinization, and deacetylation processes and
then converted to chitosan nanoparticles (CSN) by the ionic gelation with
tripolyphosphate anions. Afterward, poly-2-hydroxyaniline (P2-HA) was
grafted to chitosan nanoparticles (NPs) to employ as the support for CuO NPs.
Characterization of the nanocatalyst was done using Fourier transform infra-
red (FT-IR), X-ray powder diffraction (XRD), scanning electron microscopy
Correspondence
Neda Seyedi, Department of Chemistry,
University of Jirift, Jiroft, Iran.
Email: nedaseyedi@ujiroft.ac.ir
(SEM), mapping, energy-dispersive X-ray spectroscopy (EDS), transmission
electron microscopy (TEM), and thermogravimetric analysis (TGA). The CuO
NPs were identified in the spherical shape with an average size of 17 nm. The
prepared nanocatalyst exhibited excellent catalytic performance with a high
turnover number (TON) and turnover frequency (TOF) for the Chan–Lam
coupling reaction of phenyl boronic acid and amines with different electronic
properties. The prepared catalyst could be readily recovered and reused for at
least five runs without any noticeable change in structure and catalytic
performance.
Chitosan (CS) was prepared via demineralization, deproteinization, and
deacetylation of shrimp shell and chitosan nanoparticles (CSN) were prepared
via ionic gelation process. Polymerization of 2-HA on the CSN surface was
done to increase functional groups and create active sites for CuO NPs attach-
ments. CuO NPs-P2-HA-CSN nanocomposite has been shown high efficiently
for the Chan–Lam coupling reaction.
K E Y W O R D S
Chan–Lam cross-coupling reaction, chitosan, CuONPs-P2-HA-CSN, heterogeneous
nanocatalyst
Appl Organomet Chem. 2021;e6364.
wileyonlinelibrary.com/journal/aoc
© 2021 John Wiley & Sons, Ltd.
1 of 14
https://doi.org/10.1002/aoc.6364

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SEYEDI AND ZAHEDIFAR
1
| INTRODUCTION
with its imaginary properties such as thermal, electrical,
and catalytic properties was combined with the CS and
[59,60]
Compounds with carbon–nitrogen bonds have become
attractive synthetic targets due to their contribution
toward the synthesis of dyes, agrochemicals, and
applied as a support for catalytic applications.
Herein, in continuing our research on the application of
[
61–63]
heterogeneous catalysts in organic reactions,
the
[1–6]
drugs.
There are many reports in the literature relat-
CuONPs-P2-HA-CSN nanocatalyst was designed and
synthesized to apply in the Chan–Lam cross-coupling
reaction of amine and phenylboronic. In this design, poly
(2-hydroxyaniline) (P2-HA), as a conducting polymer,
was grafted to the CSN in a straightforward method to
synthesize P2-HA-CSN. CuO NPs were decorated on the
surface of the P2-HA-CSN for the preparation of
CuONPs-P2-HA-CSN nanocatalyst.
ing to C–N coupling reactions, such as Ullmann
reaction,
amination,
materials are a predominantly effective catalyst that
conducted using dispersible copper complexes as a
catalyst under homogeneous conditions.
homogeneous catalysts have excellent activity and
selectivity, they are not preferred due to their costly and
unfriendly synthesis and recoverability. Hence, various
homogeneous catalytic processes need to be substituted
with heterogeneous systems.
There are many solid supports for the synthesis of
[7]
[8]
Chan–Lam coupling,
Buchwald–Hartwig
[10]
[9]
and Collman reactions.
Copper-based
[11–13]
Although
2 | EXPERIMENT
[14–20]
2.1 | Materials and chemical
instruments
[21–38]
heterogeneous and also Cu nanocatalysts.
Polymer-
stabilized metal nanoparticles have recently attracted
much attention as a new research path in catalysts inves-
All materials, acetic acid, sodium polytriphosphate,
ammonium persulfate (APS), sodium borohydride
(NaBH ), potassium carbonate (K CO ), sodium phos-
[39–42]
tigations.
The polymer matrices have been applied
as the stabilizer and support of nanoparticles to prevent
aggregation. Among them, biopolymers such as chitosan
4
2
3
phate (Na PO ), potassium hydroxide (KOH), triethyl
3
4
(CS), cellulose (cell), gelatin, starch, and agar (AG) are
amine (ET N), amines, imidazole, benzimidazole, phe-
3
the most explored ones due to the excellent chemical and
biological properties.
nylboronic acid, CuCl .6H O, and solvents were procured
2
2
from the Merck/Aldrich chemical company and used
without further purification. The Fourier transform infra-
red (FT-IR) spectra were recorded with KBr pellet on a
Bruker tensor 27 FT-IR spectrometer with RT-DLATGS
detector. The powder X-ray diffraction (XRD) patterns
were examined on a model X'PertPro diffractometer
(Panalytical, Almelo, the Netherlands) using Cu Kα radi-
ation (wavelength = 1.54 Å). The CuONPs-P2-HA-CSN
size and morphology were characterized applying a trans-
mission electron microscopy (TEM; EM10c-100 kV) and
field emission scanning electron microscopy (SEM),
and energy-dispersive X-ray spectroscopy (EDS), using
SIGMA VP from Carl Zeiss Inc., Jena, Germany), The
thermal stability of the synthesized CuONPs-P2-HA-
CSN was studied using TGA (STA503, Germany).
CS is a high molecular weight polysaccharide that
contains (1,4)-linked-2-deoxy-2-amino-d glucopyranose
units and active amino and hydroxyl functional groups.
This biopolymer can be obtained from N-deacetylation of
[43]
chitin or fishery waste.
Chitosan nanoparticles (CSN)
have a great deal of attention because of their nano-size,
large surface area, biodegradability, and good biocompat-
ibility. All these characteristics make CSN an appropriate
choice in a wide range of applications, including drug
[
44]
[45]
[46]
delivery systems,
removal of pollution,
sensors,
protein carriers,
[
47]
[48]
and catalysts.
Although CSN
contains essential and objective properties, poor electrical
conductivity and unfortunate stability make them away
[49]
from motivation response.
To overcome these
drawbacks, the active groups of CSN can be coupled with
[50,51]
other conductive polymers.
Conjugated conducting polymers, including poly-
aniline and its derivatives, polythiophene, and
polypyrrole, are a class of widely studied materials due to
their attractive applications in electronics, biosensors,
2.2 | Synthesis
2.2.1 | Extraction of CS
[52–55]
actuators, and photothermal therapy.
One of the
1. Demineralization process: this process was done by
mixing shrimp shells powder with a solution of HCl
(4%) in a ratio of 1:14 (w/v) at ambient temperature
for 24 h under vigorous stirring. Then, the product
was washed with distilled water till neutralized and
most usually used conducting polymers is polyaniline
and its derivatives because of its easy synthesis, high
[
56,57]
conductivity, and good environmental stability.
Reportedly, by combining CS and PANI derivatives, CS
[58]
ꢀ
properties can promote.
In a few studies, the PANI
dried under vacuum at 60 C.

SEYEDI AND ZAHEDIFAR
3 of 14
2
. Deproteinization process: this process was carried out
by mixing demineralized powder and NaOH (5%) in a
ratio of 1:12 (w/v) at 90 C for 24 h under vigorous
2.3 | Catalytic activity of CuONPs-
P2-HA-CSN nanocatalyst
ꢀ
stirring. The product was washed with distilled water
till neutralized and dried under vacuum at 60 C.
In a typical procedure, a mixture of amine (2.0 mmol),
ꢀ
phenylboronic acid (1 mmol), K CO3 (2 mmol), and
2
3
. Deacetylation: in the final step deacetylation was done
by mixing the deproteinized product with NaOH
CuONPs-P2-HA-CSN (4.2 mol%) nanocatalyst in 10 ml of
H O-EtOH (1:1) was stirred at ambient temperature.
2
(
70%) in a ratio of 1:14 (w/v) at ambient temperature
After confirming the end of the process by thin-layer
chromatography (TLC), the mixture was diluted with
water. The catalyst was removed by centrifuge and subse-
quently washed with dichloromethane for successive
cycles. The pure product was obtained by column chro-
matography (60–120 mesh silica gel) using hexane/ethyl
acetate (9:1) solvent.
for 75 h under vigorous stirring. Then, the chitosan
product was washed with distilled water till
neutralized and dried under vacuum at 60 C.
ꢀ
2
.2.2 | Preparation of CSN
A 0.5% (w/v) solution of CS in acetic acid (0.1%, v/v) was
prepared and stirred at ambient temperature for 24 h.
Then a solution of sodium polytriphosphate (TPP) in
deionized water (0.25% w/v, 2 ml) was added to 6 ml of
the prepared chitosan solution and stirred (600 rpm) for
3 | RESULT AND DISCUSSION
3.1 | Synthesis and characterization of
CuONPs-P2-HA-CSN nanocatalyst
3
0 min at ambient temperature. The final supernatant
ꢀ
was freeze-dried to produce CSN and stored at 4 C until
further use.
In this research, a simple, economic, and efficient
methodology was used for the synthesis of CuONPs-
P2-HA-CSN. Shrimp shell wastes were employed to
synthesize CS by demineralization, deproteinization, and
deacetylation processes. The obtained CS was turned to
CSN by a stable and non-toxic ionotropic gelation
method. The CS NPs have the wide-ranging properties of
CS and some properties of nanomaterials such as quan-
[64]
2.2.3 | Synthesis of P2-HA-CSN
The chemical oxidative polymerization reaction was car-
ried out in a well-stoppered flask of 250-ml capacity.
Briefly, 0.10 g of CSN was dissolved in an aqueous
solution of acetic acid (50 ml, 2%) followed by the
addition of 1.09 g of 2-HA and stirred for 1 h under
nitrogen atmosphere. Then, the APS solution (0.570 g in
[
65]
tum size, surface, and interface effects.
There are only
a few reports on the application of CSN in catalytic sys-
tems. Grafting P2-HA on the surface of the CSN increases
functional groups and active sites for CuO NPs attach-
ment. In-situ polymerization of 2-HA on the CSN surface
simplified preparation of P2-HA-CSN (Scheme 1).
1
0-ml H O) was added dropwise to the reaction mixture
2
with continuous stirring. The reaction mixture was kept
with constant stirring under the nitrogen atmosphere
overnight. After that, the resulting precipitate was filtered
using the Buchner funnel and washed thoroughly with
distilled water and methanol. Finally, the product was
The XRD patterns of the fresh CuONPs-P2-HA-CSN,
recovered CuONPs-P2-HA-CSN, P2-HA-CSN, CSN, and
CS are shown in Figure 1a–d. The diffraction patterns of
CuO NPs in both fresh recovered CuONPs-P2-HA-CSN
ꢀ
ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ
dried at 60 C for 12 h.
are located at 2θ = 31.8 , 35.2 , 38.5 , 48.7 , 53.5 , 58.3 ,
ꢀ
ꢀ
6
1.5 , and 66.5 , corresponding to (110), (002), (111),
(
200), (20–2), (002), (113), and (220) planes, respectively
2
.2.4 | Synthesis of CuONPs-P2-HA-CSN
(Figures 1a,b). Similar diffraction peaks of the fresh and
recovered nanocatalyst after the five runs, suggesting sta-
bility and robustness of the CuONPs-P2-HA-CSN during
the reaction and recovery process. The diffraction peaks
of CuO NPs are in agreement with the monoclinic phase
with the space group of C2/c, which indicates the prepa-
ration of pure crystalline phase of CuO NPs based on the
nanocatalyst
Three hundred milligrams of the prepared P2-HA-CSN
was added to the aqueous solution of CuCl (200 ml,
6
energy for 5 min. After that, pH of the mixture was
adjusted to 12 by the addition of NaOH solution (0.2 M)
and refluxed at 100 C for 24 h. The resulting product was
collected by centrifuge and dried at 100 C under vacuum
to obtain CuONPs-P2-HA-CSN nanocatalyst.
2
M) in a 500-ml three-necked flask and sonicated at low
joint committee powder diffraction standards data
ꢀ
[66]
(JCPDS Card No. 01-080-1268).
The average crystallite
ꢀ
size of CuO NPs is calculated by Debye–Scherrer
equation; [D = kλ/βcos(θ)], which D presents the average

4
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SEYEDI AND ZAHEDIFAR
SCHEME 1 Schematic illustration for the preparation of CuONPs-P2-HA-CSN
FIGURE 1 The X-ray powder diffraction (XRD) pattern of (a) fresh CuONPs-P2-HA-CSN, (b) recovered CuONPs-P2-HA-CSN,
c) P2-HA-CSN, and (d) CS and CS NPs
(
crystal size, k is the Scherrer coefficient (0.9), λ represents
X-ray wavelength (1.54 Å), β is the full width half maxi-
but after crosslinking with tripolyphosphate, CSN shows
a decrease in crystallinity and peaks intensity (Figure 1d).
It can be attributed to the decreasing of the hydrogen
[
21]
mum (FWHM) intensity, and θ is the diffraction angle.
The average crystalline size of CuO NPs is computed
[
67–69]
bonds of CSN compared to CS.
peaks at 2θ = 10.0 –20.0 are attributed to the 2-HA poly-
mer (Figure 1c) in CuONPs-P2-HA-CSN nanocatalyst
Sharp diffraction
ꢀ
ꢀ
ꢀ
ꢀ
1
7 nm. Broad peaks at 2θ = 20.0 and 10.7 are related to
CSN as presented in Figure 1d. The amorphous structure
of CS NPs was created during the formation process of
CSN from CS. The structure of CS molecules contains a
certain regularity and can form a crystalline structure,
[
70]
with the crystalline/amorphous phases.
SEM images of the fresh and recovered CuONPs-
P2-HA-CSN catalyst are presented in Figure 2a,b. The

SEYEDI AND ZAHEDIFAR
5 of 14
FIGURE 2 Scanning electron microscopy (SEM) images of (a) fresh CuONPs-P2-HA-CSN, (b) recovered CuONPs-P2-HA-CSN, and
c) energy-dispersive X-ray spectroscopy (EDS) pattern of fresh CuONPs-P2-HA-CSN
(
SEM image of the fresh CuONPs-P2-HA-CSN
nanocatalyst confirmed the successful synthesis of the
polymeric structure and its composition with CuO NPs
the CuONPs-P2-HA-CSN nanocatalyst. The distribution
of each element is demonstrated in EDS mapping of the
nanocatalyst (Figure 3). The CuONPs-P2-HA-CSN com-
position is in correspondence with the elemental compo-
sition, and elements are uniformly distributed. According
to Figure 3, oxygen and copper are dispersed uniformly
on the P2-HA-CSN surface, illustrating the successful
interaction between CuO and substrate.
TEM images (Figure 4) of CuONPs-P2-HA-CSN
nanocatalyst confirmed the successful synthesis of the
polymeric matrix and CuO nanocatalyst. It could be
observed that spherical CuO NPs with an average size
ranging from 10 to 17 nm embedded over the P2-HA-
CSN matrix after the chemical reduction process. As visi-
ble in Figure 4a,b, structure and morphology of recovered
(Figure 2a). The CuO NPs as the embedded particles over
the P2-HA-CSN matrix are almost spherical with an aver-
age size of 17 nm. As shown in the SEM image of the
recovered catalyst (Figure 2b), the structure and
morphology of CuONPs-P2-HA-CSN nanocatalyst were
kept without any significant changes after five runs
(Figures 2a,b). The EDS analysis of the CuONPs-P2-HA-
CSN nanocatalyst is shown in Figure 2c. The successful
synthesis of CuONPs-P2-HA-CSN was confirmed by the
visual elemental composition of Cu, O, N, and C in
Figure 2c. Furthermore, the elemental mapping analysis
was done to discover the distribution of the elements in

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SEYEDI AND ZAHEDIFAR
FIGURE 3 Energy-dispersive X-ray spectroscopy (EDS) mapping of the CuONPs-P2-HA-CSN
FIGURE 4 Transmission electron microscopy (TEM) images of (a) fresh CuONPs-P2-HA-CSN and (b) recovered CuONPs-P2-HA-CSN
[
71]
CuONPs-P2-HA-CSN nanocatalyst are retained after
five runs.
OH groups.
Symmetric and asymmetric stretching
ꢁ
1
vibrations of CH are placed at 2922 and 2852 cm
(Figure 5a).
2
[
71]
The FT-IR spectra of the CSN, P2-HA-CSN, and
CuONPs-P2-HA-CSN are presented in Figure 5a–d.
Grafting of P2-HA-CSN onto CSN and its assembling to
CuO NPs is provable from Figure 5a–d by the following
features. Strong and board absorption bonds between
The P=O stretching vibration of
ꢁ
1
tripolyphosphate in CSN appeared around 1161 cm
[
72]
(Figure 5a).
By grafting P2-HA onto CSN (Figure 5b),
the stretching vibration of OH and NH groups was
ꢁ
1
73
located at 3411 and 3193 cm , respectively. The peak
ꢁ
1
ꢁ1
3
500 and 3400 cm
in the FT-IR spectra of CSN
at 1373 cm is attributed to CN stretching vibration or
(
Figure 5a) are due to stretching vibrations of NH and
combination bands of asymmetric bending and torsional
2

SEYEDI AND ZAHEDIFAR
7 of 14
ꢀ
ꢀ
degradable in a temperature range of ꢂ400 C to 1000 C.
As shown in Figure 6a, degradation of CuONPs-
P2-HA-CSN is started around 150 C. Due to the existence
ꢀ
of polar groups in CuONPs-P2-HA-CSN nanocatalyst,
water can easily absorb into the composite by hydrogen
[
75,76]
bonding.
Therefore, the initial loss of weight is due
ꢀ
to water removal. Decreasing the weight from 140 C
to 240 C is probably due to eliminating small molecules
such as NH3.
ꢀ
[
71]
ꢀ
Weight loss after 240 till 350 C maybe is
due to the degradation of the polymer matrix and the
[
71]
ꢀ
crosslinking break.
At 450 C, 50% of CuONPs-P2-HA-
ꢀ
CSN nanocatalyst are lost, and at 700 C, 28% of the sam-
ple remained, which indicates the catalyst's high thermal
stability.
DTA can provide further information on the thermal
transition of the CuONPs-P2-HA-CSN nanocatalyst
(
Figure 6b). During the DTA measurement, two signifi-
cant peaks are displayed. The temperature values are
ꢀ
ꢀ
around 400 C and 700 C, which are consistent with the
TGA results.
3.2 | The catalytic activity of CuONPs-
P2-HA-CSN nanocatalyst in C–N cross-
FIGURE 5 The Fourier transform infrared (FT-IR) spectra of
coupling reaction
(
a) chitosan nanoparticles (CSN), (b) P2-HA-CSN, and (c) fresh
CuONPs-P2-HA-CSN and (d) recovered CuONPs-P2-HA-CSN
After characterizing the prepared CuONPs-P2-HA-CSN
nanocatalyst, its catalytic activity was studied in the
cross-coupling reaction of amine with phenylboronic
acid. To optimize the reaction condition (Scheme 2),
[
74]
oscillation of the protonated amine group (Figure 5b).
ꢁ
1
The stretching vibration peak at 1530 cm
can be
the
cross-coupling
reaction
of
aniline
with
[
73]
assigned to C=C in the polymer structure (Figure 5b).
phenylboronic acid was chosen as a model reaction. As
shown in Table 1, almost no desired product was
detected when the reaction mixture was stirred
for 10 h in the presence of CuONPs-P2-HA-CSN
nanocatalyst (6.3 mol%) at ambient temperature in the
absence of any solvent (Table 1, Entry 1). Pleasantly,
the yield of the product was increased when the reac-
tion was performed in dichloromethane, acetonitrile,
ethanol, and water (Table 1, Entries 2–5). Among these
Also, out of C–H deformation peaks presented the
substitution in the benzene ring of P2-HA appear at
ꢁ
1
8
18 and 757 cm , but these absorption peaks did not
[73]
appear in the case of chitosan (Figure 5b).
After
assembling CuO NPs on the P2-HA-CSN, the peaks at
ꢁ
1
6
00–800 cm shifted to the higher wavelength region,
indicating the interactions between CuO and 2-HA,
which are happened through π–π* of quinoid rings and
[61]
required less energy (Figure 5c).
Infrared (IR) results
solvents, EtOH/H O system acted better for enhancing
2
confirm the successful synthesis of CuONPs-P2-HA-CSN
nanocatalyst. Further studies on the recoverability of
CuONPs-P2-HA-CSN nanocatalyst were carried out by
recording the FT-IR spectrum of the recovered catalyst
the yield of the related product. The effect of catalyst
loading was also investigated to determine the opti-
mum catalyst amount for preparing the target product.
It should be noted that no reaction was observed in
the absence of the catalyst (Table 1, Entry 13). The
results demonstrated that 4.2 mol% of the catalyst was
the optimum amount of catalyst for completing the
reaction. By increasing the catalyst amount to 6.3 mol
%, no significant enhancement in the reaction yield
was found. In contrast, the prolongation of the reaction
time was observed by decreasing the catalyst amount
to 2.1 mol%.
(Figure 5d). Similar IR spectral data of fresh and reused
catalysts show preserving the functional groups of
reused catalyst and suggest stability and robustness of the
CuONPs-P2-HA-CSN in this protocol.
The thermal stability of the prepared CuONPs-
P2-HA-CSN
nanocatalyst
was
investigated
by
TGA–differential thermal analysis (DTA) analysis and
represented in Figure 6a,b. CuONPs-P2-HA-CSN is

8
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SEYEDI AND ZAHEDIFAR
FIGURE 6 (a) Thermogravimetric analysis
(
(
TGA) and (b) differential thermal analysis
DTA) analysis of CuONPs-P2-HA-CSN
SCHEME 2 Synthesis of diphenylamine derivatives
in the presence of CuONPs-P2-HA-CSN
Thus, EtOH/H O as a solvent, K CO as a base, and
.2 mol% of catalyst amount were applied as the optimal
mixture after 3 h while the reaction was continuing.
There was no increase in the reaction progress after an
additional 5 h, which indicated the heterogeneous
characteristics of the CuONPs-P2-HA-CSN nanocatalyst.
The inductively coupled plasma spectrometry (ICP-OES)
analysis showed that the amount of Cu leaching into the
reaction mixture is meager (0.7 ppm). Furthermore,
the (ICP-OES) analysis showed that more than 90% of
CuO NPs were still coated on the catalyst after five cycles.
The initial concentration of copper in the fresh catalyst
was 26.67 wt%, while the weight percentage for the
recovered catalyst was 25.3 wt% after five runs). These
results are confirmed by analytical data of the fresh and
reused catalysts (Figures 1, 2, 4, and 5).
2
2
3
4
conditions in an open flask at ambient temperature in
further studies (Table 1, Entry 11). As well as the
catalytic activity, the recoverability and reusability of the
catalyst is the most important benefit in the practical
application of heterogeneous catalysis. The catalyst was
separated from the reaction mixture by centrifuge,
washed with methanol, and dried under vacuum for the
next cycle.
The results presented that the prepared catalyst could
be recovered and recycled at least five times without any
significant changes in its reactivity and original structure
for the model reaction (Figure 7), mainly due to the
excellent stability of CuONPs-P2-HA-CSN nanocatalyst.
Additional studies on the stability of the catalyst were
done by separating nanocatalyst from the reaction
After optimizing the reaction conditions, the possibil-
ity and activity of the CuONPs-P2-HA-CSN nanocatalyst
were further explored for aerobic C–N cross-coupling

SEYEDI AND ZAHEDIFAR
9 of 14
TABLE 1 C–N cross-coupling reaction with CuONPs-P2-HA-CSN
a,b
Entry
Solvent
Base
Amount of catalyst (mol%)
Time (h)
Yield (%)
1
2
3
4
5
6
6
7
8
9
Nonsolvent
K
K
K
K
K
K
2
2
2
2
2
2
CO
CO
CO
CO
CO
CO
3
3
3
3
3
3
6.3
6.3
6.3
6.3
6.3
6.3
6.3
6.3
6.3
6.3
6.3
4.2
2.1
0
10
10
10
10
10
10
10
10
10
8
Trace
45
2 2
CH Cl
Acetonitrile
EtOH
65
75
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
O
80
O/EtOH
O/EtOH
O/EtOH
O/EtOH
O/EtOH
O/EtOH
O/EtOH
O/EtOH
O/EtOH
O/EtOH
O/EtOH
O/EtOH
O/EtOH
O/EtOH
95
Et3N
KOH
-
30
66
Trace
95
K
K
K
K
K
K
K
K
K
K
2
2
2
2
2
2
2
2
2
2
CO
CO
CO
CO
CO
CO
CO
CO
CO
CO
3
3
3
3
3
3
3
3
3
3
1
1
1
1
1
1
1
1
1
0
1
2
3
4
5
6
7
8
6
65
8
95
8
70
8
0
c
d
e
f
4.2
4.2
4.2
4.2
4.2
8
76
8
96
8
70
8
60
g
8
Trace
a
2 3
Reaction conditions: phenylboronic acid (1 mmol), aniline (2 mmol), solvent (10 ml), K CO (2 mmol), and ambient temperature.
b
Isolated yield.
mmol of K CO
CO
mmol phenylboronic acid.
c
1
2
3
.
d
3
mmol of K
2
3
.
e
2
f
0
.75-mmol phenylboronic acid.
g
Nitrogen atmosphere was used.
assumed in Table 2. The use of various aryl amines
reveals that aryl amines containing electron-donating
groups exhibited slightly better results than those with
electron-withdrawing substituents. Investigations on the
steric effects around amino functionality of the aniline
derivatives were done by the reaction of ortho-substituted
anilines with phenylboronic acid. Results showed that
even in the presence of steric effects, the formation of
N,N-diaryl amines is favorable in the cross-coupling reac-
tion under the reaction conditions (Table 2, Entries 1, 3,
4, 6, and 8). Also, in the reaction of phenylboronic acid
with aniline bearing the strong electron-withdrawing –
NO group, no product formation was observed even
2
after a long time (Table 2, Entry 12). The yield of N,N-
diaryl amines was slightly decreased when the desired
reaction was performed by 4-chloroaniline (Table 2,
Entry 10), 2-bromoaniline (Table 2, Entry 8), and
FIGURE 7 Reusability of catalyst in the C–N cross-coupling
reaction of phenylboronic acid and aniline under optimized
reaction conditions
4-bromoaniline (Table 2, Entry 9). The side products
reaction of different substituted amines with phe-
nylboronic acid for the formation of N,N-diaryl amines in
good to excellent yields. The experimental data are
resulting from the Suzuki cross-coupling reaction are
the main reason for this decrease. Furthermore, the good
leaving nature of the bromo group might be responsible

10 of 14
SEYEDI AND ZAHEDIFAR
TABLE 2 Synthesis of diphenylamine derivatives in the presence of CuONPs-P2-HA-CSN
ꢁ
1
ꢀ
Entry
Amine compounds
Time (h)
Yield (%)
TON
TOF (h
)
m.p. ( C)
Reference
[
77]
1
8
89
21.19
2.65
30–31
Dutta and Phukan
[
78]
2
3
8
8
96
90
22.86
21.42
2.86
2.68
89–90
Ackermann et al.
[
79]
oil
Rout et al.
[
80]
4
5
8
8
92
97
22
23
2.74
2.89
oil
Raghuvanshi et al.
[
78]
106–107
Ackermann et al.
[
81]
6
7
8
8
86
96
20.48
22.86
2.56
2.86
78–80
68–69
Liang et al.
[
82]
Roscales and Cs ꢀa kÿ

SEYEDI AND ZAHEDIFAR
11 of 14
TABLE 2 (Continued)
ꢁ
1
ꢀ
Entry
Amine compounds
Time (h)
Yield (%)
TON
TOF (h
)
m.p. ( C)
Reference
[
83]
8
8
84
20
2.5
oil
Vantourout et al.
[
79]
9
8
8
80
89
19.04
2.4
88–89
Rout et al.
[
79]
1
0
21.2
2.65
71–72
Rout et al.
[
80]
1
1
1
2
8
8
95
22.62
2.83
50–51
Raghuvanshi et al.
0
0
0
–
–
[
83]
1
3
4
8
8
77
70
17.86
16.66
2.23
2.08
Oil
Oil
Vantourout et al.
[
84]
1
Marzo et al.
[
79]
1
5
11
85
20.24
1.84
Yellow oil
Rout et al.
(
Continues)

12 of 14
SEYEDI AND ZAHEDIFAR
TABLE 2 (Continued)
ꢁ
1
ꢀ
Entry
Amine compounds
Time (h)
Yield (%)
TON
TOF (h
)
m.p. ( C)
Reference
[
79]
1
6
11
88
20.95
1.90
94–95
Rout et al.
2 3
Note: Reaction conditions: amine (2 mmol), phenylboronic acid (1 mmol), K CO (2 mmol), and catalyst (4.2 mol%). TON and TOF can be determined based
on the amount of product biaryl amine which was formed.
Abbreviations: TON, turnover number = (mol of product/mol of catalyst); TOF, turnover frequency = (TON/time [h]).
TABLE 3 Comparison of CuONPs-P2-HA-CSN nanocatalyst with other reported heterogeneous catalytic systems in C–N cross-coupling
of amine with phenylboronic acid
Temperature
( C)
Time
(h)
Yield
(%)
ꢀ
Entry Catalyst
Solvent Base
TON TOF Reference
[
85]
1
2
MPI-Cu(1:1)
Fe @SiO
DCM
-
R.T.
R.T.
24
3
32
78
3.2
0.13
Biffis et al.
3
O
4
2
/APTES/
H
2
O
3 4
Na PO
1.59 0.53
Shahabi Nejad
[
24]
IMMPh@Ni2+
et al.
[
86]
3
4
Cu-polymer supported
DMSO
K
2
CO
3
140
12
24
86
79
33
2.75
0.66
Islam et al.
Cu (OAc)
NiCl .6H
CuO NPs
CuONPs-P2-HA-CSN
2
, myristic acid
toluene
2,6-lutidine R.T.
15.8
Antilla and
[
87]
Buchwald
0
5
6
7
2
2
O, 2,2 bipyridl
CH
3
CN
DBU
R.T.
R.T.
R.T.
20
8
78
92
95
3.9
0.2
Raghuvanshi
[
80]
et al.
[
88]
MeOH/
H O
2
K
K
2
2
CO
3
3
3.6
0.38
2.83
Borah et al.
EtOH/
CO
8
22.6
This study
2
H O
Abbreviations: TOF, turnover frequency; TON, turnover number; R.T., room temperature.
for decreasing C–N cross-coupling in the 4-bromo
Comparing our results with other reported catalytic
aniline.
systems in the Chan–Lam cross-coupling reaction of
amine and phenylboronic acid demonstrates that the pre-
pared CuONPs-P2-HA-CSN nanocatalyst exhibits more
favorable results under mild conditions. (Table 3).
Other amines, including imidazole, benzimidazole,
and aliphatic amines, were experimented with in
this reaction for more development about the potential
of this protocol. The corresponding cross-coupling
products successfully produced in moderate to good
yield.
4 | CONCLUSIONS
TONs and TOFs of CuONPs-P2-HA-CSN nanocatalyst
are listed in Table 2. The CuONPs-P2-HA-CSN catalyst
yielded remarkable TON and TOF values by using a sim-
ple, fast, and eco-friendly method. These findings reveal
that P2-HA-CSN can be suitable support material for a
copper catalyst from economic standpoints.
In summary, CuONPs-P2-HA-CSN nanocatalyst was
successfully prepared from commercially available and
low-cost substances in a straightforward method. The
new heterogeneous copper composite was applied as
the efficient, green, and economic catalyst to synthesize

SEYEDI AND ZAHEDIFAR
13 of 14
N-arylated products by the Chan–Lam cross-coupling
reaction of various amines with phenylboronic acids in a
green solvent at ambient temperature under air.
Applying the CuONPs-P2-HA-CSN nanocatalyst in this
reaction contained valuable results such as using a few
amounts of catalyst to enhance the reaction progress, a
wide range of substrate tolerance, and facile protocol for
the synthesis of N-arylated products using a wide range
of aliphatic and aromatic amines. Moreover, the process
provides the attractiveness of the recyclability of the cata-
lyst without any considerable loss of activity for at least
five cycles that making the process more environmentally
acceptable.
[11] D. M. Chan, K. L. Monaco, R. P. Wang, M. P. Winters, Tetra-
hedron Lett. 1998, 39(19), 2933.
[
[
[
12] P. Y. Lam, C. G. Clark, S. Saubern, J. Adams, M. P. Winters,
D. M. Chan, A. Combs, Tetrahedron Lett. 1998, 39(19), 2941.
13] A. P. Combs, S. Saubern, M. Rafalski, P. Y. Lam, Tetrahedron
Lett. 1999, 40(9), 1623.
14] A. Maleki, E. Akhlaghi, R. Paydar, Appl. Organometal. Chem.
2016, 30(6), 382.
[15] A. Maleki, N. Nooraie Yeganeh, Appl. Organometal. Chem.
017, 31(12), e3814.
2
[16] A. Maleki, R. Ghalavand, R. Firouzi Haji, Appl. Organometal.
Chem. 2018, 32(1), e3916.
[17] A. Maleki, N. Hamidi, S. Maleki, J. Rahimi, Appl. Organo-
metal. Chem. 2018, 32(4), e4245.
[
[
18] Z. Varzi, A. Maleki, Appl. Organometal. Chem. 2019, e5008.
19] S. Mortazavi-Derazkola, M. Salavati-Niasari, O. Amiri, A.
Abbasi, J. Energy Chem. 2017, 26(1), 17.
ACKNOWLEDGMENTS
The authors express appreciation to the University of
Jiroft Faculty Research Committee for supporting this
investigation.
[20] M. Salavati-Niasari, Z. Fereshteh, F. Davar, Polyhedron 2009,
8(1), 126.
2
[21] N. Seyedi, K. Saidi, H. Sheibani, Catal. Let. 2018, 148(1), 277.
22] M. Zahedifar, M. Shirani, A. Akbari, N. Seyedi, Cellulose 2019,
[
2
6(11), 6797.
AUTHOR CONTRIBUTIONS
[
23] N. Amirmahani, N. O. Mahmoodi, M. Malakootian, A.
Pardakhty, N. Seyedi, Res. Chem. Intermed. 2020, 46(10), 4595.
24] M. Shahabi Nejad, N. Seyedi, H. Sheibani, S. Behzadi, Mol.
Diversity 2019, 23(3), 527.
Neda Seyedi: Data Curation; formal analyss; Investiga-
tion; methodology; project administration; supervision.
Mahboobeh Zahedifar: Data curation; formal analysis;
investigation; methodology; project administration;
supervision.
[
[25] N. Seyedi, M. Shahabi, K. Saidi, H. Sheibani, C. R. Chim. 2020,
3(1), 63.
2
[
[
[
[
[
[
[
26] M. Zarei, N. Seyedi, S. Maghsoudi, M. Shahabi Nejad, H.
Sheibani, Inorg. Chem. Commun. 2021, 123, 108327.
27] M. Zarei, N. Seyedi, S. Maghsoudi, M. Shahabi Nejad, H.
Sheibani, J. Chin. Chem. Soc. 2020, 67(11), 1992.
28] F. Tavakoli, M. Salavati-Niasari, F. Mohandes, Mater. Res. Bull.
2015, 63, 51.
DATA AVAILABILITY STATEMENT
The data that support the findings of this study are
available from the corresponding author upon reasonable
request.
29] M. Masjedi-Arani, M. Salavati-Niasari, Int. J. Hydrogen Energy
2
017, 42(27), 17184.
ORCID
30] F. Beshkar, H. Khojasteh, M. Salavati-Niasari, J. Colloid Inter-
face Sci. 2017, 497, 57.
31] S. Zinatloo-Ajabshir, M. Salavati-Niasari, Z. Zinatloo-Ajabshir,
Mater. Lett. 2016, 180, 27.
32] A. Salehabadi, M. Salavati-Niasari, M. Ghiyasiyan-Arani,
J. Alloys Compd. 2018, 745, 789.
Neda Seyedi https://orcid.org/0000-0002-7455-4669
Mahboobeh Zahedifar https://orcid.org/0000-0001-
5
380-7076
REFERENCES
[
1] T. Wiglenda, I. Ott, B. Kircher, P. Schumacher, D. Schuster, T.
Langer, R. Gust, J. Med. Chem. 2005, 48(20), 6516.
2] Z. Jin, Nat. Prod. Rep. 2005, 22(2), 196.
3] I. V. Seregin, V. Gevorgyan, Chem. Soc. Rev. 2007, 36(7), 1173.
4] T. Wiglenda, R. Gust, J. Med. Chem. 2007, 50(7), 1475.
5] D. G. Hulcoop, M. Lautens, Org. Lett. 2007, 9(9), 1761.
6] C. Xie, Y. Zhang, Z. Huang, P. Xu, J. Org. Chem. 2007, 72(14),
[33] S. K. Das, B. K. Chandra, S. A. Molla, M. Sengupta, S. M.
Islam, A. Majee, A. Bhaumik, Mol. Catal. 2020, 480, 110650.
[34] I. Dindarloo Inaloo, S. Majnooni, H. Eslahi, M. Esmaeilpour,
New J. Chem. 2020, 44(31), 13266.
[35] I. Dindarloo Inaloo, M. Esmaeilpour, S. Majnooni, A. Reza
Oveisi, ChemCatChem 2020, 12(21), 5486.
[
[
[
[
[
[36] Z. Sun, S. Yu, L. Zhao, J. Wang, Z. Li, G. Li, Chem. – Eur. J.
2018, 24(42), 10829.
5
431.
[
7] A. M. Nikoli ꢀc , J. Stani ꢀc , M. Zlatar, M. Gruden, B. Andelkovi ꢀc ,
Z. Selakovi ꢀc , V. Ajda cˇ i ꢀc , I. M. Opsenica, J. Org. Chem. 2021, 86
[37] I. I. Dindarloo Inaloo, S. Majnooni, H. Eslahi, M.
Esmaeilpour, Mol. Catal. 2020, 492, 110915.
(
6), 4794.
8] R. P. Wexler, P. Nuhant, T. J. Senter, Z. J. Gale-Day, Org. Lett.
019, 21(12), 4540.
[38] A. R. Sardarian, I. Dindarloo Inaloo, M. Zangiabadi, Catal.
Lett. 2018, 148(2), 642.
[39] F. Ansari, A. Sobhani, M. Salavati-Niasari, Magn. Magn.
Mater. 2016, 410, 27.
[
[
2
9] T. Mizusaki, K. Matsumoto, K. Takeuchi, N. Fukaya, Y.
Takagi, J. C. Choi, Organometallics 2019, 38(9), 1872.
10] J. P. Collman, M. Zhong, Org. Lett. 2000, 2(9), 1233.
[40] N. Salam, S. K. Kundu, A. S. Roy, P. Mondal, S. Roy, A.
Bhaumik, S. M. Islam, Catal. Sci. Technol. 2013, 3(12), 3303.
[

14 of 14
SEYEDI AND ZAHEDIFAR
[
41] M. Choudhary, R. Islam, M. Witcomb, K. Mallick, Dalton
Trans. 2014, 43(17), 6396.
Castillo-Ortega, M. S. Yépiz-G ꢀo mez, M. Plascencia-Jatomea,
Carbohydr. Polym. 2010, 82(2), 305.
[
42] S. Mahato, R. Islam, C. Acharya, M. Witcomb, K. Mallick,
ChemCatChem 2014, 6(5), 1419.
[68] A. R. Raut, S. R. Khairkar, World J Pharm Res. 2014, 3, 523.
[69] K. Vijayalakshmi, B. M. Devi, P. N. Sudha, J. Venkatesan, S.
Anil, J Nanomed Nanotechnol 2016, 7(6), 419.
[70] G. Thenmozhi, P. Arockiasamy, R. Jaya Santhi, Int.
J. Electrochem. Sci. 2014.
[
43] I. Younes, M. Rinaudo, Mar. Drugs. 2015, 13(3), 1133.
44] A. Bernkop-Schnürch, S. Dünnhaupt, Eur. J. Pharm.
Biopharm. 2012, 81(3), 463.
[
[
[
45] C. Li, Z. Wu, H. Yang, L. Deng, X. Chen, Sensor Actuat
B-Chem. 2017, 251, 446.
46] P. Calvo, C. Remunan-Lopez, J. L. Vila-Jato, M. J. Alonso,
J. Appl. Polym. Sci. 1997, 63(1), 125.
[71] T. Gomathi, C. Govindarajan, M. H. Rose, P. N. Sudha, P. M.
Imran, J. Venkatesan, S. K. Kim, Int. J. Pharm. 2014,
468(1–2), 214.
[72] L. Wang, A. Wang, J. Hazard. Mater. 2007, 147(3), 979.
[73] M. S. Ibrahim, H. R. Abd El-Mageed, H. M. Abd El-Salam,
Polym. Bull. 2019, 1.
[47] J. Wang, S. Zhuang, Crit Rev Env Sci Tec. 2017, 47(23), 2331.
48] D. J. Macquarrie, J. J. Hardy, Ind. Eng. Chem. Res. 2005, 44
[
(
23), 8499.
[74] H. M. Abd El-Salam, E. H. Kamal, M. S. Ibrahim, J. Polym.
Environ. 2017, 25(4), 973.
[
[
[
[
[
[
[
49] H. Huang, J. Wu, X. Lin, L. Li, S. Shang, M. C.-W. Yuen, G.
Yan, Carbohydr. Polym. 2013, 95(1), 72.
50] A. Konwar, S. Kalita, J. Kotoky, D. Chowdhury, ACS Appl.
Mater. Interfaces 2016, 8(32), 20625.
51] A. G. Yavuz, A. Uygun, V. R. Bhethanabotla, Carbohydr.
Polym. 2009, 75(3), 448.
52] K. Gurunathan, A. V. Murugan, R. Marimuthu, U. P. Mulik,
D. P. Amalnerkar, Mater. Chem. Phys. 1999, 61(3), 173.
53] M. A. Careem, Y. Velmurugu, S. Skaarup, K. West, J. Power
Sources 2006, 159(1), 210.
[75] G. Cardenenas, J. C. Paredes, G. Cabrea, P. Casals, J. Appl.
Polym. Sci. 2002, 86, 2742.
[76] C. Peniche-Covas, W. Arguelles-Monal, J. S. Roman, Polym.
Deg. Stab. 1993, 39(1), 21.
[77] M. M. Dutta, P. Phukan, Catal. Commun. 2018, 109, 38.
[78] L. Ackermann, R. Sandmann, W. F. Song, Org. Lett. 2011,
13(7), 1784.
[79] L. Rout, S. Jammi, T. Punniyamurthy, Org. Lett. 2007, 9(17),
3397.
[80] D. S. Raghuvanshi, A. K. Gupta, K. N. Singh, Org. Lett. 2012,
14(17), 4326.
[81] X. Liang, L. Xu, C. Li, X. Jia, Y. Wei, Tetrahedron 2019,
75(6), 721.
54] X. Yuan, X. L. Ding, C. Y. Wang, Z. F. Ma, Energy Environ. Sci.
2
013, 6(4), 1105.
55] W. Feng, X. Zhou, W. Nie, L. Chen, K. Qiu, Y. Zhang, C. He,
ACS Appl. Mater. Interfaces 2015, 7(7), 4354.
[
[
56] Z. Q. Fan, K. Q. Chen, Sci. Rep. 2014, 4(1), 1.
[82] S. Roscales, A. G. Cs ꢀa kÿ, Org. Lett. 2018, 20(6), 1667.
[83] J. C. Vantourout, R. P. Law, A. Isidro-Llobet, S. J. Atkinson,
A. J. B. Watson, J. Org. Chem. 2016, 81, 3942.
[84] L. Marzo, S. Wang, B. Konig, Org. Lett. 2017, 19, 5976.
[85] A. Biffis, F. Filippi, G. Palma, S. Lora, C. Macca, B. Corain,
J. Mol. Catal. A: Chem. 2003, 203(1–2), 213.
[86] S. M. Islam, S. Mondal, P. Mondal, A. S. Roy, K. Tuhina, N.
Salam, M. A. Mobarak, J. Organomet. Chem. 2012 Jan, 696(26),
4264.
57] M. B. Gumpu, N. Nesakumar, S. Sethuraman, U. M. Krishnan,
J. B. B. Rayappan, Sens. Actuators B: Chem. 2014, 199, 330.
58] B. S. Rathore, N. P. Chauhan, M. K. Rawal, S. C. Ameta,
R. Amet. Polym. Bull. 2019, 16, 1.
59] R. Antony, T. Arun, S. T. Manickam 2019, 129, 615.
60] A. Malaki, J. Nanosci. Nanotechnol. 2016, 12(4), 215.
61] S. M. Saadati, R. Zhiani, M. Zahedifar, S. M. Sadeghzadeh,
Appl Organometal Chem 2018, 32(12), e4560.
[
[
[
[
[
[
[
[
[
[
62] M. Zahedifar, A. Es-haghi, R. Zhiani, S. M. Sadeghzadeh, RSC
Adv. 2019, 9, 6494.
63] M. Zahedifar, B. Pouramiri, R. Razavi, Res. Chem. Intermed.
[87] J. C. Antilla, S. L. Buchwald, Org. Lett. 2001, 3(13), 2077.
[88] R. K. Borah, P. K. Raul, A. Mahanta, A. Shchukarev, J. P.
Mikkola, A. J. Thakur, Synlett 2017, 28(10), 1177.
2
020, 46, 2749.
64] D. H. Nguyen, N. Q. Tran, C. K. Nguyen, J. Biomater, Sci.
Polym. Ed. 2013, 24(14), 1636.
65] X. W. Shi, Y. M. Du, J. H. Yang, J. Appl. Polym. Sci. 2005,
How to cite this article: N. Seyedi, M. Zahedifar,
Appl Organomet Chem 2021, e6364. https://doi.org/
1
00(6), 4689.
66] L. Kunhikrishnan, R. A. Shanmugam, J. Mater, Sci.: Mater.
Electron. 2020, 31(23), 21528.
67] A. P. Martinez-Camacho, M. O. Cortez-Rocha, J. M. Ezquerra-
Brauer, A. Z. GracianoVerdugo, F. Rodriguez-Felix, M. M.
10.1002/aoc.6364