Iron oxide modified with pyridyl-triazole ligand for stabilization of gold nanoparticles: An efficient heterogeneous catalyst for A3 coupling reaction in water

Article abstract of DOI:10.1002/aoc.4454

Fe₃O₄ nanoparticles were modified with pyridyl-triazole ligand and the new magnetic solid was applied for the stabilization of very small and uniform gold nanoparticles. The resulting magnetic material, Fe₃O₄@PT

Full text of DOI:10.1002/aoc.4454

Received: 28 March 2018
DOI: 10.1002/aoc.4454
Revised: 12 April 2018
Accepted: 11 May 2018
F U L L P A P E R
Iron oxide modified with pyridyl‐triazole ligand for
stabilization of gold nanoparticles: An efficient
heterogeneous catalyst for A3 coupling reaction in water
Mohammad Gholinejad1,2
| Fatemeh Zareh1 | Carmen Najera3
1 Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), PO Box 45195‐1159, Gavazang, Zanjan 45137‐66731, Iran
2 Research Center for Basic Sciences & Modern Technologies (RBST), Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137‐66731, Iran
3 Departamento de Química Orgánica and Centro de Innovación en Química Avanzada (ORFEO‐CINQA), Universidad de Alicante, Apdo. 99, E‐03080
Alicante, Spain
Correspondence
Mohammad Gholinejad, Department of
Fe3O4 nanoparticles were modified with pyridyl‐triazole ligand and the new
Chemistry, Institute for Advanced Studies
magnetic solid was applied for the stabilization of very small and uniform gold
in Basic Sciences (IASBS), PO Box 45195‐
1159, Gavazang, Zanjan 45137‐66731,
nanoparticles. The resulting magnetic material, Fe3O4@PT@Au, was charac-
terized using various methods. These gold nanoparticles on a magnetic support
were applied as an efficient heterogeneous catalyst for the three‐component
reaction of amines, aldehydes and alkynes (A3 coupling) in neat water with
0.01 mol% Au loading. Using magnetic separation, this catalyst could be
recycled for seven consecutive runs with very small decrease in activity. Char-
acterization of the reused catalyst did not show appreciable structural
modification.
Iran.
Email: gholinejad@iasbs.ac.ir
Carmen Najera, Departamento de
Química Orgánica and Centro de
Innovación en Química Avanzada
(ORFEO‐CINQA), Universidad de
Alicante, Apdo. 99, E‐03080 Alicante,
Spain.
Email: cnajera@ua.es
Funding information
KEYWORDS
Iran National Science Foundation, Grant/
Award Number: 95844587; University of
Alicante; GeneralitatValenciana, Grant/
Award Number: PROMETEOII/2014/017;
Spanish Ministerio de Economía,
gold nanoparticles, magnetic, propargylamines, pyridyl‐triazole, water
Industria y Competitividad,
AgenciaEstatal de Investigación (AEI) and
FondoEuropeo de Desarrollo Regional
(FEDER, EU), Grant/Award Numbers:
CTQ2016‐81797‐REDC and CTQ2016‐
76782‐P; Spanish Ministerio de Economía
y Competitividad (MINECO), Grant/
Award Numbers: CTQ2014‐51912‐REDC
and CTQ2013‐43446‐P; Institute for
Advanced Studies in Basic Sciences
(IASBS) Research Council and Iran
National Science Foundation, Grant/
Award Number: 95844587
1 | INTRODUCTION
nucleophiles for the construction of carbon–carbon
bonds.[1] Traditional methods for the preparation of
Direct C─ H bond activation of alkynes is one of the most
powerful and reliable methods for converting them to
alkynylides include the use of stoichiometric amounts of
organometallic reagents such as organolithium or
Appl Organometal Chem. 2018;e4454.
wileyonlinelibrary.com/journal/aoc
© 2018 John Wiley & Sons, Ltd.
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https://doi.org/10.1002/aoc.4454

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GHOLINEJAD ET AL.
organomagnesium compounds or metal hydrides under
strict anhydrous reaction conditions. Another option are
metal‐catalysed methods for alkyne C─ H bond activa-
tion.[2–5] One of the most important applications of the
C─ H bond activation of terminal alkynes is the prepara-
tion of propargylamines by means of a three‐component
coupling reaction of amines, aldehydes and alkynes (A3
coupling).[6] Propargylamines are synthetically versatile
key molecules in the preparation of many nitrogen‐con-
taining biologically active compounds such as β‐lactams,
oxotremorine analogues, isoquinolines, oxazoles, natural
products and agrochemicals.[7–14]
Among the various solids for the preparation of heteroge-
neous catalysts, magnetic NPs having high surface area
and being easy to separate from a reaction mixture are
recognized as excellent supports for heterogeneous cata-
lyst design.[81] In recent years ligands such as phospho-
rus‐ and nitrogen‐based ligands were used for
modification and stabilization of Fe3O4 NPs. Very
recently, triazoles have been recognized as excellent
ligands for metal catalyst stabilization.[82–104] These
highly stable heterocyclic compounds can be produced
by the reaction of terminal alkynes with organic azides
catalysed by copper (I) complexes.[105–107]
In addition, propargylamines have applications as
therapeutic drug molecules in the treatment of Alzheimer's
and Parkinson's diseases.[15,16] Within the past few years,
various transition metals such as copper,[17–23] silver,[24,25]
iridium,[26] iron,[27–29] zinc,[30] indium[31] and nickel[32]
have been reported as catalysts for the preparation of
propargylamines via A3 coupling reaction under homoge-
neous or heterogeneous reaction conditions. In recent
years, increasing attention has been paid to the catalytic
performance of gold, which traditionally was considered
as a poor and inactive metal.[33–35] One of the most impor-
tant applications of gold as a catalyst was reported by Wei
and Li in A3 coupling reaction in which gold activated
alkyne C─ H bonds.[36] After reporting this method, some
other homogeneous gold catalysts were used for A3 cou-
pling reactions.[37–51] It should be noted that homogeneous
catalysts suffer from the problem of catalyst separation and
reuse, and also the problem of product contamination with
generally toxic transition metals. Recently, a few heteroge-
neous and recyclable gold catalysts have been reported for
A3 coupling reactions.[52–69] Along this line, recyclable gold
nanoparticles (NPs) of 20 nm in size have been reported for
the synthesis of propargylamines in CH3CN under efficient
reaction conditions.[70]
In continuation of our interest in heterogeneous catalysis
of A3 coupling reactions,[108,109] we envisaged that the use of
new magnetic NPs modified with a pyridyl‐triazole ligand
could contribute to the stabilization of gold NPs and be
applied as an efficient heterogeneous recyclable catalyst for
propargylamine preparation via an A3 coupling reaction.
2 | RESULTS AND DISCUSSION
The ligand, (1‐(pyridin‐2‐ylmethyl)‐1H‐1,2,3‐triazol‐4‐yl)
methanol, was prepared by reaction of 2‐(bromomethyl)
However, to date limited heterogeneous magnetic cat-
alysts have been reported for A3 coupling reactions.[71–80]
FIGURE 1 TGA curves of materials 1 and 2
SCHEME 1 Preparation of
Fe3O4@PT@Au (3)

GHOLINEJAD ET AL.
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FIGURE 2 SEM images of Fe3O4@PT@Au (3) at different magnifications
FIGURE 3 EDS mapping images of (a)
Au, (b) C, (c) Fe, (d) N, (e) O and (f) Si for
3
pyridine hydrobromide with NaN3 and propargylalcohol
catalysed by copper (I) iodide. Magnetite NPs were
prepared by a co‐precipitation method from the reaction
of FeCl3 ⋅6H2O and FeCl2 ⋅4H2O salts.[110] The thus
prepared Fe3O4 NPs were coated with a thin layer of
silica using a sol–gel process to afford core–shell
Fe3O4@SiO2 NPs (Figure S1 in supporting information).
Fourier transform infrared spectrum of Fe3O4@SiO2
showed peaks at 1097 and 1627 cm−1 related to Si─
O─ Fe and bending vibration of water adsorbed on
the surface, respectively (Figure S2 in supporting
information). Then, chloro group was introduced on

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GHOLINEJAD ET AL.
the surface of Fe3O4@SiO2 NPs by the reaction with
3‐chloropropyltrimethoxysilane.
The
resulting
Fe3O4@SiO2@Cl NPs (1) were allowed to react with
the already prepared (1‐(pyridin‐2‐ylmethyl)‐1H‐1,2,3‐
triazol‐4‐yl) methanol ligand using sodium hydride as
a base. Finally, ligand‐modified Fe3O4 NPs (2) were
treated with NaAuCl4 ⋅2H2O and NaBH4 to produce
the new magnetic supported gold NPs (Fe3O4@PT@Au;
FIGURE 6 Magnetization curves for Fe3O4, Fe3O4@SiO2@Cl (1),
Fe3O4@SiO2@ligand (2) and Fe3O4@PT@Au (3)
FIGURE 4 EDS spectrum of Fe3O4@PT@Au (3)
FIGURE 7 XRD pattern of Fe3O4@PT@Au (3)
FIGURE 5 TEM images of
Fe3O4@PT@Au (3) under different
magnifications

GHOLINEJAD ET AL.
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3). The preparation is shown in Scheme 1. Based on
atomic absorption spectroscopy (AAS) analysis, the
amount of Au in Fe3O4@PT@Au (3) was found to be
loading of organic compounds, weight losses are
observable which confirm the successful addition of the
pyridyl‐triazole ligand.
0.01 mmol g−1
.
Scanning electron microscopy (SEM) images of 3
showed a uniform morphology of these nanoparticles
(Figure 2). On the other hand, SEM mapping images
confirmed the presence of Au, C, Fe, N, O and Si
atoms, which are uniformly located in the structure
(Figure 3). In addition, the presence of various ele-
ments such as Au, N, Si, Fe and C was confirmed
using energy‐dispersive X‐ray spectroscopy (EDS)
(Figure 4).
Thermogravimetric analysis (TGA) of 1 showed a two‐
step weight loss between 25 and 800 °C (Figure 1). The
first weight loss was attributed to water and physically
adsorbed solvents and the second to the organic residues
attached to the surface of the support. The TGA curve of
ligand‐functionalized solid 2 also showed a two‐step
weight loss. As shown in Figure 1, with an increase in
Furthermore, transmission electron microscopy
(TEM) images of 3 at different magnifications showed
the presence of highly uniform and mono‐dispersed Au
NPs supported on the core–shell structure of
Fe3O4@PT@Au (Figure 5).
In order to analyse the superparamagnetic properties
of the prepared magnetic materials, magnetization curves
of Fe3O4, 1, 2 and 3 were studied. Results indicated a sig-
nificant decrease in magnetization value in
Fe3O4@SiO2@Cl compared to Fe3O4 confirming the suc-
cessful attachment of silyl and organic groups
(Figure 6). Moreover, after the addition of ligand, a small
decrease in magnetization with respect to the previous
structure was detected. However, the final Au catalyst,
Fe3O4@PT@Au, has a magnetization behaviour similar
to that Fe3O4@SiO2@ligand NPs. Also, all prepared mate-
rials showed zero coercivity and remanence without the
presence of hysteresis loops confirming the
superparamagnetic nature of the samples.
FIGURE 8 XPS spectra of Fe3O4@PT@Au (3) in (a) Fe 2p, (b)
Au 4f, (c) N 1 s and (d) C 1 s regions
TABLE 1 Optimization of reaction conditions for reaction of 4‐bromobenzaldehyde, piperidine and phenylacetylene catalysed by 3a
Yield (%)b
Temp. (°C)
Solvent
H2O
Catalyst (mol%)
Entry
86
100
92
87
30
23
14
15
50
80
80
80
80
80
80
80
0.01
0.01
0.007
0.005
0.01
0.01
0.01
0.01
1
2
3
4
5
6
7
8
H2O
H2O
H2O
1,4‐Dioxane
DMF
PhCH3
CH3CN
aReaction conditions: 4‐bromobenzaldehyde (1 mmol), piperidine (1.5 mmol), phenylacetylene (1.5 mmol) and solvent (2 ml) for 1 d.
bYields determined by 1H NMR.

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GHOLINEJAD ET AL.
TABLE 2 Reactions of aldehydes, amines and alkynes in the presence of Fe3O4@PT@Au as catalysta
Entry
R1CHO
R2 NH
Product
Yield (%)b
2
1
93
2
3
95
90
4
93
5
6
85
90
7
8
89
86
(Continues)

GHOLINEJAD ET AL.
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TABLE 2 (Continued)
Entry
R1CHO
R2 NH
Product
Yield (%)b
2
9
88
10
76
11
12
13
90
90
79
14
87
15
16
93
94
(Continues)

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GHOLINEJAD ET AL.
TABLE 2 (Continued)
Entry
R1CHO
R2 NH
Product
Yield (%)b
2
17
93
18
19
86
92
20
21
22
93
89
90
aReaction conditions: aldehyde (1 mmol), amine (1.5 mmol), alkyne (1.5 mmol), H2O (2 ml), catalyst (10 mg, 0.01 mol%), and during 1 d.
bIsolated yields after column chromatography.
X‐ray diffraction (XRD) analysis of the prepared cata-
lyst showed the presence of Fe3O4 NPs by screening
Bragg's reflections at 2θ = 30.18°, 35.5°, 43.4°, 53.5°,
57.2° and 62.8° corresponding to the (210), (311), (400),
(422), (511) and (440) planes of Fe3O4 NPs, respec-
tively.[111] Due to low loading weight of Au, peaks relat-
ing to metallic gold were weak and appeared at 2θ=
38°, 44.2°, 65° and 78° (Figure 7).[112,113]
The X‐ray photoelectron spectrum (XPS) of the Fe 2p
region shows two main binding energy peaks correspond-
ing to the electronic states of Fe 2p3/2 and Fe 2p1/2 which
can be deconvoluted into six peaks. Peaks at 710.5 and
723.7 eV are related to Fe (II) and peaks located at
713.1 and 726.1 eV are in good agreement with Fe (III)
oxidation state in the Fe3O4 phase. The small satellite
peaks at 718.2 and 732.7 eV are related to Fe3+ in the
Fe2O3 phase, suggesting that the surface of Fe3O4 was
partially oxidized to γ‐Fe2O3 (Figure 8a).[114–116] In the
case of the XPS spectrum for the Au 4f region, a doublet
peak at 83.9 and 87.5 eV corresponding to Au(0) was
observed, comprising the only Au species in the material
(Figure 8b).[108] Moreover, the N 1 s core‐level spectrum
confirms the presence of nitrogen by revealing a peak at
399.9 eV (Figure 8c).[115] The C 1 s XPS spectrum showed

GHOLINEJAD ET AL.
9 of 15
three peaks centred at 284.6, 286.4 and 288.5 eV, which
are related to C─ C or C═ C, C─ N or C─ O and C═ N
forms of carbon, respectively (Figure 8d).[117–120]
90% isolated yield (Table 2, entry 11). Furthermore,
reaction of challenging heterocyclic thiophene‐3‐
carbaldehyde with piperidine and phenylacetylene
The catalytic activity of 3 was evaluated in the three‐
component coupling reaction of amines, aldehydes and
alkynes (A3 coupling). Initial experiments using 4‐
bromobenzaldehyde, piperidine and phenylacetylene
were performed to optimize the reaction conditions. Using
catalyst 3 (0.01 mol% loading) in water at 50 °C, a yield of
86% for the reaction was obtained (Table 1, entry 1). More-
over, by using 0.01 mol% of catalyst at 80 °C, the reaction
took place quantitatively (Table 1, entry 2). By lowering
the catalyst amount to 0.007 and 0.005 mol%, lower yields
were observed (Table 1, entries 3 and 4). However, using
0.01 mol% of catalyst in other solvents such as 1,4‐dioxane,
dimethylformamide (DMF), toluene and CH3CN afforded
lower reaction yields (Table 1, entries 5–8). Therefore, we
selected water as a green and non‐toxic solvent,
0.01 mol% catalyst loading and 80 °C reaction temperature
as the most efficient and optimized reaction conditions to
study the scope of this A3 coupling.
proceeded
efficiently
and
the
corresponding
propargylamine was obtained in 90% yield (Table 2, entry
12). Reaction of 1,1′‐biphenyl‐4‐carbaldehyde with
piperidine and phenylacetylene was also studied and
results showed the formation of the corresponding prod-
uct in 79% isolated yield (Table 2, entry 13). It should
be noted that in this case the low solubility of aldehydes
in water may be responsible for a lower reactivity. Reac-
tion of 1‐octyne as aliphatic alkyne with benzaldehyde
and piperidine was also studied and the obtained results
showed the formation of corresponding product in 87%
isolated yield (Table 2, entry 14). In addition, reactions
of aldehydes with pyrrolidine or morpholine and
phenylacetylene under optimized reaction conditions
were investigated. In these cases, A3 coupling reactions
proceeded efficiently and afforded the corresponding
The three‐component reactions of structurally differ-
ent aldehydes, amines and alkynes using 0.01 mol% of
catalyst 3 were studied. Reactions of aldehydes having
electron‐withdrawing and electron‐donating groups such
as ─ Cl, ─ Me, ─ OMe and isopropyl as well as
1‐naphthaldehyde with piperidine and phenylacetylene
proceeded well and corresponding propargylamines were
obtained in high to excellent isolated yields (Table 2,
entries 1–10). In the case of the reaction of heptanal as
an
aliphatic
aldehyde
with
piperidine
and
FIGURE
9
Recycling of catalyst 3 for the reaction of
phenylacetylene the desired product was obtained in
benzaldehyde, piperidine and phenylacetylene
TABLE 3 Comparison of catalytic activity of Fe3O4@PT@Au with that of other reported Au catalysts in A3 coupling reaction of 4‐
methylbenzaldehyde, piperidine and phenylacetylene
Catalyst
Temp. (°C)
Time (h)
Au (mol%)
Yield (%)
Fe3O4@PT@Au
Au38 (SC2H4Ph)24
Au NPs[61]
80
80
24
5
0.01
0.01
10
90
84
83
75
54
83
63
88
[48]
75
12
24
7
Au@HS‐MCM[66]
80
2
IRMOF‐3‐LA‐Au[67]
NP@Au/NNN‐pincer[79]
Fe3O4@Au[80]
80
1.7
0.07
10
85
8
100
60
24
24
Au@PMO‐IL[106]
0.2

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GHOLINEJAD ET AL.
propargylamines in high to excellent yields (Table 2,
entries 15–22).
The catalytic activity of Fe3O4@PT@Au was com-
pared with that of some previously reported gold‐
catalysed A3 coupling reactions (Table 3), showing the
efficiency of the present catalyst.
reaction. Results of this study indicated that on recycling
the catalyst for seven consecutive runs a drop in reaction
yields of only 6% was observed. However, after the sev-
enth run the yields started to decrease and in the tenth
run the product was obtained in a yield of 78%
(Figure 9).
Recycling of heterogeneous noble metal‐based cata-
lysts is very important from economic and sustainable
chemistry standpoints. Therefore, we studied the
recycling of catalyst 3 for the reaction of benzaldehyde,
piperidine and phenylacetylene under the optimized
reaction conditions. For this purpose, after completion
of the reaction, the catalyst was separated using an
external magnet and reused in another run of the
TEM images of the reused catalyst after 10 runs
showed the preservation of the core–shell structure of
the catalyst and the presence of mostly uniform gold
NPs and some aggregate species (Figure 10). The TGA
curve of reused catalyst after 10 runs had a pattern very
similar to that of the fresh catalyst showing that the
catalyst structure was stable during the recycling
experiments (Figure 11). Comparison of the magnetiza-
tion curve of reused catalyst after 10 runs with that of
fresh catalyst showed very small decrease in the
magnetization value and preservation of the
superparamagnetic properties suggesting high stability
of the catalyst structure during the recycling processes
(Figure 12). Finally, XPS analysis of the reused catalyst
after 10 runs showed that the Au NPs were in metallic
form and Fe, C and N were in forms similar to those
of the fresh catalyst (Figure 13).
FIGURE 11 TGA of reused catalyst 3 after 10 runs
FIGURE 12 Magnetization curves of catalyst 3 and of the reused
FIGURE 10 TEM images of reused catalyst 3 after 10 runs
catalyst after 10 runs

GHOLINEJAD ET AL.
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FIGURE 13 XPS spectra of reused
catalyst 3 after 10 runs in (a) Fe 2p, (b) Au
4f, (c) N 1 s and (d) C 1 s regions
performed using vibrating sample magnetometry (MDK
Co., Kashan, Iran). XRD patterns were recorded using a
Philips X'Pert Pro instrument. EDS measurements were
obtained using a Carl Zeiss Sigma instrument. The con-
tent of gold in the catalyst was determined using a Varian
AAS instrument.
3 | CONCLUSIONS
The synthesized pyridyl‐triazole ligand used for modifi-
cation of Fe3O4 NPs was able to stabilize uniform gold
NPs. The characterization of these Fe3O4@PT@Au NPs
using various methods such as SEM, TEM, AAS, XRD,
XPS, TGA, vibrating sample magnetometry and SEM
mapping supports the structure of this material. This
new magnetic gold composite was applied as a catalyst
in A3 coupling reactions. Various aldehydes and amines
reacted efficiently with alkynes in water as solvent at
80 °C affording the corresponding propargylamines in
high to excellent yields. This catalyst can be easily
recovered by simple separation with a magnet and
reused for at least seven cycles without appreciate loss
of catalytic activity.
4.2 | Synthesis of Fe3O4 NPs
Magnetic (Fe3O4) nanoparticles were prepared using a
reported co‐precipitation method.[105] FeCl3 ⋅6H2O
(16 mmol, 4.32 g) and FeCl2 ⋅4H2O (8 mmol, 1.59 g) were
dissolved in deionized water (250 ml) and stirred for
10 min at room temperature. Then, aqueous ammonia
(25%, 13 ml) was added slowly over 20 min and the mix-
ture was stirred at 80 °C for 4 h under argon atmosphere.
The black magnetic precipitates were separated using an
external magnet and washed with deionized water
(3 × 10 ml) and ethanol (3 × 10 ml) and dried in a vac-
uum oven at 60 °C for 24 h.
4 | EXPERIMENTAL
4.1 | General
All chemicals were purchased from Sigma‐Aldrich, Acros
and Merck and were used without further purification.
4.3 | Synthesis of Fe3O4@SiO2 NPs
1
All H NMR and 13C NMR spectra were recorded with a
Bruker spectrometer at 400 MHz and 100 MHz, respec-
tively. Chemical shifts were recorded with reference to
tetramethylsilane as the internal standard. TGA was per-
formed at 25–800 °C in an oxygen flow using a NETZSCH
STA 409 PC/PG instrument. TEM and SEM images were
captured with JEOL JEM‐2010 and JEOL JSM 840 instru-
ments, respectively. XPS analyses were performed using a
K‐Alpha spectrometer. Magnetic measurements were
The prepared Fe3O4 NPs (1 g) were sonicated in ethanol
(200 ml) for 30 min. Then, aqueous ammonia (6 ml)
and tetraethyl orthosilicate (2 ml) were added and the
mixture was stirred for 24 h at room temperature. Then,
the reaction mixture was subjected to magnetic separa-
tion and the obtained material was washed with deion-
ized water (3 × 10 ml) and ethanol (3 × 10 ml) and
dried under vacuum at 60 °C.

12 of 15
GHOLINEJAD ET AL.
11.3 mg in 1 ml of water) was added slowly and the mix-
ture was stirred for 24 h at room temperature under
argon atmosphere. The resulting solid was separated with
a magnet, washed with water (2 × 10 ml) and ethanol
(2 × 10 ml) and dried in an oven at 60 °C.
4.4 | Synthesis of Fe3O4@SiO2@Cl (1)
Fe3O4@SiO2 NPs (1 g) were sonicated in dried toluene
(50 ml) followed by dropwise addition of)3‐chloropropyl)
trimethoxysilane (1.3 ml). The reaction mixture was
refluxed for 24 h under argon atmosphere. Then, the
resultant solids were collected using a magnet, washed
with ethanol (3 × 10 ml), rinsed and dried under vacuum
at 60 °C.
4.8 | General Procedure for Synthesis of
Propargylamines
The catalyst (10 mg, 0.01 mol%) was added to a mixture of
aldehyde (1 mmol), phenylacetylene (1.5 mmol) and
amine (1.5 mmol) in water (2 ml) and the mixture was
stirred at 80 °C for 24 h under argon atmosphere. After
the complication of reaction, the crude products were
extracted using ethyl acetate (4 × 5 ml). Further purifica-
tion was performed by column chromatography on silica
gel using hexane and ethyl acetate as eluent. All products
were known and confirmed using 1H NMR and 13C NMR
analyses.
4.5 | Synthesis of (1‐(Pyridin‐2‐ylmethyl)‐
1H‐1, 2,3‐triazol‐4‐yl)methanol
2‐Bromoethylpyridine hydrobromide (4 mmol, 1 g) and
NaN3 (6 mmol, 0.39 g) were added to stirring solution
of acetone (20 ml). In order to dissolve the NaN3, water
(2 ml) was added and the solution was refluxed for 2 h
at 60 °C. Then, Et3N (8 mmol, 1 ml), propargyl alcohol
(6 mmol, 0.3 ml) and copper (I) iodide (0.05 mmol,
9.5 mg) were added and the reaction mixture was
refluxed for 24 h at 60 °C. The acetone was evaporated
and the residue was washed with water and dichloro-
methane to extract the product to the organic phase.
Further purification was achieved using column chroma-
tography with hexane, ethyl acetate and ethanol as
eluents. The resulting product was obtained in 84% yield
and characterized using 1H NMR and 13C NMR
spectroscopies.
ACKNOWLEDGEMENTS
The authors are grateful to the Institute for Advanced
Studies in Basic Sciences (IASBS) Research Council and
Iran National Science Foundation (INSF grant no.
95844587) for support of this work. C.N. is also grateful
for financial support from the Spanish Ministerio de
Economía
CTQ2013‐43446‐P and CTQ2014‐51912‐REDC), the
Spanish Ministerio de Economía, Industria
y
Competitividad (MINECO) (projects
y
4.6 | Synthesis of Ligand‐Functionalized
Magnetic NPs (2)
Competitividad, AgenciaEstatal de Investigación (AEI)
and FondoEuropeo de Desarrollo Regional (FEDER,
EU) (projects CTQ2016‐76782‐P and CTQ2016‐81797‐
REDC), the GeneralitatValenciana (PROMETEOII/2014/
017) and the University of Alicante.
Fe3O4@SiO2@Cl (1 g) was sonicated and dispersed in dry
1,4‐dioxane (15 ml) for 30 min. In a separate reaction
batch, NaH (4 mmol, 0.1 g) was added to (1‐(pyridin‐2‐
ylmethyl)‐1H‐1,2,3‐triazol‐4‐yl) methanol (3 mmol,
0.6 g) in dry 1,4‐dioxane (15 ml) under argon and the
reaction mixture was stirred for 15 min at 25 °C. Then,
resulting mixture was added to the flask containing
Fe3O4@SiO2@Cl under argon protection and the reaction
mixture was stirred at 100 °C for 24 h. The obtained
Fe3O4@SiO2@Cl@Ligand (2) was subjected to separation
with a magnet and the obtained material was washed
ORCID
Mohammad Gholinejad
http://orcid.org/0000-0003-0209-
4509
REFERENCES
with deionized water (2
(2 × 10 ml) and dried under vacuum at 60 °C.
× 10 ml) and ethanol
[1] G. Dyker, Handbook of CH Transformations, Wiley‐VCH,
Weinheim 2005.
[2] B. J. Wakefield, Organolithium Methods in Organic Synthesis,
Academic Press, London 1988, ch. 3 32.
4.7 | Synthesis of Fe3O4@PT@Au Catalyst
(3)
[3] M. Umeno, A. Suzuki, in Handbook of Grignard Reagents, Vol.
64 (Eds.: G. S. Silvermanand, P. E. Rakita), Dekker, New
York, p. 645.
Compound 2 (1 g) was sonicated in 12 ml of H2O–
CH3OH (2:1) for 30 min at room temperature. Then, a
solution of NaAuCl4 ⋅2H2O (0.012 mmol, 4.8 mg) was
added. Then, an aqueous solution of NaBH4 (0.3 mmol,
[4] R. Bloch, Chem. Rev. 1998, 98, 1407.
[5] V. V. Kouznetsov, L. Y. V. Mendez, Synthesis 2008, 4, 491.

GHOLINEJAD ET AL.
13 of 15
[6] V. A. Peshkov, O. P. Pereshivko, E. V. Vander EyckenEycken,
[37] V. K. Y. Lo, Y. Liu, M. K. Wong, C. M. Che, Org. Lett. 2006, 8,
Chem. Soc. Rev. 2012, 41, 3790.
1529.
[7] A. Kochman, J. Skolimowski, L. Gebicka, D. Metodiewa, Pol.
J. Pharmacol. 2003, 55, 389.
[38] J. S. Yadav, B. V. S. Reddy, N. N. Yadav, M. K. Gupta, B.
Sridhar, J. Org. Chem. 2008, 73, 6857.
[8] A. Hoepping, K. M. Johnson, C. George, J. Flippen‐Anderson,
A. P. Kozikowski, J. Med. Chem. 2000, 43, 2064.
[39] V. K. Y. Lo, K. K. Y. Kung, M. K. Wong, C. M. Che,
J. Organomet. Chem. 2009, 694, 583.
[9] B. Jiang, M. Xu, Angew. Chem. Int. Ed. 2004, 43, 2543.
[40] B. T. Elie, C. Levine, I. Ubarretx‐Belandia, A. Varela‐Ramírez,
R. J. Aguilera, R. Ovalle, M. Contel, Eur. J. Inorg. Chem. 2009,
3421.
[10] J. J. Fleming, J. Du Bois, J. Am. Chem. Soc. 2006, 128, 3926.
[11] A. S. K. Hashmi, P. Haufe, C. Schmid, A. R. Nass, W. Frey,
[41] Q. Zhang, M. Cheng, X. Hu, B. G. Li, J. X. Ji, J. Am. Chem.
Soc. 2010, 132, 7256.
Chem. A Eur. J. 2006, 12, 5376.
[12] S. K. Hashmi, T. M. Frost, J. W. Bats, J. Am. Chem. Soc. 2000,
122, 11553.
[42] Y. Suzuki, S. Naoe, S. Oishi, N. Fujii, H. Ohno, Org. Lett. 2012,
14, 326.
[13] A. S. K. Hashmi, J. P. Weyrauch, W. Frey, J. W. Bats, Org. Lett.
2004, 6, 4391.
[43] J. Li, L. Liu, D. Ding, J. Sun, Y. Ji, J. Dong, Org. Lett. 2013, 15,
2884.
[14] S. Bay, T. Baumeister, A. S. K. Hashmi, T. Röder, Org. Process
Res. Dev. 2016, 20, 1297.
[44] B. J. Borah, S. J. Borah, D. K. Dutta, J. Nanosci. Nanotechnol.
2013, 13, 5080.
[15] M. Naoi, W. Maruyama, M. Shamoto‐Nagai, H. Yi, Y. Akao,
M. Tanaka, Mol. Neurobiol. 2005, 31, 81.
[45] V. Srinivas, M. Koketsu, Tetrahedron 2013, 69, 8025.
[16] J. J. Chen, D. M. Swope, K. Dashtipour, Clin. Ther. 2007, 29,
[46] G. A. Price, A. K. Brisdon, K. R. Flower, R. G. Pritchard, P.
1825.
Quayle, Tetrahedron Lett. 2014, 55, 151.
[17] H. Naeimi, M. Moradian, Appl. Catal. A 2013, 467, 400.
[47] J. Li, H. Wang, J. Sun, Y. Yang, L. Liu, Org. Biomol. Chem.
2014, 12, 2523.
[18] J. R. Cammarata, R. Rivera, F. Fuentes, Y. Otero, E. Ocando‐
Mavárez, A. Arce, J. M. Garcia, Tetrahedron Lett. 2017, 58,
4078.
[48] Q. Li, A. Das, S. Wang, Y. Chen, R. Jin, Chem. Commun. 2016,
52, 14298.
[19] J. Rosales, J. M. Garcia, E. Ávila, T. González, D. S. Coll, E.
[49] E. Belmonte, M. J. Iglesias, H. Hajjouji, L. Roces, S. García‐
Granda, P. Villuendas, E. P. Urriolabeitia, F. Lopez Ortiz,
Organometallics 2017, 36, 1962.
Ocando‐Mavárez, Inorg. Chim. Acta 2017, 467, 155.
[20] V. S. Kashid, M. S. Balakrishna, Cat. Com. 2018, 103, 78.
[21] Y. J. Choi, H. Y. Jang, Eur. J. Org. Chem. 2016, 18, 3047.
[50] A. Sharma, D. Mejía, A. Regnaud, N. Uhlig, C. J. Li, D.
Maysinger, A. Kakkar, ACS Macro Lett. 2014, 3, 1079.
[22] A. Bukowska, W. Bukowski, K. Bester, K. Hus, Appl.
Organomet. Chem. 2017, 31, 3847.
[51] J. Li, M. Rudolph, F. Rominger, J. Xie, A. S. K. Hashmi, Adv.
Synth. Catal. 2016, 358, 207.
[23] S. Frindy, A. El Kadib, M. Lahcini, A. Primo, H. García, Cat.
Sci. Technol. 2016, 6, 4306.
[52] M. L. Kantam, B. V. Prakash, C. R. V. Reddy, B. Sreedhar,
Synlett 2005, (15), 2329.
[24] C. Wei, Z. Li, C. J. Li, Org. Lett. 2003, 5, 4473.
[25] S. J. Borah, D. K. Das, Catal. Lett. 2016, 146, 656.
[53] X. Zhang, A. Corma, Angew. Chem. Int. Ed. 2008, 47, 4358.
[54] K. K. R. Datta, B. V. S. Reddy, K. Ariga, A. Vinu, Angew.
Chem. Int. Ed. 2010, 49, 5961.
[26] S. Sakaguchi, T. Kubo, Y. Ishii, Angew. Chem. Int. Ed. 2001,
113, 2602.
[55] L. Abahmane, J. M. Köhler, G. A. Groß, Chem. A Eur. J. 2011,
17, 3005.
[27] T. Zeng, W. W. Chen, C. M. Cirtiu, A. Moores, G. Song, C. J.
Li, Green Chem. 2010, 12, 570.
[56] G. Villaverde, A. Corma, M. Iglesias, F. Sánchez, ACS Catal.
2012, 2, 399.
[28] J. Gao, Q. W. Song, L. N. He, Z. Z. Yang, X. Y. Dou, Chem.
Commun. 2012, 48, 2024.
[29] R. K. Sharma, S. Sharma, G. Gaba, RSC Adv. 2014, 4, 49198.
[57] L. F. Bobadilla, T. Blasco, J. A. Odriozola, Phys. Chem. Chem.
Phys. 2013, 15, 16927.
[30] M. Periasamy, P. O. Reddy, A. Edukondalu, M. Dalai, L. M.
Alakonda, B. Udaykumar, Eur. J. Org. Chem. 2014, 6067.
[58] L. Lili, Z. Xin, R. Shumin, Y. Ying, D. Xiaoping, G. Jinsen, X.
Chunming, H. Jing, RSC Adv. 2014, 4, 13093.
[31] Y. Zhang, P. Li, M. Wang, L. Wang, J. Org. Chem. 2009, 74,
4364.
[59] S. K. Movahed, N. F. Lehi, M. Dabiri, RSC Adv. 2014, 4, 42155.
[32] S. Samai, G. C. Nandi, M. S. Singh, Tetrahedron Lett. 2010, 51,
[60] A. Berrichi, R. Bachir, M. Benabdallah, N. Choukchou‐
Braham, Tetrahedron Lett. 2015, 56, 1302.
5555.
[33] M. Haruta, Gold Bull. 2004, 37, 27.
[61] M. Nasrollahzadeh, S. M. Sajadi, RSC Adv. 2015, 5, 46240.
[62] S. Shabbir, Y. Lee, H. Rhee, J. Catal. 2015, 322, 104.
[34] A. S. K. Hashmi, Chem. Rev. 2007, 107, 3180.
[35] D. Pflästerera, A. S. K. Hashmi, Chem. Soc. Rev. 2016, 45, 1331.
[36] C. Wei, C. J. Li, J. Am. Chem. Soc. 2003, 125, 9584.
[63] L. Liu, X. Tai, N. Zhang, Q. Meng, C. Xin, React. Kinet., Mech.
Catal. 2016, 119, 335.

14 of 15
GHOLINEJAD ET AL.
[64] L. Lili, T. Xishi1, Y. Guanglin, G. Huanmei, M. Qingguo,
[91] S. Su, G. Yue, D. Huang, G. Yang, X. Lai, P. Zhao, RSC Adv.
2015, 5, 44018.
Chem. Res. Chin. Univ. 2016, 32, 443.
[92] M. Massaro, S. Riela, G. Cavallaro, C. G. Colletti, S. Milioto, R.
[65] Y. Adachi, H. Kawasaki, T. Nagata, Y. Obora, Chem. Lett.
2016, 45, 1457.
Noto, F. Parisi, G. Lazzara, J. Mol. Catal. A 2015, 408, 12.
[93] S. E. Motika, Q. Wang, X. Ye, X. Shi, Org. Lett. 2015, 17, 290.
[66] A. Feiz, A. Bazgir, Cat. Com. 2016, 73, 88.
[94] Y. Yang, A. Qin, K. Zhao, D. Wang, X. Shi, Adv. Synth. Catal.
2016, 358, 1433.
[67] L. Liu, X. Tai, X. Zhou, C. Xin, Y. Yan, Sci. Rep. 2017, 7, 12709.
[68] X. B. Zhao, W. Ha, K. Jiang, J. Chen, J. L. Yang, Y. P. Shi,
[95] J. R. Wright, J. D. Crowley, N. T. Lucas, Chem. Commun.
2016, 52, 12976.
Green Chem. 2017, 19, 1399.
[69] L. Liu, X. Tai, X. Zhou, Materials 2017, 10, 99.
[96] S. Kumar, F. Saleem, A. K. Singh, Dalton Trans. 2016, 45,
[70] M. Kidwai, V. Bansal, A. Kumar, S. Mozumdar, Green Chem.
2007, 9, 742.
11445.
[97] M. Kongkaew, K. Sitthisuwannakul, V. Nakarajouyphon, S.
Pornsuwan, P. Kongsaereea, P. Sangtrirutnugul, Dalton Trans.
2016, 45, 16810.
[71] A. T. Nguyen, L. T. Pham, N. T. S. Phan, T. Truong, Cat. Sci.
Technol. 2014, 4, 4281.
[72] F. Nemati, A. Elhampour, H. Farrokhi, M. BagheriNatanzi,
[98] C. Wang, L. Salmon, Q. Li, M. E. Igartua, S. Moya, R. Ciganda,
Cat. Com. 2015, 66, 15.
J. Ruiz, D. Astruc, Inorg. Chem. 2016, 55, 6776.
[73] F. M. Moghaddam, S. E. Ayati, S. H. Hosseini, A. Pourjavadi,
[99] A. R. Hajipour, P. Abolfathi, RSC Adv. 2016, 6, 110622.
RSC Adv. 2015, 5, 34502.
[100] A. Scrivanti, V. Beghetto, M. M. Alam, S. Paganelli, P. Canton,
[74] A. Elhampour, M. Malmir, E. Kowsari, F. Boorboorajdari, F.
M. Bertoldini, E. Amadio, Inorg. Chim. Acta 2017, 455, 613.
Nemati, RSC Adv. 2016, 6, 96623.
[101] N. Sun, X. Zhang, L. Jin, B. Hu, Z. Shen, X. Hu, Cat. Com.
2017, 101, 5.
[75] Z. Zarei, B. Akhlaghinia, RSC Adv. 2016, 6, 106473.
[76] A. M. Munshi, V. Agarwal, D. Ho, C. L. Raston, M. Saunders,
[102] H. V. Ching, X. Wang, M. He, N. PerujoHolland, R. Guillot, C.
Slim, S. Griveau, H. C. Bertrand, C. Policar, F. Bedioui, M.
Fontecave, Inorg. Chem. 2017, 56, 2966.
N. M. Smith, K. S. Iyer, Cryst. Growth Des. 2016, 16, 4773.
[77] A. Elhampour, F. Nemati, M. M. Heravi, Monatsh. Chem.
2017, 148, 1793.
[103] A. Saad, C. Vard, M. Abderrabba, M. M. Chehimi, Langmuir
2017, 33, 7137.
[78] A. Moaddeli, M. Abdollahi‐Alibeik, J. Porous Mater. 2018, 25,
147.
[104] R. Cai, X. Ye, Q. Sun, Q. He, Y. He, S. Ma, X. Shi, ACS Catal.
2017, 7, 1087.
[79] N. Zohreh, S. H. Hosseini, M. Jahani, M. S. Xaba, R.
[105] C. W. Tornøe, C. Christensen, M. Meldal, J. Org. Chem. 2002,
67, 3057.
Meijboom, J. Catal. 2017, 356, 255.
[80] A. M. Munshi, M. Shi, S. P. Thomas, M. Saunders, M. A.
Spackman, K. S. Iyer, N. M. Smith, Dalton Trans. 2017, 46,
5133.
[106] V. V. Rostovtsev, L. G. Green, V. V. Fokin, K. B. Sharpless,
Angew. Chem. Int. Ed. 2002, 41, 2596.
[107] L. Liang, D. Astruc, Coord. Chem. Rev. 2011, 255, 2933.
[81] B. Karimi, F. Mansouri, H. M. Mirzaei, ChemCatChem 2015,
7, 1736.
[108] B. Karimi, M. Gholinejad, M. Khorasani, Chem. Commun.
2012, 48, 8961.
[82] C. Shen, P. F. Zhang, X. Z. Chen, Helv. Chim. Acta 2010, 93,
2433.
[109] M. Gholinejad, F. Saadati, S. Shaybanizadeh, B. Pullithadathil,
RSC Adv. 2016, 6, 4983.
[83] T. C. Johnson, W. G. Totty, M. Wills, Org. Lett. 2012, 14, 5230.
[110] R. Massart, IEEE Trans. Magn. 1981, 17, 1247.
[84] D. Wang, D. Denux, J. Ruiz, D. Astruc, Adv. Synth. Catal.
2013, 355, 129.
[111] M. Gholinejad, J. Ahmadi, C. Najera, M. Seyedhamzeh, F.
Zareh, M. Kompany‐Zareh, ChemCatChem 2017, 9, 1442.
[85] E. Amadio, A. Scrivanti, M. Bortoluzzi, M. Bertoldini, V.
Beghetto, U. Matteoli, G. Chessa, Inorg. Chim. Acta 2013,
405, 188.
[112] S. S. Shankar, A. Ahmad, R. Pasricha, M. Sastry, J. Mater.
Chem. 2003, 13, 1822.
[113] M. Gholinejad, J. Ahmadi, C. Nájera, Chem. Select 2016, 3, 384.
[86] E. Amadio, A. Scrivanti, V. Beghetto, M. Bertoldini, M. M.
Alam, U. Matteoli, RSC Adv. 2013, 3, 21636.
[114] W. Wang, B. Tang, B. Ju, Z. Gao, J. Xiu, S. Zhang, J. Mater.
Chem. A 2017, 5, 958.
[87] X. You, Z. Wei, Transition Met. Chem. 2014, 39, 675.
[115] G. Li, R. Li, W. Zhou, Nano‐Micro Lett. 2017, 9, 46.
[88] F. Saleem, G. K. Rao, A. Kumar, S. Kumar, M. P. Singh, A. K.
Singh, RSC Adv. 2014, 4, 56102.
[116] X. Wang, Y. Liu, H. Han, Y. Zhao, W. Mad, H. Sun, Sustain.
Energy Fuels 2017, 1, 915.
[89] N. Li, M. Echeverría, S. Moya, J. Ruiz, D. Astruc, Inorg. Chem.
2014, 53, 6954.
[117] V. Leon, M. Quintana, M. A. Herrero, J. L. G. Fierro, A. de la
Hoz, M. Prato, E. Vazquez, Chem. Commun. 2011, 47, 10936.
[90] A. A. Kirilchuk, A. A. Yurchenko, Y. G. Vlasenko, A. N.
Kostyuk, A. B. Rozhenko, Chem. Heterocycl. Compd. 2015,
50, 1559.
[118] X. Chen, J. Zhang, S. Ma, H. Hu, Z. Zhou, Acta Metall. Sin.
Engl. 2014, 27, 31.

GHOLINEJAD ET AL.
15 of 15
[119] Z. Yang, Y. Dai, S. Wang, H. Cheng, J. Yu, RSC Adv. 2015, 5,
78017.
How to cite this article: Gholinejad M, Zareh F,
Najera C. Iron oxide modified with pyridyl‐triazole
ligand for stabilization of gold nanoparticles: An
efficient heterogeneous catalyst for A3 coupling
reaction in water. Appl Organometal Chem. 2018;
e4454. https://doi.org/10.1002/aoc.4454
[120] Z. J. Jiang, Z. Jiang, Sci. Rep. 2016, 6, 27081.
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