Nano-Fe3O4@TiO2/Cu2O Core-shell Composite: A Convenient Magnetic Separable Catalyst for A3 and KA2 Coupling

Article abstract of DOI:10.1002/jccs.201500519

An eco-efficient one-pot three component reaction between different aldehydes or ketones with alkynes and amines for the synthesis of propargylamines was performed using Fe₃O₄@TiO₂/Cu₂O as a nano-magnetic composite under solvent free condition. The catalyst showed remarkable catalytic activity by decreasing the time of the reaction in comparison of other reported magnetic catalysts. In addition, the Fe₃O₄@TiO₂/Cu₂O can be easily recycled and reutilized for five times without apparent loss of catalytic activity.

Full text of DOI:10.1002/jccs.201500519

JOURNAL OF THE CHINESE
CHEMICAL SOCIETY
Article
Nano-Fe3O4@TiO2/Cu2O Core-shell Composite: A Convenient Magnetic Separable
Catalyst for A3 and KA2 Coupling
Ali Elhampour and Firouzeh Nemati*
Department of Chemistry, Semnan University, Semnan, Iran
(Received: Dec. 17, 2015; Accepted: Jun. 3, 2016; Published Online: ???; DOI: 10.1002/jccs.201500519)
An eco-efficient one-pot three component reaction between different aldehydes or ketones with alkynes
and amines for the synthesis of propargylamines was performed using Fe3O4@TiO2/Cu2O as a nano-mag-
netic composite under solvent free condition. The catalyst showed remarkable catalytic activity by de-
creasing the time of the reaction in comparison of other reported magnetic catalysts. In addition, the
Fe3O4@TiO2/Cu2O can be easily recycled and reutilized for five times without apparent loss of catalytic
activity.
Keywords: Core-shell composite; Nano-magnetic; Propargylamine
INTRODUCTION
In recent years, multi component reactions (MCRs)
the copper particles cannot easily remove from the reaction
mixture, which may increase the cost of industrial applica-
tions. Therefore, there is the need to develop an efficient
and well defined heterogeneous copper catalyst for A3 cou-
pling still remains an interesting and demanding goal. Re-
cently, one of the important aim in the organic chemical re-
search is the synthesis of new catalysis or reagents, which
are less expensive, selective, recyclable and environmen-
tally more benign and their application in specific reac-
tions.10 In this regard, nanostructure particles are suitable
candidates for heterogeneous catalyst in green organic syn-
thesis. Nano catalysts are isolated and recovered through
filtration or centrifugation methods, whereas the inconve-
nience and inefficiency of these tedious methods caused by
the nano size of the catalyst particles inhibit the sustain-
ability and economics of the nano-catalytic strategy.11 In
order to overcome these problems, magnetite nano-parti-
cles (Fe3O4) have increasingly attracted interest in the past
few days, because they can be easily recovered from the re-
action mixture using an external magnet. In addition, they
posses specific features and are adaptable to large-scale
production.
have gained eminence as an efficient access to assemble
molecular complexity with attractive biological features
through the simple and readily available starting materials
in one-pot operation.1 Among them, propargylamines have
emerged as an important building blocks and useful skele-
tons for preparation of many nitrogen containing biological
active compounds, such as b-lactams, oxotremorine ana-
logues, polyfunctional amino derivatives and therapeutic
drugs. Additionally, the propargylamines has attracted
much attention due to the fact that they have widespread
applications as key intermediates in the construction of a
variety of nitrogenous biologically active compounds.2
Due to the wide range application of propargylamine
derivatives in organic synthesis, there is an imperative need
to develop methodology for the synthesis of these com-
pounds. The most common technique to access these com-
pounds involves transition-metal-catalyzed three-compo-
nent coupling of alkyne-aldehyde-amine (A3 coupling) or
coupling of ketones, alkynes, amines (KA2 coupling).3
There has been an ongoing interest to develop homo-
geneous and heterogeneous metal catalysis such as gold,
silver, iridium and copper in A3 coupling reaction.4-7
Among them, Cu2O have great potential catalyst activity
for synthesis of propargylamines. Because, it is a cheaper,
more abundant material and it provide good reactivity for
the reaction.8 However, heterogeneous or homogeneous
catalysts involving Cu(I) species frequently suffer from
some problems because of instability of Cu(I).9 In addition,
An inherent disadvantage of naked MNPs is their sen-
sitivity to oxidation and rapid aggregation.12 Thus, to solve
this problem, MNPs are normally coating using suitable
stabilizing materials to prevent irreversible aggregation,
retain their nanoscale properties and finely dispersed active
sites. Many materials have been explored to be as outer
shells of iron oxides.13 Among the common supports that
used for coating of ferromagnetic materials, titanium diox-
* Corresponding author. Tel: +98 9122057819, +98(23)31533171; Email: Fnemati@semnan.ac.ir, fnemati_1350@yahoo.com
Supporting information for this article is available on the www under http://dx.doi.org/10.1002/jccs.201500519
J. Chin. Chem. Soc. 2016, 63, 000-000
© 2016 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
1

Article
Elhampour and Nemati
ide has attracted great attention due to its unique proper-
ties.14 It widely used as a multifunctional ceramic material
due to its excellent stability, great accessibility and moder-
ate cost. Furthermore, the inclusion of Fe3O4 core into TiO2
nano-spheres makes them easy to be recovered with a mag-
netic field and convenient recycling.
Fe3O4@TiO2/Cu2O show two major loss regions. The first
can be attributed to desorption of adsorbed water and sol-
vent molecules. The second weight loss, that was starting
around 150 °C, corresponds to the starting of TiO2 and
Cu2O crystallization. The other event after 250 °C was at-
tributed to the loss of structural water.19 As we expected,
Fe3O4 and Cu2O will transfer to Fe2O3 and CuO in higher
temperature. Therefore, no obvious weight loss could be
observed with increase of temperature (Figure 2). In addi-
tion from TG analysis, the mass ratio of the Fe3O4 in the
core-shell magnetic composite is about 75%, that enough
for easily collection of it from the reaction solution using
an external magnet. The results, also suggest that the
Fe3O4@TiO2/Cu2O composite might possess good stability
and could be safely used in organic reaction in range of
100-200 °C.
In our continuing efforts towards the development of
efficient and environmentally benign synthetic methodo-
logy,15 very recently, we have reported on the preparation
of a new core-shell nano magnetic composite consisting in
Cu2O micro crystals dispersed on TiO2 coated magnetite,16
which demonstrated to be a very efficient and recyclable
catalyst for the regioselective synthesis of 1,2,3-triazoles.
As a part of our continued interest in application of nano-
magnetic catalysts in organic transformations17 and to de-
velop remarkable performance of this new Cu2O based
nano magnetic catalyst, herein, we decided to examine its
catalytic efficiency in the coupling of carbonyl com-
pounds, alkynes and amine for synthesis of propargy-
lamines in solvent-free condition.
Catalytic performance of Fe3O4@TiO2/Cu2O magnetic
composite
After the successful preparation and characterization
of the Fe3O4@TiO2/Cu2O composite, the catalytic activity
of the magnetic composite was tested by the model reaction
of benzaldehyde, phenyl acetylene and piperidine to obtain
RESULTS AND DISCUSSION
Catalyst preparation and characterization
The nano-Fe3O4@TiO2/Cu2O core-shell magnetic
composite was prepared as previously reported by us.16
Magnetic Fe3O4 nanoparticles are first synthesized via con-
ventional co-precipitation method without using capping
agent or surfactant. Then, the magnetic nanoparticles co-
ated with layer of amorphous TiO2 under sol-gel method.
Lastly the Fe3O4@TiO2 core-shell nano-particles deco-
rated with Cu2O micro crystals by reduction of CuCl2 in al-
kaline media in the presence of hydroxylamine hydrochlo-
ride. The X-ray diffraction analysis of nano-Fe3O4@TiO2/
Cu2O with ratio of Fe3O4@TiO2:Cu2O 80:20 confirmed
formation of catalyst by screening Bragg’s reflections re-
lated to Fe3O4@TiO2 nano core-shell particles in 2q = 30.1,
35.5, 43.2, 53.4, 57.1, 62.7 and broad diffraction peak ap-
peared at 2q = 20-30 nm and Bragg’s reflections related to
Cu2O in 2q = 29.5, 36.7, 42.5, 52.7, 61.6, 73.7. (Figure 1).18
The VSM results show that the saturation magnetization of
Fe3O4 nanoparticles was reduced after being coated with
TiO2 layer and further decreased after being composed
with Cu2O micro crystals. The Fe3O4@TiO2/Cu2O has a
saturation magnetization of 24.11 emu/g, which is ade-
quate enough for efficient and rapid separation of the
catalyst from the reaction mixture.
Fig. 1. XRD analysis of nano-Fe3O4@TiO2/Cu2O.
The thermogravimetric analyses for Fe3O4@TiO2 and
Fig. 2. TGA analysis.
2
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JOURNAL OF THE CHINESE
CHEMICAL SOCIETY
A Nano-magnetic Composite for A3 and KA2 Coupling Reaction
1-(1,3-diphenylprop-2-ynyl)piperidine 5a using 0.01 g
magnetic composite in solvent free condition at 100 °C
(Scheme 1).
ture or catalyst decreased the yield of the reaction. After
that, we analyzed the influence of the molar ratio of sub-
strates on the reaction yield. We observed that the most
suitable mole ratio of benzaldehyde/phenylacetylene/
amine was 1:1.2:1.1 that affected positively the yield of the
product. Accordingly, best conditions were found when the
reaction performed under solvent-free condition in the
presence of 10 mg of magnetic composite at 100 °C.
The model reaction
Scheme 1
So, with the optimized reaction condition in hand, the
generality of reaction was studied with arylacetylenes, sec-
ondary aliphatic amines and aromatic aldehydes bearing
electron-withdrawing and donating substituents as shown
in Table 2. In order to study the generality of the Fe3O4@
TiO2/Cu2O magnetic composite, we further investigated
the reaction of some aliphatic aldehydes in the reaction.
The optimum condition for this one-pot multi-component
reaction was aldehyde 1.1 mmol, secondary amine 1.1
mmol and alkyne 1.2 mmol in the presence of 10 mg mag-
netic composite under solvent free reaction at 100 °C.
In general, both aromatic aldehydes bearing elec-
tron-donating substituents as well as electron-withdrawing
groups and aliphatic aldehydes provided the desired pro-
ducts in good to excellent yields (65-96%) within 40-90
min of reaction time. The yield was only modestly reduced
upon using aliphatic aldehydes instead of aromatic ones.
However, conjugated aliphatic aldehyde such as cinnamal-
dehyde produced corresponding product in low yield. It is
worth mentioning that heteroaryl aldehydes and strically
bulky aldehydes were also investigated (Table 2, entries 7,
9). As shown in Tables 2, the yield was dependent upon the
The reaction of benzaldehyde (1 mmol), phenyl-
acetylene (1.5 mmol) and piperidine (1.2 mmol) was se-
lected as a template reaction in various solvents, tempera-
tures and loading of magnetic composite. The results for
the optimization of the reaction conditions are summarized
in Table 1. Interestingly, the reaction performed under the
solvent-free condition at 100 °C in high yield of product
(Table 1, entry 5). We carried out the model reaction in the
presence of Fe3O4@TiO2 as a catalyst under solvent-free
condition at 100 °C and only the poor yield of 5a was
formed after 1 h (Table 1, entry 2).20 Moreover, the reaction
did not occurred in the absence of the catalyst after pro-
longed reaction time (Table 1, entry 1). The differences in
activity of magnetic core-shell in the presence and in the
absence of Cu2O proved that the active role of Cu2O in A3
coupling reaction. A higher reaction temperature or the cat-
alyst amount does not make an obvious difference in the
yield of product (Table 1). But, a lower amount of tempera-
Table 1. Comparison of the results obtained for the synthesis of A3 coupling under
different reaction conditionsa
Yieldb (%) Time (min)
Condition
Catalyst (g)
Entry
Trace
30
180
60
60
60
60
60
70
50
60
90
90
90
60
Solvent Free/100 °C
Solvent Free/100 °C
None
1
2
Fe3O4@TiO2 (0.01)
45
Solvent Free/100 °C Fe3O4@TiO2/Cu2O (0.005)
3
85
Solvent Free/90 °C
Solvent Free/100 °C
Solvent Free/110 °C
Solvent Free/100 °C
Solvent Free/100 °C
Toluene/90 °C
Fe3O4@TiO2/Cu2O (0.01)
Fe3O4@TiO2/Cu2O (0.01)
Fe3O4@TiO2/Cu2O (0.01)
Fe3O4@TiO2/Cu2O (0.01)
Fe3O4@TiO2/Cu2O (0.01)
Fe3O4@TiO2/Cu2O (0.01)
Fe3O4@TiO2/Cu2O (0.01)
Fe3O4@TiO2/Cu2O (0.01)
Fe3O4@TiO2/Cu2O (0.01)
4
95
5
95
6
95
7
77
8
93
9
Trace
60
Water/reflux
10c
11c
12c
Ethanol/reflux
Trace
95
DMSO/90 °C
Solvent Free/90 °C
Fe3O4@TiO2/Cu2O (0.015) 13c
a Reaction conditions: benzaldehyde (1 mmol), piperidine (1.1 mmol),
phenylacetylene (1.2 mmol). b Isolated yield. c solvent (2 mL).
J. Chin. Chem. Soc. 2016, 63, 000-000
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Article
Elhampour and Nemati
nature of amines. Therefore, cyclic amines such as mor-
pholine and pyrrolidine gave similar results to those ob-
tained with piperidine, whereas diethylamine rendered the
corresponding product in modest yield. However, the reac-
tion failed to occur with aromatic amines. It is pertinent to
note that the desired products were obtained with phenyl-
acetylenes bearing electron-donating or electron-with-
drawing groups. Unfortunately, aliphatic alkynes react
with low yield.
Further, in order to envisage the scope of the catalytic
activity of Fe3O4@TiO2/Cu2O magnetic composite toward
the synthesis of propargylamines (A3 coupling), the opti-
Table 2. Synthesis of three-component reaction of derivatives aldehyde, secondary-amines and
terminal alkynes catalyzed by Fe3O4@TiO2/Cu2Oa
Yieldb Time
Product
R4
R3
R2
R1
Entry
(%)
(min)
95
92
88
90
93
88
93
91
94
85
80
96
89
88
87
88
81
65
92
83
94
85
76
91
82
87
84
66
84
91
88
82
71
55
60
60
55
65
65
60
70
55
80
90
60
75
75
65
75
65
60
40
40
40
40
45
45
45
45
45
45
45
45
45
45
45
5a
5b
5c
5d
5e
5f
4a: C6H5
3a: -(CH2)5-
1a: C6H5
1
2
4a
3a
1b: p-Cl-C6H4
4a
3a
1c: o-Cl-C6H4
3
4a
3a
1d: p-Br-C6H4
4
4a
3a
1e: p-Me-C6H4
5
4a
3a
1f: p-MeO-C6H4
6
5g
5h
5i
4a
3a
1g: o-Thienyl
7
4a
3a
1h: p-OHCC6H4
8
4a
3a
1i: o-Naphthyl
9
5j
4b: p-CH3-C6H4
3a
1a
10
11
12
13
14
15
16
17
18
19c
20c
21c
22c
23c
24
25
26
27
28
29
30
31
32
33
5k
5l
4c: p-F-C6H4
3a
1a
4a
4a
4a
4a
4b
4a
4a
4a
4b
4a
4a
4a
4a
4b
4a
4a
4a
4c
4a
4a
4a
4a
3b: -(CH2)2-O-(CH2)2-
1a
5m
5n
5o
5p
5q
5r
3b
1b
3b
1e
3b
1d
3b
1a
3c: -(CH2)4-
1a
C2H5
3d: C2H5
3a
1a
6a
6b
6c
6d
6e
6f
2a: H
3a
2a
3b
2a
3c
2a
3d
2a
3a
2b: C6H11
6g
6h
6i
3b
2b
3b
2b
3c
2b
6j
3d
2b
6k
6l
3a
2b
3a
2c: -(CH2)2-Me
6m
6n
6o
3b
2c
2c
2c
3c
3d
a Reaction conditions: aliphatic aldehyde (1.1 mmol) or arylaldehydes (1 mmol), amines (1.1 mmol),
alkynes (1.2 mmol), Fe3O4@TiO2/Cu2O (0.010 g) under solvent-free conditions at 100 °C. b Isolated
yield. c Aqueous formaldehyde (37%, 0.4 mL).
4
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A Nano-magnetic Composite for A3 and KA2 Coupling Reaction
mized reaction conditions were tested for the three-compo-
nent coupling of ketones, secondary amines and aryl-
acetylenes (KA2 coupling) (Table 3). Regardless, in A3
coupling reaction, the C=N electrophiles have been re-
stricted to aldimines generated in situ. Ketoimines are gen-
erally considered to be less reactive towards nucleophilic
additions than aldimines, owing to the steric hindrance and
electronic effects. Therefore, the utilization of ketoimines
generated in situ in the direct alkyne addition reaction still
remains a significant challenge for chemists.21 Up to date,
only few methods have been developed in this field and
therefore, this restriction necessitates the development of
new catalyst for KA2 coupling reaction.22
fore, the activity of Fe3O4@TiO2/Cu2O magnetic compos-
ite was studied in the one-pot synthesis of diphenylprop-
2-ynyl piperidine 5a under the optimized condition.
For this mean, after completion of the reaction, the re-
action mixture diluted with ethylacetate and the catalyst
was recovered using a magnet. The recovered catalyst thor-
oughly washed and dried and then used again under the
same conditions. With the reuse cycle increasing the yield
has no obvious decrease. Even after using 5 times, the yield
of target product decreased by 10% and it suggested that
the Fe3O4@TiO2/Cu2O magnetic composite has high sta-
bility and recyclability (Figure 3).
The reaction condition for KA2 coupling reaction was
optimized using, cyclohexanone, piperidine and phenyl-
acetylene. When a (1.5:1:1.5) mixture of the respective
compounds with 0.01 g magnetic composite was stirred un-
der solvent-free condition at 100 °C, the desired quaternary
carbon-containing propargylamine 8d could be isolated in
85% yield. As shown in Table 3, the scope of the KA2 cou-
pling reaction was evaluated using cyclic ketones (cyclo-
hexanone and cyclopentanone), secondary amines and al-
kynes, applying the optimal condition, and exhibited good
reactivity (Table 3). It is worth nothing that, aromatic ke-
tones gave none of the desired product, which is in accor-
dance with earlier studies.22,23
EXPERIMENTAL
Preparation of composite
Preparation of Fe3O4: The nano-Fe3O4 particles were pre-
The recyclability of catalyst is an important benefit
that makes it useful for commercial applications. There-
Fig. 3. The reusability of catalyst.
Table 3. Synthesis of the three-component reaction of aliphatic ketones, secondary-
amines and terminal alkynes catalyzed by Fe3O4@TiO2/Cu2Oa
Yieldb Time
Product
R5
R3, R4
R1, R2
Entry
(%)
(min)
84
81
82
85
82
85
82
89
82
140
140
140
150
180
150
180
150
160
8a
8b
8c
8d
8e
8f
4a: C6H5
3a: -(CH2)5-
7a: -(CH2)4-
1
2
3
4
5
6
7
8
9
4a
3b: -(CH2)2-O-(CH2)2-
7a
4a
3c: -(CH2)4-
7a
4a
3a
3a
3b
3b
3c
3b
7b: -(CH2)5-
4b: p-CH3-C6H4
7b
7b
7b
7b
7b
4a
8g
8h
8i
4b
4a
4c: p-F-C6H4
c Reaction conditions: ketones (1.5 mmol), amines (1 mmol), alkynes (1.5 mmol),
Fe3O4@TiO2/Cu2O (0.010 g) under solvent-free conditions at 100 °C. d Isolated yield.
J. Chin. Chem. Soc. 2016, 63, 000-000
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Article
Elhampour and Nemati
pared in accordance with our earlier report.17b
ACKNOWLEDGEMENTS
Preparation of nano-Fe3O4@TiO2: Nano-Fe3O4@TiO2
was synthesized according to a previously reported method,24
subjected to modification. The prepared nano-magnetic Fe3O4
particles were dispersed in a mixture of solvent 250 mL of abso-
lute ethanol/90 mL of acetonitrile. This mixture was sonicated for
15 min, and then 1.5 mL of NH3·H2O solution (25 wt.%) was
added. After the continuous mechanical stirring for 30 min, 3 mL
of tetrabutyl titanate (TBOT), dissolved in 20 mL of absolute eth-
anol was added drop-wise to the above suspension, under the con-
tinuous mechanical stirring at 30 °C. The reaction mixture was
further mechanically stirred for 1.5 h to obtain Fe3O4@TiO2
core/shell nanoparticles. The obtained product was collected by
magnetic separation and washed, three times with absolute etha-
nol.
The authors gratefully acknowledge Semnan Univer-
sity Research Council for financial support of this work.
REFERENCES
1. Gu, Y. Green Chem. 2012, 14, 2091.
2. Peshkov, V. A.; Pereshivko, O. P.; Van der Eycken, E. V.
Chem. Soc. Rev. 2012, 41, 3790.
3. Seidel, D. Org. Chem. Front. 2014, 1, 426.
4. (a) Shabbir, S.; Lee, Y.; Rhee, H. J. Catal. 2015, 322, 104;
(b) Karimi, B.; Gholinejad, M.; Khorasani, M. H. Chem.
Commun. 2012, 48, 8961; (c) Mirabedini, M.; Motamedi, E.;
Kassaee, M. Z. Chin. Chem. Lett. 2015, 26, 1085; (d) Jiang,
Y.-B.; Zhang, W.-Sh.; Cheng, H.-L.; Liu, Y.-Q.; Yang, R.
Chin. Chem. Lett. 2014, 25, 779; (e) Li, P.; Regati, S.;
Huang, H.-C.; Arman, H. D.; Chen, B.-L.; Zhao, J. C.-G.
Chin. Chem. Lett. 2015, 26, 6.
Preparation of nano-Fe3O4@TiO2/Cu2O core-shell mag-
netic composite: The nano-Fe3O4@TiO2 (0.144 g) was dispersed
in 80 mL of deionized water and then, 5 mL of CuCl2 solution (0.1
mol/L) was added into the aqueous Fe3O4@TiO2 and sonicated
for 15 min. Then, 1.8 mL of (1.0 mol/L) NaOH solution was
added drop wise under ultra sonic radiation. The resulting solu-
tion turned into light blue instantly, indicating the formation of
Cu(OH)2. Eventually, 12 mL of (0.1 mol/L) NH2OH.HCl was im-
mediately injected over 5 sec. into the solution. The solution was
kept in the water bath for 1 h and centrifuged for 3 min. Then the
solution was decanted as much as possible. After the top solution
was decanted, the precipitate was washed with 6 mL of a 1:1 vol-
ume ratio of water and ethanol for three times. The nano-
Fe3O4@TiO2/Cu2O (8:2 molar ratio) was collected as a brown
solid which can be stored in a tight vessel for several months with-
out any changes in colour and activity.
5. Salam, N.; Kundu, S. K.; Mollaa, R. A.; Mondala, P.;
Bhaumik, A.; Manitul Islam, S. RSC Adv. 2014, 4, 47593.
6. Sakaguchi, S.; Mizuta, T.; Ishii, Y. Org. Lett. 2006, 8, 2459.
7. (a) Feng, H.; Ermolat’ev, D. S.; Song, G.; Eycken, Van der E.
V. J. Org. Chem. 2012, 77, 5149; (b) Chen, H. B.; Zhao, Y.;
Liao, Y. RSC Adv. 2015, 5, 37737; (c) Sharma, N.; Sharma,
U. K.; Mishra, N. M.; Van der Eyckena, E. V. Adv. Synth.
Catal. 2014, 356, 1029; (d) Guo, H.; Liu, X.; Xie, Q.; Wang,
L.; Peng, D. L.; Branco, P. S.; Gawande, M. B. RSC Adv.
2013, 3, 19812; (e) Borah, B. J.; Borah, S. J.; Saikia, L.;
Kumar Dutta, D. Catal. Sci. Technol. 2014, 4, 1047.
8. Hosseini-Sarvari, M.; Moeini, F. New J. Chem. 2014, 38,
624.
9. Li, C. J. Acc. Chem. Res. 2010, 43, 581.
10. (a) Stark, W. J.; Stoessel, P. R.; Wohlleben, W.; Hafner, A.
Chem. Soc. Rev. 2015, 44, 5793; (b) Amoozadeh, A.; Kolvari,
E.; Koukabi, N.; Otokesh, S. J. Chin. Chem. Soc. 2015, 62,
501; (c) Amoozadeh, A.; Azhari, S.; Kolvari, E.; Otokesh, S.
J. Chin. Chem. Soc. 2015, 62, 968; (d) Huang, X. X.; Lu, J.
Y.; Lai, H. F.; Wei, L. Q. J. Chin. Chem. Soc. 2015, 62, 52.
11. Fechetea, I.; Wang, Y.; Vedrine, J. C. Catal. Today 2012,
189, 2.
Procedure for synthesis of 1-(1,3-diphenylprop-2-ynyl)
piperidine (5a): Amixture of benzaldehyde (0.106 g, 1.0 mmol),
piperidine (0.093 g, 1.1 mmol), phenylacetylene (0.122, 1.2
mmol) and Fe3O4@TiO2/Cu2O magnetic composite (0.010 g, that
equal to 0.015 mmol Cu2O) were mixed and heated at 100 °C for
55 min under solvent free condition. After completion of the reac-
tion (monitored by TLC), the reaction mixture was cooled to
room temperature and diluted with hot ethanol (10 ml). Then, the
catalyst was separated by an external magnet from the cooled
mixture, washed with acetone, dried in oven and re-used for a
consecutive run under the same reaction conditions. The filtrate
was concentrated and the resulting residue was purified by short
column chromatography on silica gel to afford the desired prod-
uct in excellent yield (95%). The structure of the product was a
defined success to be model of A3 reaction by Mp, IR, 1H NMR
and 13C NMR spectrometer (Table 2, entry 1).
12. Hudson, R.; Feng, Y.; Varma, R. S.; Moores, A. Green Chem.
2014, 16, 4493.
13. (a) Hu, P.; Morabito, J. V.; Tsung, C. K. ACS Catal. 2014, 4,
4409; (b) Mr´owczy´nski, R.; Nanb, A.; Liebscher, J. U. RSC
Adv. 2014, 4, 5927.
14. Wang, X.; Li, Z.; Shi, J.; Yu, Y. Chem. Rev. 2014, 114, 9346.
15. (a) Nemati, F.; Nikkhah, S. H.; Elhampour, A. Chin. Chem.
Lett. 2015, 26, 1397; (b) Nemati, F.; Gharjeh Ghiyaei, A.
Gh.; Notash, B.; Shayegan, M. H.; Amani, V. Tetrahedron
Lett. 2014, 55, 3572; (c) Nemati, F.; Elhampour, A. Sci. Iran.
2012, 19, 1594; (d) Nemati, F.; Elhampour, A. J. Chem. Soc.
2012, 124, 889.
16. Nemati, F.; Heravi, M. M.; Elhampour, A. RSC Adv. 2015, 5,
45775.
6
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© 2016 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
J. Chin. Chem. Soc. 2016, 63, 000-000

JOURNAL OF THE CHINESE
CHEMICAL SOCIETY
A Nano-magnetic Composite for A3 and KA2 Coupling Reaction
17. (a) Nemati, F.; Elhampour, A.; Farrokhi, H.; Bagheri Natanzi,
M. Cat Commun. 2015, 66, 15; (b) Nemati, F.; Heravi, M.
M.; Saeedirad, R. Chin. J. Catal. 2012, 33, 1825; (c) Nemati,
F.; Saeedirad, R. Chin Chem Lett. 2013, 24, 370; (d) Nemati,
F.; Afkham, M. G.; Elhampour, A. Green Chem. Lett. Rev.
2014, 7, 79; (e) Nemati, F.; Sabaqian, S. J. Saudi Chem. Soc.
2014, DOI: 10.1016/j.jscs.2014.04.009. (f) Nemati, F.;
Elhampour, A.; Zulfaghari, S. Phosphorus, Sulfur Silicon
Relat. Elem. 2015, 190, 1692.
Mater. 2011, 21, 792.
20. (a) Mandlimath, T. R.; Sathiyanarayanan, K. I. RSC Adv.
2016, 6, 3117; (b) Kotadia, D. A.; Soni, S. S. Appl. Catal. A
Gen. 2014, 488, 231.
21. Aleem Ali, M. A.; El-Remaily, A.; Hamad, H. A. J. Mol.
Catal. A: Chem. 2015, 404, 148.
22. Cheng, M.; Zhang, Q.; Hu, X. Y.; Li, B. G.; Ji, J. X.; Chan, A.
S. C. Adv. Synth. Catal. 2011, 353, 1274.
23. Kantam, M. L.; Yadav, J.; Laha, S.; Jha, S. Synlett. 2009, 11,
1791.
18. Hu, W.; Liu, B.; Wang, Q.; Liu, Y.; Liu, Y.; Jing, P.; Yu, S.;
Liu, L.; Zhang, J. Chem. Commun. 2013, 49, 7596.
24. Sreedhar, B.; Kumar, A. S.; Reddy, P. S. Tetrahedron Lett.
2010, 51, 1891.
19. Kuo, C. H.; Chu, Y. T.; Song, Y. F.; Huang, M. H. Adv. Funct.
J. Chin. Chem. Soc. 2016, 63, 000-000
© 2016 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.jccs.wiley-vch.de
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