Bis (1(3-trimethoxysilylpropyl)-3-methyl-imidazolium) copper tetrachloride attached to colloidal silica nanoparticles as an efficient catalyst for the preparation of propargylamines

Article abstract of DOI:10.1007/s11164-017-3081-6

Abstract: In this research, we reported the successful preparation of bis (1(3-trimethoxysilylpropyl)-3-methyl-imidazolium) copper tetrachloride tethered to colloidal silica nanoparticles and investigated its catalytic application for one-pot multicompone

Full text of DOI:10.1007/s11164-017-3081-6

Res Chem Intermed
DOI 10.1007/s11164-017-3081-6
Bis (1(3-trimethoxysilylpropyl)-3-methyl-imidazolium)
copper tetrachloride attached to colloidal silica
nanoparticles as an efficient catalyst for the preparation
of propargylamines
1
1
•
Javad Safaei-Ghomi
Hossein Shahbazi-Alavi
•
Seyed Hadi Nazemzadeh
1
Received: 24 March 2017 / Accepted: 12 July 2017
Ó Springer Science+Business Media B.V. 2017
Abstract In this research, we reported the successful preparation of bis (1(3-
trimethoxysilylpropyl)-3-methyl-imidazolium) copper tetrachloride tethered to colloidal
silica nanoparticles and investigated its catalytic application for one-pot multicomponent
preparation of propargylamines under microwave irradiation. Ionic liquid tethered to
colloidal silica nanoparticles have been characterized by H NMR spectroscopy, scanning
electron microscopy, energy dispersive spectroscopy, thermogravimetric analysis, and
dynamic light scattering.
Graphical Abstract
Electronic supplementary material The online version of this article (doi:10.1007/s11164-017-3081-6)
contains supplementary material, which is available to authorized users.
&
Javad Safaei-Ghomi
safaei@kashanu.ac.ir
1
Department of Organic Chemistry, Faculty of Chemistry, University of Kashan,
Kashan, P.O. Box 87317-51167, Islamic Republic of Iran
123

J. Safaei-Ghomi et al.
Keywords Ionic liquid Á Microwave Á Colloidal silica nanoparticles Á
Propargylamines Á Nanocatalyst Á Multi-component reaction
Introduction
Propargylamines exhibit biological activities including anti-Parkinson’s [1, 2],
treatment of Alzheimer’s disease [3, 4], anti-apoptotic [5], and oxidases inhibitors
[
6]. Propargylamines have been used as significant substrates and intermediates for
the synthesis of diverse nitrogen compounds as imidazolidinones [7], oxazolidin-
ones [8], pyrroles [9], pyrrolidines [10], quinolones [11], indolines [12], and
pyridines [13]. Lately, reports have been presented on preparation of chiral allenes
from chiral propargylamines using zinc iodide [14], silver nitrate [15], potassium
gold(III) chloride [16], and zinc bromide [17]. Therefore, the advancement of easy
procedures for the preparation of propargylamines is still favorable and in demand.
The preparation of propargylamines has been achieved using different catalysts such
as CuBr [18], PbS–Au [19], gold(III) salen [20], Cu(OH) –Fe O [21], Zn(OAc)
2-
x
3
4
2
dust [25], copper zeolites [26], NiCl [27], AgY zeolite [28], Cu–MOFs [29], and
H O [22], copper(I) in ionic liquids [23], copper(I)-bisimine complexes [24], zinc
2
2
CuSBA-15 [30]. However, some of the reported methods endure drawbacks
including long reaction times and undesirable reaction conditions. Hence, to avoid
these restrictions, the exploration of an effective, rapidly accessible catalyst with
high catalytic activity for the preparation of propargylamines is still favored.
Recently, preparation and immobilization of ionic liquids (ILs) on nanoparticles
have been widely considered [31–37]. Although ionic liquids encompass some use,
their effective applications have been limited by some problems in their recovery,
which lead to economic and environmental difficulties. These problems can be
dominated by immobilization of ILs onto nanoparticles to obtain heterogeneous
catalysts [38, 39]. Watanabe and co-workers have reported systematic investigations
of colloidal stability, ionic transport, and viscoelastic properties of nanocomposites
based on silica nanoparticles dispersed in ILs [40–43]. The authors exhibited that
the surface chemistry and volume fraction of the particles can be used to control the
stability and flow properties of the nanomaterials. The ionic liquids can be used as
templates to functionalized silica under different conditions [44, 45]. Silica-based
materials, particularly silica nanomaterials, exhibit numerous applications in many
research areas including bionanomaterials, coating materials, and the development
of surface modification of nanocatalysts because of their biocompatibility, chemical
stability, and easy surface modification [46–48]. The structures of 1-ethyl-3-
methylimidazolium (Emim) and 1-butyl-3-methylimidazolium (Bmim) with tran-
2
-
2-
2-
sition metal chloride anions including NiCl4 , CoCl4 , and PdCl4 were studied
49–51]. Herein we reported the preparation of bis (1(3-trimethoxysilylpropyl)-3-
[
methyl-imidazolium) copper tetrachloride tethered to colloidal silica nanoparticles
and investigated its catalytic application for one-pot multicomponent preparation of
propargylamines under microwave irradiation (Scheme 1).
1
23

Bis (1(3-trimethoxysilylpropyl)-3-methyl-imidazolium) copper…
Scheme 1 Preparation of propargylamines using ionic liquid tethered to colloidal silica nanoparticles
Experimental
General
We used the Milestone microwave (Microwave Labstation, MLS GmbH-ATC-FO
300) for synthesis. NMR spectra were recorded on a Bruker 400 MHz spectrometer
with CDCl as solvent and TMS as internal standard. CHN compositions were
3
measured with a Carlo ERBA Model EA 1108 analyzer. DLS was accomplished
with Malvern. In order to study the morphology and particle size of the synthesis
structures MNPs, FE-SEM images and EDS spectra of the products were visualized
by a Sigma ZEISS, Oxford Instruments Field Emission Scanning Electron
Microscope. The temperature-programmed desorption of ammonia (NH -TPD)
3
was obtained using Auto Chem. II 2920 equipment.
Preparation of ionic liquid/nano-colloidal silica
In a typical procedure, 0.098 mL of colloidal silica nanoparticles (LUDOX SM
colloidal silica 30 wt.% suspension in H O) was diluted in 3 mL of deionized water,
2
and 1.8 mmol of 1-(3-trimethoxysilylpropyl)-3-methyl-imidazolium chloride (IL)
was added slowly with continuous stirring during 1 h. Then, 0.15 g of CuCl Á2H O
2
2
was added and refluxed for 24 h. After 24 h, IL functionalized silica nanoparticles
was separated by centrifugation and washed with acetone and methanol for four
2
times, then, IL/Cu /SiO was dried by lyophilization/freeze-drying. The purity of
?
2
2
the resultant IL/Cu /SiO was confirmed using H NMR spectrum. The Cu loading
?
1
2
was measured using XRF to be 4.7 wt.%.
123

J. Safaei-Ghomi et al.
General procedure for the preparation of propargylamines
A mixture of morpholine or piperidine (1.2 mmol), benzaldehydes (1 mmol),
phenylacetylene (1.2 mmol), and 10 mg of bis (1(3-trimethoxysilylpropyl)-3-
methyl imidazolium) copper tetrachloride tethered to silica nanoparticles (nanocat-
alyst) in toluene (15 mL) was irradiated in a microwave oven at 50 °C and 400 W
for the time indicated in Tables 1 and 2. After completion of the reaction (monitored
by TLC), ethyl acetate was added. The catalyst was insoluble in ethyl acetate and it
could, therefore, be recycled by a simple filtration. The crude product obtained was
purified by column chromatography using ethyl acetate-n-hexane to afford the pure
1
13
desired product. The structures of the products were studied using H NMR and
NMR spectra (see supporting information).
C
Table 1 Optimization of reaction conditions using different catalysts under microwave irradiation
300–500 W)
(
b
Entry
Solvent (MWI)
Catalyst
Time (min)
Yield (%)
1
2
3
4
5
6
7
8
9
Toluene (400 W)
No catalyst
45
35
35
35
35
35
30
25
30
30
25
25
25
25
25
7
45
18
33
39
40
60
64
55
68
77
83
86
86
86
H
2
O (500 W)
CuCl
Fe
ZrOCl
ZnO (4 mol%)
Ni(OAC) (2 mol%)
IL/silica (200–600 mesh) (15 mg)
IL/nano-Fe (12 mg)
2
(5 mol%)
Toluene (400 W)
Toluene (400 W)
Toluene (400 W)
Toluene (400 W)
Toluene (400 W)
Toluene (400 W)
O (4 mol%)
3 4
2
(3 mol%)
2
3 4
O
a
CH
2
Cl
2
(400 W)
IL /nano-colloidal silica (10 mg)
IL/nano-colloidal silica (10 mg)
IL/nano-colloidal silica (10 mg)
IL/nano-colloidal silica (8 mg)
IL/nano-colloidal silica (10 mg)
IL/nano-colloidal silica (12 mg)
IL/nano-colloidal silica (10 mg)
1
1
1
1
1
1
0
1
2
3
4
5
THF (400 W)
Toluene (300 W)
Toluene (400 W)
toluene (400 W)
Toluene (400 W)
Toluene (500 W)
Phenylacetylene (1.2 mmol), morpholine (1.2 mmol), and benzaldehyde (1 mmol)
a
Bis (1(3-trimethoxysilylpropyl)-3-methyl-imidazolium) copper tetrachloride = ionic liquid = IL
b
Isolated yield
1
23

Bis (1(3-trimethoxysilylpropyl)-3-methyl-imidazolium) copper…
Table 2 Synthesis of propargylamines using ionic liquid/nano-colloidal silica (nanocatalyst)
a
Entry
Amine
R
Product
Time (min)
Yield (%)
1
2
3
4
5
6
7
8
9
Morpholine
Morpholine
Morpholine
Morpholine
Morpholine
Piperidine
Piperidine
Piperidine
Piperidine
Piperidine
Piperidine
Piperidine
H
4a
4b
4c
4d
4e
4f
25
25
30
30
25
25
30
25
30
25
25
25
86
90
82
84
88
94
82
90
85
93
88
92
4-Cl
2-Me
4-Me
2-Cl
4-NO
2
4-OMe
2-Cl
3-Me
4-Br
H
4g
4h
4i
1
1
1
0
1
2
4j
4k
4l
4-Cl
Phenylacetylene (1.2 mmol), morpholine or piperidine (1.2 mmol) arylaldehydes (1 mmol), and
nanocatalyst (10 mg) in toluene under microwave irradiation (400 W)
a
Isolated yield
Results and discussion
Characterization of the nanocatalyst
1
Figure 1a and b exhibit the H NMR spectra for the 1(3-trimethoxysilylpropyl)-3-
methyl-imidazolium chloride and bis (1(3-trimethoxysilylpropyl)-3-methyl-imida-
zolium) copper tetrachloride tethered to colloidal silica nanoparticles in dimethyl
sulfoxide (DMSO), respectively. The H NMR spectra of both materials are
consistent with expected results for untethered and silica-tethered ionic liquids.
1
3
Meanwhile, the C NMR spectrum for the bis (1(3-trimethoxysilylpropyl)-3-
methyl-imidazolium) copper tetrachloride tethered to colloidal silica nanoparticles
in DMSO is shown in Figure S1 (see supplementary information).
Figure 2 shows FE-SEM image of bis (1(3-trimethoxysilylpropyl)-3-methyl-
imidazolium) copper tetrachloride tethered to silica nanoparticles (nanocatalyst).
The SEM image displays particles with diameters in the nanometer range. Figure 3
represents the TEM (Transmission electron microscope) image of nanocatalyst.
These nanoparticles with a diameter of 25–35 nm exhibit a uniform spherical shape.
123

J. Safaei-Ghomi et al.
1
23

Bis (1(3-trimethoxysilylpropyl)-3-methyl-imidazolium) copper…
1
bFig. 1 a H NMR spectrum of 1(3-trimethoxysilylpropyl)-3-methyl-imidazolium chloride and b bis
(1(3-trimethoxysilylpropyl)-3-methyl-imidazolium) copper tetrachloride tethered to colloidal silica
nanoparticles (nanocatalyst) in dimethyl sulfoxide (DMSO)
Fig. 2 FE-SEM image of
nanocatalyst
Fig. 3 TEM image of nanocatalyst
In order to investigate the size distribution of nanocatalysts, DLS (dynamic light
scattering) measurements of the nanoparticles were showed in Fig. 4.
The elemental compositions of the nanocatalyst were studied by energy
dispersive spectroscopy (EDS). EDS confirmed the attendance of Si, O, N, C, Cl,
and Cu in the compound (Fig. 5).
123

J. Safaei-Ghomi et al.
Fig. 4 DLS of nanocatalyst
3
3
2
2
1
1
500
000
500
000
500
000
SiK
EDS
O K
N K
CuL
ClK
ClK
5
00
CuK
CuK
keV
15
0
0
5
10
Fig. 5 EDS of nanocatalyst
Thermogravimetric analysis (TGA) considers the thermal stability of the ionic
liquid of untethered to SiO (pure ionic liquid) and silica-tethered ionic liquids
2
(
Fig. 6). The curve displays a weight loss about 36.8% for ionic liquid/nano-
colloidal silica from 240 to 550 °C, resulting from the destruction of organic spacer
attaching to the nanoparticles. Hence, the nanocatalyst was stable up to 240 °C,
confirming that it could be stably used in organic reactions at temperatures in the
range of 80–160 °C.
1
23

Bis (1(3-trimethoxysilylpropyl)-3-methyl-imidazolium) copper…
Fig. 6 TGA of IL and nanocatalyst
The amount of acid sites can be calculated by NH -TPD. The total acidity (mmol
3
-
1
NH g ) of catalyst was 0.32. Lewis acidic ionic liquids with anions based on
3 cat
CuCl are mainly responsible for acidity activity.
2
Investigation of catalytic activity for synthesis of propargylamines
After characterizing the nanocatalysts, we evaluated and optimized diverse reaction
parameters for the preparation of propargylamines by the reaction of pheny-
lacetylene, morpholine, and benzaldehyde as a model reaction. To obtain the desire
reaction conditions for the synthesis of compound 4a, we investigated some
catalysts and solvents under microwave irradiation (Table 1). Screening of different
catalysts such as CuCl , Fe O , ZrOCl , ZnO, Ni(OAC) , and nanocatalyst (ionic
2
3
4
2
2
liquid/nano-colloidal silica) revealed ionic liquid/nano-colloidal silica as the most
effective catalyst to perform this reaction under microwave irradiation. In further
studies on the catalyst loading, we realized that yield of compound 4a remained
almost the same when 12 mg of liquid/nano-colloidal silica was used (Table 1). Use
of lower catalyst loading (8 mg) afforded 4a in 83% yield. In this study, microwave
irradiation is used as a green and beneficial method for preparation of propargy-
lamines. In order to investigate the effect of intensity of microwave power on
reaction, the reaction was also performed at different powers of the microwave
irradiation (Table 1). The best results were obtained under microwave irradiation
(
(
400 W) in toluene and the reaction gave satisfying results in the presence of bis
1(3-trimethoxysilylpropyl)-3-methyl-imidazolium) copper tetrachloride (ionic liq-
uid) tethered to colloidal silica nanoparticles as catalyst.
With these acceptable results in hand (Table 1, entry 13), we then investigated
the feasibility of the reaction using diverse aromatic aldehydes as substrates. The
123

J. Safaei-Ghomi et al.
Scheme 2 Mechanism for the synthesis of propargylamines using ionic liquid-tethered to colloidal silica
nanoparticles
results show the present catalytic method is extensible to a wide diversity of
substrates to create a variety-oriented library of propargylamines.
A proposed mechanism for the synthesis of propargylamines using nanocatalyst
is shown in Scheme 2. At the start, the activated aldehyde by nanocatalyst is
condensed with the secondary amine to give an iminium ion in situ, meanwhile, the
nanocatalyst activates the C–H bond of the terminal alkyne to generate a copper-
acetylide intermediate. The copper-acetylide intermediate then undergoes nucle-
ophilic attack onto the iminium ion to give propargylamines [52–55]. In the present
II
study Cu -IL/SiO itself acts as the active catalyst generating an initial copper(II)
2
II
acetylide intermediate by the reaction between a Cu species in IL/SiO with a
2
terminal alkyne. This copper acetylide intermediate reacts with the iminium ion
generated in situ from activated aldehyde and amine to give the corresponding
II
propargylamine. The Cu -IL/SiO catalyst is regenerated for subsequent reactions.
2
II
Cu specie in ionic liquid is more accessible to organic substrates than other
II
catalysts containing of Cu species.
We also considered reusability of the bis (1(3-trimethoxysilylpropyl)-3-methyl-
imidazolium) copper tetrachloride tethered to colloidal silica nanoparticles (IL/
2
Cu SiO ) as a catalyst under microwave irradiation for the synthesis of product
?/
2
4
a, and it was found that product yields decreased to a small extent on each reuse
1
23

Bis (1(3-trimethoxysilylpropyl)-3-methyl-imidazolium) copper…
(
run 1, 86%; run 2, 86%; run 3, 85%; run 4, 85%; run 5, 84%). (Fig S2; see
supplementary information). After completion of the reaction, ethyl acetate was
added. The catalyst was insoluble in ethyl acetate and it could, therefore, be
recycled by centrifuging. The nanoparticles were then washed three to four times
with dichloromethane. The recycling ability of the catalyst was tested for five runs,
providing almost similar yields of the desired product. The extreme stability of the
nanocatalyst is mainspring of the continuous and high catalytic activity. The
morphology of nanoparticles was investigated by scanning electron microscopy
(
SEM) before use and after reusing five times, as shown in Fig S3 (see
supplementary information). Interestingly, the shape and size of the nanoparticles
remained unchanged before and after reaction. We suppose that, this is also the
possible reason for the extreme stability of the nanoparticles presented herein.
Conclusion
In conclusion, we demonstrated an efficient method for the preparation of
propargylamines using ionic liquid tethered to colloidal silica nanoparticles under
microwave irradiation. The present catalyst provides active sites for the synthesis of
propargylamines. The advantages of this method are the use of an efficient catalyst,
little catalyst loading, short reaction times, use of microwaves as clean method, and
excellent yields.
Acknowledgements The authors are grateful to the University of Kashan for supporting this work by
Grant NO: 463562/VI.
References
1
2
3
4
. M. Yogev-Falach, T. Amit, O. Bar-Am, M.B.H. Youdim, FASEB J. 17, 2325 (2003)
. J.J. Chen, D.M. Swope, J. Clin. Pharmacol. 45, 878 (2005)
. I. Bolea, A. Gella, M. Unzeta, J. Neural. Transm. 120, 893 (2013)
. A. Samadi, C. De Los R ´ı os, I. Bolea, M. Chioua, I. Iriepa, I. Moraleda, M. Bartolini, V. Andrisano, E.
G a´ lvez, C. Valderas, M. Unzeta, J. Marco-Contelles, Eur. J. Med. Chem. 52, 251 (2012)
. W. Maruyama, T. Yamamoto, K. Kitani, M.C. Carrillo, M. Youdim, M. Naoi, Mech. Ageing Dev.
5
116, 181 (2000)
6
7
8
9
. H.B. Jeon, L.M. Sayre, Biochem. Biophys. Res. Commun. 304, 788 (2003)
. M. Shi, Y.M. Shen, J. Org. Chem. 67, 16 (2002)
. E.S. Lee, H.S. Yeom, J.H. Hwang, S. Shin, Eur. J. Org. Chem. 2007, 3503 (2007)
. J. Weng, Y. Chen, B. Yue, M. Xu, H. Jin, Eur. J. Org. Chem. 2015, 3164 (2015)
10. S. Morikawa, S. Yamazaki, Y. Furusaki, N. Amano, K. Zenke, K. Kakiuchi, J. Org. Chem. 71, 3540
(2006)
1
1
1
1
1
1
1
1. Y. Luo, Z. Li, C.J. Li, Org. Lett. 7, 2675 (2005)
2. D. Chernyak, N. Chernyak, V. Gevorgyan, Adv. Synth. Catal. 352, 961 (2010)
3. D.N. Penk, N.A. Robinson, H.M. Hill, M. Turlington, Tetrahedron Lett. 58, 470 (2017)
4. M. Periasamy, P.O. Reddy, N. Sanjeevakumar, Eur. J. Org. Chem. 2013, 3866 (2013)
5. V.K.Y. Lo, C.Y. Zhou, M.K. Wong, C.M. Che, Chem. Commun. 46, 213 (2010)
6. V.K.Y. Lo, M.K. Wong, C.M. Che, Org. Lett. 10, 517 (2008)
7. M. Periasamy, N. Sanjeevakumar, M. Dalai, R. Gurubrahamam, P.O. Reddy, Org. Lett. 14, 2932
(2012)
123

J. Safaei-Ghomi et al.
1
1
2
2
2
2
2
2
8. N. Gommermann, C. Koradin, K. Polborn, P. Knochel, Angew. Chem. Int. Ed. 42, 5763 (2003)
9. L.L. Chng, J. Yang, Y. Wei, J.Y. Ying, Adv. Synth. Catal. 351, 2887 (2009)
0. V.K.Y. Lo, Y. Liu, M.K. Wong, C.M. Che, Org. Lett. 8, 1529 (2006)
1. M.J. Aliaga, D.J. Ram o´ n, M. Yus, Org. Biomol. Chem. 8, 43 (2010)
2. E. Ramu, R. Varala, N. Sreelatha, S.R. Adapa, Tetrahedron Lett. 48, 7184 (2007)
3. S.B. Park, H. Alper, Chem. Commun. 2005, 1315 (2005)
4. F. Colombo, M. Benaglia, S. Orlandi, F. Usuelli, G. Celentano, J. Org. Chem. 71, 2064 (2006)
5. M.L. Kantam, V. Balasubrahmanyam, K.B.S. Kumar, G.T. Venkanna, Tetrahedron Lett. 48, 7332
(2007)
2
2
2
2
3
3
6. M.K. Patil, M. Keller, B.M. Reddy, P. Pale, J. Sommer, Eur. J. Org. Chem. 2008, 4440 (2008)
7. S. Samai, G.C. Nandi, M.S. Singh, Tetrahedron Lett. 51, 5555 (2010)
8. R. Maggi, A. Bello, C. Oro, G. Sartori, L. Soldi, Tetrahedron 64, 1435 (2008)
9. I. Luz, F.X.L. Xamena, A. Corma, J. Catal. 285, 285 (2012)
0. M. Srinivas, P. Srinivasu, S.K. Bhargava, M.L. Kantam, Catal. Today 208, 66 (2013)
1. J. Huang, T. Jiang, H. Gao, B. Han, Z. Liu, W. Wu, Y. Chang, G. Zhao, Angew. Chem. Int. Ed. 43,
1397 (2004)
3
3
3
3
3
3
3
2. R. Sandaroos, S. Damavandi, H.R. Molaei, Res. Chem. Intermed. 41, 1517 (2015)
3. D. Habibi, A. Shamsian, Res. Chem. Intermed. 41, 6245 (2015)
4. J. Safaei-Ghomi, R. Sadeghzadeh, H. Shahbazi-Alavi, RSC. Adv. 6, 33676 (2016)
5. H. Valizadeh, M. Amiri, A. Shomali, F. Hosseinzadeh, J. Iran. Chem. Soc. 8, 495 (2011)
6. M.V. Khedkar, T. Sasaki, B.M. Bhanage, ACS Catal. 3, 287 (2013)
7. J.Y. Jung, J.B. Kim, A. Taher, M.J. Jin, Bull. Korean Chem. Soc. 30, 3082 (2009)
8. S.S. Moganty, S. Srivastava, Y. Lu, J.L. Schaefer, S.A. Rizvi, L.A. Archer, Chem. Mater. 24, 1386
(2012)
39. O.P. Khatri, K. Adachi, K. Murase, K.I. Okazaki, T. Torimoto, N. Tanaka, S. Kuwabata, H. Sugi-
mura, Langmuir 24, 7785 (2008)
4
4
4
4
4
4
4
4
0. K. Ueno, A. Inaba, M. Kondoh, M. Watanabe, Langmuir 24, 5253 (2008)
1. K. Ueno, A. Inaba, Y. Sano, M. Kondoh, M. Watanabe, Chem. Commun. 24, 3603 (2009)
2. K. Ueno, S. Imaizumi, K. Hata, M. Watanabe, Langmuir 25, 825 (2009)
3. K. Ueno, Y. Sano, A. Inaba, M. Kondoh, M. Watanabe, J. Phys. Chem. B 114, 13095 (2010)
4. T. Wang, H. Kaper, M. Antonietti, B. Smarsly, Langmuir 23, 1489 (2007)
5. Y. Zhou, J.H. Schattka, M. Antonietti, Nano Lett. 4, 477 (2004)
6. H. Wei, L. Zhou, J. Li, J. Liu, E. Wang, J. Colloid Interface Sci. 321, 310 (2008)
7. M. Cho, W.S. Cho, M. Choi, S.J. Kim, B.S. Han, S.H. Kim, H.O. Kim, Y.Y. Sheen, J. Jeong, Toxicol.
Lett. 189, 177 (2009)
4
4
5
5
5
5
5
8. J. Safaei-Ghomi, H. Shahbazi-Alavi, P. Babaei, Z. Naturforsch. 71, 849 (2016)
9. P.B. Hitchcock, K.R. Seddon, T. Welton, J. Chem. Soc., Dalton Trans. 17, 2639 (1993)
0. J.E.L. Dullius, P.A.Z. Suarez, S. Einloft, R.F. de Souza, J. Dupont, Organometallics 17, 815 (1998)
1. C. Zhong, T. Sasaki, M. Tada, Y. Iwasawa, J. Catal. 242, 357 (2006)
2. B. Karimi, M. Gholinejad, M. Khorasani, Chem. Commun. 48, 8961 (2012)
3. Z. Zarei, B. Akhlaghinia, RSC Adv. 6, 106473 (2016)
4. J.V. Madhav, B.S. Kuarm, P. Someshwar, B. Rajitha, Y.T. Reddy, P.A. Crooks, Synth. Commun. 38,
3215 (2008)
55. S. Kaur, M. Kumar, V. Bhalla, Chem. Commun. 51, 16327 (2015)
1
23