Silica sulfuric acid-coated Fe3O4 nanoparticles as a highly efficient and reusable solid acid catalyst for the green synthesis of 2, 3-dihydroquinazolin-4(1H)-ones under solvent-free conditions

Article abstract of DOI:10.2174/1570178614666170711144740

An efficient and eco-friendly procedure for the synthesis of 2, 3-dihydroquinazolin-4(1H)- ones and spiroquinazolinones in the presence of sulfuric acid functionalized silica-coated magnetite nanoparticles under solvent-free conditions has been described. The reactions are completed in short times, and the products are obtained in high isolated yields without any undesirable side reaction. This method has several advantages, including short reaction time, facile operation, easy work-up, ecofriendly reaction conditions, high isolated yields, and reusability of the catalyst. The catalyst could be easily separated and recovered from the reaction mixture by an external magnet and reused in subsequent reactions with no considerable loss in activity.

Full text of DOI:10.2174/1570178614666170711144740

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39
Letters in Organic Chemistry, 2018, 15, 39-44
RESEARCH ARTICLE
ISSN: 1570-1786
eISSN: 1875-6255
Silica Sulfuric Acid-coated Fe3O4 Nanoparticles as a Highly Efficient and
Reusable Solid Acid Catalyst for the Green Synthesis of 2,3-
Dihydroquinazolin-4(1H)-ones under Solvent-free Conditions
Impact
Factor:
0.73
BENTHAM
S
CIENCE
Monire Beyki1 and Mehdi Fallah-Mehrjardi1,2,*
2
1Department of Chemistry, Payame Noor University (PNU), Tehran, 19395-3697, Iran; Research Center of Environ-
mental Chemistry, Payame Noor University, Ardakan, Yazd, Iran
Abstract: An efficient and eco-friendly procedure for the synthesis of 2,3-dihydroquinazolin-4(1H)-
ones and spiroquinazolinones in the presence of sulfuric acid functionalized silica-coated magnetite
A R T I C L E H I S T O R Y
nanoparticles under solvent-free conditions has been described. The reactions are completed in short
times, and the products are obtained in high isolated yields without any undesirable side reaction. This
Received: February 04, 2017
method has several advantages, including short reaction time, facile operation, easy work-up, eco-
Revised: June 09, 2017
Accepted: June 11, 2017
friendly reaction conditions, high isolated yields, and reusability of the catalyst. The catalyst could be
DOI:
easily separated and recovered from the reaction mixture by an external magnet and reused in subse-
10.2174/1570178614666170711144740
quent reactions with no considerable loss in activity.
Keywords: 2,3-Dihydroquinazolin-4(1H)-ones, Fe3O4@SiO2-SO3H, nanomagnetic solid acid catalyst, cyclocondensation, sol-
vent-free, green synthesis.
1. INTRODUCTION
Several methods for the synthesis of 2,3-dihydroquinazolin-
4(1H)-ones have been reported [15-20]. The cyclocondensa-
tion of aldehydes and ketones with anthranilamide (2-
aminobenzamide), and three component reaction of isatoic
anhydride and an aromatic aldehyde with ammonium acetate
or primary amines are the general methods for the synthesis
of 2,3-dihydroquinazolin-4(1H)-ones. In the recent decade,
various catalysts have been used to catalyze these reactions
such as Sc(OTf)3 [21], NH4Cl [22], H3PW12O40 [23], mag-
netic Fe3O4 nanoparticles [24], SrCl2.6H2O [25], ZrCl4 [26],
Amberlyst-15 [27, 28], 2-(N-morpholino) ethanesulfonic
acid (MES) [29], bis(glycerol)boric acid (H[Gly2B]) [30], p-
TsOH [31, 32], Poly(VPyPS)-PW [33], metal-CNTs [34],
nanocrystalline sulfated zirconia [35], Y(OTf)3 [36], and
titanium silicon oxide nanopowder [37]. These catalysts are
useful to facilitate the synthesis of desired products, how-
ever, most of the reported procedures suffer from some limi-
tations such as long reaction time, low product yields, the
use of hazardous solvents, difficulty in work-up and lack of
reusability of the catalyst. Therefore, mild, simple and effec-
tive processes for the synthesis of 2,3-dihydroquinazolin-
4(1H)-ones are still in demand.
Optimal use of material and energy, and an efficient
waste management can be recognized as important factors
for environmental protection. To realize this target, in recent
decades, remarkable papers have appeared efficient solvent-
free reactions [1-4]. This method has many advantages such
as reduced pollution, eco-friendly reaction conditions, low
cost, simplicity in operation, short reaction time, easier
work-up, and green aspects by avoiding hazardous organic
solvents. In addition, from the green and environmental ac-
ceptability, recently more attention has been paid to the ap-
plication of nanomagnetic solid acid catalysts in organic
transformations [5-7]. The main advantages of these cata-
lysts are simple separation of the catalyst from the reaction
mixture, and high efficiency, recyclability and reusability of
the catalyst.
2,3-Dihydroquinazolin-4(1H)-ones are an important class
of nitrogen-containing heterocyclic compounds have been
reported a wide range of biological and pharmaceutical ac-
tivities [8, 9]. 2,3-Dihydroquinazolinone derivatives can be
easily oxidized to quinazolin-4(3H)-ones [10, 11], which also
have biological activities and exist in a variety of natural prod-
ucts, pharmaceutical candidates and agrochemicals [12-14].
In recent years, sulfuric acid functionalized silica-coated
magnetite nanoparticles (Fe3O4@SiO2-SO3H) as recyclable
strong solid acid catalyst opens up a new path to present an
efficient system for facilitating catalyst recovery in different
organic reactions [38-41]. Because of the importance of 2,3-
dihydroquinazolin-4(1H)-ones and the catalytic strength of
*Address correspondence to this author at the Department of Chemistry,
Payame Noor University, Tehran, 19395-3697, Iran; Tel/Fax: +98
3532220011; E-mail: fallah.mehrjerdi@pnu.ac.ir
1875-6255/18 $58.00+.00
© 2018 Bentham Science Publishers

40 Letters in Organic Chemistry, 2018, Vol. 15, No. 1
Beyki and Fallah-Mehrjardi
O
O
Fe3O4@SiO2-SO3H in organic reactions, we wish to report a
new method for the synthesis of 2,3-dihydroquinazolin-
4(1H)-ones through the cyclocondesation of aldehydes and
ketones with anthranilamide in the presence of catalytic
amounts of Fe3O4@SiO2-SO3H under solvent-free condi-
tions.
O
NH2
NH
Fe3O4@SiO2-SO3H
Solvent-free, r.t.
R1
+
R1
R2
NH2
N
H
R2
2-15 min.
82-96%
Scheme (1). Fe3O4@SiO2-SO3H catalyzed synthesis of 2,3-
dihydroquinazolin-4(1H)-ones.
2. RESULTS AND DISCUSSION
Fe3O4@silica sulfuric acid core-shell nanocomposite
(Fe3O4@SiO2-SO3H) has received remarkable attention as an
inexpensive, readily available, non-toxic and reusable cata-
lyst for various organic transformations, affording the corre-
sponding products in high yields [38-41]. However, to the
best of our knowledge there has been no report on the use of
this solid acid catalyst for the synthesis of quinazolinones and
their derivatives. We observed that Fe3O4@SiO2-SO3H is an
efficient catalyst for the synthesis of 2,3-dihydroquinazolin-
4(1H)-ones through the cyclocondesation of aldehydes and
ketones with anthranilamide under solvent-free conditions
(Scheme 1).
The Fe3O4@SiO2-SO3H catalyst was prepared following
the reported procedure [39]. Fe3O4 nanoparticles were syn-
thesized by the co-precipitation of FeCl2 and FeCl3 in am-
monia solution. To improve the chemical stability of magnet-
ite nanoparticles, their surface engineering was successfully
performed by the suitable deposition of silica onto nanopar-
ticles surface by the ammonia-catalyzed hydrolysis of tetra-
ethylorthosilicate (TEOS). Next, The SiO2 spheres served as
support for the immobilization of SO3H groups by simple
mixing of core-shell composite and chlorosulfonic acid in
CH2Cl2 (Scheme 2). The structure of the catalyst confirmed
OH
OH
OH
OH
FeCl3.6H2O
SiO2
TEOS, EtOH/H2O, N2
NH4OH, r.t., 12 h
NH4OH, N2
80 oC, 30 min
Fe3O4
MNP
Fe3O4
MNP
+
OH
OH
FeCl2.4H2O
ClSO3H, dry CH2Cl2
r.t., 30 min
OSO3H
SiO2
Fe3O4
MNP
OSO3H
OSO3H
Scheme (2). Schematic diagram for the synthesis of Fe3O4@SiO2-SO3H.
Fig. (1). FT-IR spectra of the bare Fe3O4 (a), Fe3O4@SiO2 (b) and Fe3O4@SiO2-SO3H (c) nanoparticles.

Silica Sulfuric Acid-coated Fe3O4 Nanoparticles as a Highly Efficient
Letters in Organic Chemistry, 2018, Vol. 15, No. 1 41
After preparation and characterization of the catalyst,
initially, the reaction condition was optimized in the reaction
of anthranilamide and benzaldehyde as model reaction. The
results of optimization experiments were summarized in
Table 1. The results clearly show that although this reaction
proceeded in ethanol at room temperature and under reflux
conditions, the best result was obtained under solvent-free
conditions at room temperature. The reaction in the absence
of catalyst did not complete after 2h in refluxing EtOH. The
model reaction was performed in the presence of various
amounts of Fe3O4@SO3H and Fe3O4@SiO2-SO3H as cata-
lyst. In the terms of reaction time and the yield of the prod-
uct, 0.025 g Fe3O4@SiO2-SO3H was selected as the best
amount of the catalyst.
by FT-IR spectra (Fig. 1), SEM image (Fig. 2), EDS (Fig. 3)
and XRD pattern (Fig. 4).
Following the obtained results, the reaction of anthra-
nilamide and benzaldehyde was carried out in the presence
of 0.025 g Fe3O4@SiO2-SO3H under solvent-free conditions
at room temperature and the corresponding 2,3-
dihydroquinazolin-4(1H)-one was obtained in 93% yield
(Table 2, entry 1).
Fig. (2). SEM image of Fe3O4@SiO2-SO3H nanoparticles.
Fig. (3). EDS spectra of Fe3O4@SiO2-SO3H nanoparticles.
Fig. (4). XRD pattern of Fe3O4@SiO2-SO3H nanoparticles.

42 Letters in Organic Chemistry, 2018, Vol. 15, No. 1
Beyki and Fallah-Mehrjardi
Table 1. The optimization of the cyclocondensation reaction of anthranilamide with benzaldehyde.
Entry
Catalyst (g)
Solvent
Temp. (°C)
Time (min)
Yield (%)
1
2
No catalyst
EtOH
EtOH
EtOH
EtOH
H2O
reflux
r.t.
120
20
trace
92
Fe3O4@SiO2-SO3H (0.05 g)
Fe3O4@SiO2-SO3H (0.05 g)
Fe3O4@SiO2-SO3H (0.025 g)
Fe3O4@SiO2-SO3H (0.05 g)
Fe3O4@SiO2-SO3H (0.05 g)
Fe3O4@SiO2-SO3H (0.05 g)
Fe3O4@SiO2-SO3H (0.05 g)
Fe3O4@SiO2-SO3H (0.05 g)
Fe3O4@SO3H (0.05 g)
3
reflux
r.t.
10
90
4
60
89
5
r.t.
90
87
6
MeCN
CH2Cl2
PhMe
Et2O
r.t.
120
120
120
120
60
trace
trace
trace
trace
87
7
r.t.
8
r.t.
9
r.t.
10
11
12
EtOH
Neat
r.t.
Fe3O4@SiO2-SO3H (0.05 g)
Fe3O4@SiO2-SO3H (0.025 g)
r.t.
1.5
2
90
Neat
r.t.
93
Table 2. Synthesis of 2,3-dihydroquinazolin-4(1H)-ones catalyzed by Fe3O4@SiO2–SO3H under solvent-free conditions.
m.p. (°C)
Entry
Aldehyde/Ketone
Producta
Time (min)
Yield (%)b
Found
Reported
1
2
Benzaldehyde
4-Methylbenzaldehyde
4-Methoxybenzaldehyde
2-Hydroxybenzaldehyde
2-Chlorobenzaldehyde
3-Chlorobenzaldehyde
4-Chlorobenzaldehyde
3-Nitrobenzaldehyde
2,5-Dimethoxybenzaldehyde
3,4-Dihydroxybenzaldehyde
4-Dimethylaminobenzaldehyde
Cinnamaldehyde
3a
3b
3c
3d
3e
3f
2
3
2
2
7
6
7
5
8
6
7
8
6
9
2
15
5
4
2
93
90
94
96
96
85
83
92
88
89
84
87
95
90
93
95
85
82
84
220-222
231-233
187-189
223-226
207-209
185-187
205-207
183-184
167-169
187-190
209-210
240-243
166-168
260-262
217-219
197-200
214-215
>300
219-220 [33]
230-232 [33]
185-187 [33]
220-221 [29]
207-209 [30]
185-186 [42]
205-207 [30]
182-184 [30]
164-165 [42]
-
3
4
5
6
7
8c
9d
3g
3h
3i
10d
11d
12
13
14c
15c
16c
17c
18d
19d,e
3j
3k
3l
208-210 [29]
224-226 [43]
165-167 [33]
264-266 [32]
220-222 [32]
-
2-Furaldehyde
3m
3n
3o
3p
3q
3r
Cyclopentanone
Cyclohexanone
Cycloheptanone
Isatin
214-216 [22]
>300 [32]
1,4-Cyclohexanedione
1,4-Cyclohexanedione
3s
>300
>300 [32]
a) All of the products were characterized by IR, and 1H and 13C NMR, and their spectra were compared with those of the authentic samples.
b) Isolated yields.
c) Reaction was carried out at 70°C in an oil bath.
d) Reaction was carried out at 90°C in an oil bath.
e) Anthranilamide: ketone in a 2:1 ratio.
The scope and generality of this procedure was investi-
gated in the reaction of various types of aldehydes and ke-
tones with anthranilamide (Table 2). Aldehydes with both
electron-donating and electron-withdrawing substituents
were reacted with anthranilamide at the same reaction condi-
tions and the corresponding products were obtained in excel-

Silica Sulfuric Acid-coated Fe3O4 Nanoparticles as a Highly Efficient
Letters in Organic Chemistry, 2018, Vol. 15, No. 1 43
lent yields (Table 2, entries 2-11). Cinnamaldehyde and 2-
furylaldehyde as starting materials were also reacted under
optimized reaction conditions and the corresponding 2,3-
dihydroquinazolin-4(1H)-ones were produced in high yields
(Table 2, entries 12 and 13). Cyclic ketones and diketones
were also condensed with anthranilamide successfully and
the corresponding spiroquinazolinones were obtained in
good to excellent yields (Table 2, entries 14-18). When
the reaction was carried out with anthranilamide: 1,4-
cyclohexanedione in 2:1 ratio, we found that the dispiro
compound formed (Table 2, entry 19) was evidenced from
the 1H, 13C NMR spectra.
3. EXPERIMENTAL
3.1. General Procedures
All of the commercially available chemicals were pur-
chased from Fluka, Aldrich and Merck and used without
further purification. Fe3O4, Fe3O4@SiO2 and Fe3O4@SiO2-
SO3H were prepared according to the reported method [39].
All of the products were characterized for their physical
properties and by comparison with authentic samples. Prod-
ucts were characterized by comparison of their physical data,
IR, 1H-NMR and 13C-NMR spectra with known samples.
NMR spectra were recorded in CDCl3 on a Bruker Advance
DPX 400 MHz instrument spectrometer using TMS as inter-
nal standard. IR spectra were recorded on a BOMEM MB-
Series 1998 FT-IR spectrometer. The purity determination of
the products and reaction monitoring were accomplished by
TLC on silica gel PolyGram SILG/UV 254 plates. X-ray
diffraction (XRD) patterns of samples were taken on a Phil-
ips X-ray diffractometer Model PW 1840. The particle mor-
phology was examined by SEM (Philips XL30 scanning
electron microscope).
It is worthy to note that the catalyst can be reused several
times with no appreciable loss in its activity. The catalyst
was separated and recovered by an external magnet, and then
it was reused at least four times for facile condensation of
benzaldehyde and anthranilamide, and produced desired
product in 93%, 91%, 88% and 85% yield, respectively (Ta-
ble 3).
Table 3. Reusability of the catalyst in the reaction of anthra-
nilamide with benzaldehyde.
3.2. Preparation of the Catalyst
The nano Fe3O4@SiO2-SO3H was prepared according to
the reported method [39].
Run
Time (min)
Yield (%)
1
2
3
4
2
2
2
2
93
91
88
85
3.3. General Procedure for the Synthesis of 2,3-
dihydroquinazolin-4(1H)-ones
Fe3O4@SiO2-SO3H (0.05 g) was added to the 1:1 mixture
of anthranilamide (1 mmol) and aldehydes or ketones
(1 mmol). The mixture was stirred at room temperature (or in
an oil bath at 70-100°C) for the appropriate time as shown in
Table 2. After completion of the reaction, as indicated by
TLC (ethyl acetate:n-hexane 1:1), and cooling, hot ethanol
(5 mL) was added to the mixture and stirred for 10 min. In
the presence of an external magnet, the nanocatalyst was
removed and then extracted solution was cooled to room
temperature to recrystallize to afford the corresponding
By comparison, the obtained results for the synthesis of
2,3-dihydroquinazolin-4(1H)-one from benzaldehyde in the
presence of various catalysts are given in Table 4. As shown
in Table 4, Fe3O4@SiO2-SO3H has greater efficiency and
shorter reaction time than other catalysts.
Table 4. Comparison of various catalysts for the synthesis of 2,3-dihydroquinazolin-4(1H)-one from benzaldehyde.
Entry
Catalyst
Conditions
Time (min)
Yield (%)
Ref.
1
2
Ga(OTf)3
Sc(OTf)3
EtOH, 70°C
EtOH, 70°C
EtOH, r.t.
55
25
15
8
83
92
92
94
93
95
93
95
90
95
93
93
[19]
[21]
3
NH4Cl
[22]
4
H3PW12O40
SrCl2.6H2O
ZrCl4
H2O, r.t.
[23]
5
EtOH/H2O, reflux
EtOH, r.t.
42
25
150
10
10
6
[24]
6
[25]
7
MES
EtOH/H2O, 60°C
EtOH/H2O, MW
60°C
[26]
8
MES
[26]
9
H[Gly2B]
Poly(VPyPS)-PW
Y(OTf)3
[27]
10
11
12
EtOH, Ul.
[30]
EtOH, r.t.
90
2
[33]
Fe3O4@SiO2-SO3H
r.t.
This work

44 Letters in Organic Chemistry, 2018, Vol. 15, No. 1
Beyki and Fallah-Mehrjardi
[14]
[15]
Hikawa, H.; Ino, Y.; Suzuki, H.; Yokoyama, Y. J. Org. Chem.,
2012, 77, 7046-7051.
products in 82-96% yield. All of the 2,3-dihydroquinazolin-
4(1H)-ones are known and were identified by comparison of
their physical and spectroscopic data (IR, NMR) with those
of authentic samples [21-37].
Niknam, K.; Jafarpour, N.; Niknam, E. Chin. Chem. Lett., 2011, 22,
69-72.
[16]
[17]
Khaksar, S.; Talesh, S.M. C.R. Chim., 2012, 15, 779-783.
Wu, J.; Du, X.; Ma, J.; Zhang, Y.; Shi, Q.; Luo, L.; Song, B.; Yang,
S.; Hu, D. Green Chem., 2014, 16, 3210-3217.
Chen, J.; Wu, D.; He, F.; Liu, M.; Wua, H.; Ding, J.; Su, W. Tetra-
hedron Lett., 2008, 49, 3814-3818.
CONCLUSION
[18]
[19]
[20]
In conclusion, Fe3O4@SiO2-SO3H nanoparticles has
proved to be a highly efficient solid acid catalyst for the cy-
clocondensation reaction between aldehydes and ketones
with anthranilamide under solvent-free conditions at room
temperature. This procedure offers several advantages in-
cluding mild reaction conditions, short reaction times, clean
reaction profiles, ease of work-up, environmentally benign,
recyclability and reusability of the catalyst, and high product
yields, which makes it a useful, easy, mild, efficient and
general method for the synthesis of 2,3-dihydroquinazolin-
4(1H)-ones.
Shi, D.; Rong, L.; Wang, J.; Zhuang, Q.; Wang, X.; Hu, H. Tetra-
hedron Lett., 2003, 44, 3199-3201.
Li, S.W.; Nair, M.G.; Edwards, D.M.; Kisliuk, R.L.; Gaumont, Y.;
Dev, I.K.; Duch, D.S. Humphreys, J.; Smith, G.K.; Ferone, R. J.
Med. Chem., 1991, 34, 2746-2754.
[21]
[22]
[23]
[24]
[25]
[26]
[27]
Chen, J.X.; Wu, H.Y.; Su, W.K. Chin. Chem. Lett., 2007, 18, 536-
538.
Shaabani, A.; Maleki, A.; Mofakham, H. Synth. Commun., 2008,
38, 3751-3759.
Zong, Y.X.; Zhao, Y.; Luo, W.C.; Yu, X.H.; Wang, J.K.; Pan, Y.
Chin. Chem. Lett., 2010, 21, 778-781.
Zhang, Z.-H.; Lu, H.-Y.; Yang, S.H.; Gao, J.-W. J. Comb. Chem.,
2010, 12, 643-646.
Wang, M.; Zhang, T.T.; Liang, Y.; Gao, J.J. Chin. Chem. Lett.,
2011, 22, 1423-1426.
CONSENT FOR PUBLICATION
Abdollahi-Alibeik, M.; Shabani, E. Chin. Chem. Lett., 2011, 22,
1163-1166.
Not applicable.
Murthy, P.V.N.S.; Rambabu, D.; Krishna, G.R.; Reddy, C.M.;
Prasad, K.R.S.; Rao, M.V.B.; Pal, M. Tetrahedron Lett., 2012, 53,
863-867.
CONFLICT OF INTEREST
[28]
Rambabu, D.; Kumar, K.; Sreenivas, B.Y.; Sandra, S.; Kandale, A.;
Misra, P.; Rao, B.M.V.; Pal, M. Tetrahedron Lett., 2013, 54, 495-
501.
The authors declare no conflict of interest, financial or
otherwise.
[29]
[30]
[31]
Labade, V.B.; Shinde, P.V.; Shingare, M.S. Tetrahedron Lett.,
2013, 54, 5778-5780.
ACKNOWLEDGEMENTS
Safaei, H.R.; Shekouhy, M.; Shafiee, V.; Davoodi, M. J. Mol. Liq.,
2013, 180, 139-144.
We gratefully acknowledge the support of this work by
Payame Noor University (PNU).
Chen, R.; Guo, T.; Zhang-Negrerie, D.; Du, Y.; Zhao, K. Synthesis,
2013, 45, 2998-3006.
[32]
[33]
Revathy, K.; Lalitha, A. J. Iran. Chem. Soc., 2015, 12, 2045-2049.
Wang, J.; Zong, Y.; Fu, R.; Niu, Y.; Yue, G.; Quan, Z.; Wang, X.;
Pan, Y. Ultrason. Sonochem., 2014, 21, 29-34.
Safari, J.; Gandomi-Ravandi, S. J. Mol. Catal. A: Chem., 2014,
390, 1-6.
REFERENCES
[1]
[2]
[3]
[4]
Varma, R.S. Green Chem., 1999, 1, 43-55.
[34]
[35]
[36]
[37]
Tanaka, K.; Toda, F. Chem. Rev., 2000, 100, 1025-1074.
Singh, M.S.; Chowdhury, S. RSC Adv., 2012, 2, 4547-4592.
Rostami, A.; Pourshiani, O.; Gheisarzade, S. Lett. Org. Chem.,
2016, 13, 201-205.
Abdollahi-Alibeik, M.; Shabani, E. J. Iran. Chem. Soc., 2014, 11,
351-359.
Shang, Y.-H.; Fan, L.-Y.; Li, X.-X.; Liu, M.-X. Chin. Chem. Lett.,
2015, 26, 1355-1358.
[5]
[6]
Khalafi-Nezhad, A.; Mohammadi, S. ACS Comb. Sci., 2013, 15,
512-518.
Mekala, R.; Madhubabu, M.V.; Dhanunjaya, G.; Regati, S.;
Chandrasekhar, K.B.; Sarva, J. Synth. Commun., 2017, 47, 121-
130.
Ghafuri, H.; Rashidizadeh, A.; Ghorbani, B.; Talebi, M. New J.
Chem., 2015, 39, 4821-4829.
[7]
[8]
Sobhani, S.; Pakdin-Parizi, Z. RSC Adv., 2014, 4, 13071-13077.
Connolly, D.J.; Cusack, D.; Sullivan, T.P.O.; Guiry, P.J. Tetrahe-
dron, 2005, 61, 10153-10202.
[38]
[39]
Nemati, F.; Heravi, M.M.; Saeedi, R.R. Chin. J. Catal., 2012, 33,
1825-1831.
Kiasat, A.R.; Davarpanah, J. J. Mol. Catal. A: Chem., 2013, 373,
46-54.
[9]
Marzaro, G.; Guiotto, A.; Pastorini, G.; Chilin, A. Tetrahedron,
2010, 66, 962-968.
[40]
[41]
Naeimi, H.; Nazifi, Z.S. J. Nanopart. Res., 2013, 15, 2026-2037.
Khorshidi, A.; Shariati, S.; Aboutalebi, M.; Mardazad, N. Iran.
Chem. Commun., 2016, 4, 142-145.
[10]
[11]
Bakavoli, M.; Sabzevari, O.; Rahimizadeh, M. Chin. Chem. Lett.,
2007, 18, 1466-1468.
Naleway, J.J.; Fox, C.M.J.; Robinhold, D.; Terpetsching, E.; Olsen,
N.A.; Haugland, R.P. Tetrahedron Lett., 1994, 35, 8569-8572.
Mhaske, S.B.; Argade, N.P. Tetrahedron, 2006, 62, 9787-9826.
Horton, D.A.; Bourne, G.T.; Smythe, M.L. Chem. Rev., 2003, 103,
893-930.
[42]
[43]
Gao, L.; Ji, H.; Rong, L.; Tang, D.; Zha, Y.; Shi, Y.; Tu, S. J. Het-
erocyclic Chem., 2011, 48, 957-960.
[12]
[13]
Somasekhara, S.; Dighe, V.S.; Mukherjee, S.L. Curr. Sci., 1964,
33, 645-646.
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