Cascade embedding triethyltryptophanium iodide ionic liquid (TrpEt3+I?) on silicated titanomagnetite core (Fe3-xTixO4-SiO2@TrpEt3+I?): A novel nano organic–inorganic hybrid to prepare a library of 4-substituted quinoline-2-carboxylates and 4,6-disubstituted quinoline-2-carboxylates

Article abstract of DOI:10.1002/jccs.202000444

A library of substituted quinolone-2-carboxylates (4,6-disubstituted quinolone-2-carboxylates, 6-substituted quinoline dialkyl-2,4-dicarboxylates, and 6-substituted 4-[2-methoxy-2-oxoethyl]quinoline-2-methylcarboxylates) was obtained through different scopes of one-pot and one-step MCRs such as (a) three-component reaction of aromatic amines, dialkyl acetylenedicarboxylates, and terminal alkenes/ketones; (b) pseudo three-component reaction of anilines and dialkyl acetylenedicarboxylates; and (c) pseudo three-component reaction of anilines and methyl propiolate under solvent-free conditions at 100°C. The promoter of these annulation processes is a novel inorganic–organic core–shell that was obtained from silicated titanomagnetite, tryptophan amino acid, and ethyl iodide. The tryptophan embedded on the silicated titanomagnetite core (Fe_3-xTi_xO₄-SiO₂) followed by alkylation with ethyl iodide subsequently result in in situ preparation of triethyltryptophanium iodide ionic liquid (TrpEt₃⁺I^?). The final nanohybrid (Fe_3-xTi_xO₄-SiO₂@TrpEt₃⁺I^?) was characterized by field-emission scanning electron microscope, EDAX, FT-IR, TGA/DTG, vibrating sample magnetometer, and X-ray fluorescence techniques. The highlighted features of the protocol are as follows: (a) synthesis of a vast range of substituted quinolines through a straightforward method from simple substrates under solvent-free conditions, (b) utilizing various scopes of functionalities as substrates, (c) simple separation of the nano promoter via an external magnet, (d) regioselectivity in the cascade annulation procedure, and (e) recovery and reusability of the nanocomposite within three runs without significant activity loss.

Full text of DOI:10.1002/jccs.202000444

Received: 6 October 2020
Revised: 26 March 2021
Accepted: 13 April 2021
DOI: 10.1002/jccs.202000444
A R T I C L E
Cascade embedding triethyltryptophanium iodide ionic
+
À
liquid (TrpEt I ) on silicated titanomagnetite core
3
+
À
(
Fe Ti O -SiO @TrpEt I ): A novel nano organic–
3
-x x 4
2
3
inorganic hybrid to prepare a library of 4-substituted
quinoline-2-carboxylates and 4,6-disubstituted quinoline-
2-carboxylates
Kobra Nikoofar
| Fatemeh Molaei Yielzoleh
Department of Chemistry, Faculty of
Physics and Chemistry, Alzahra
University, Tehran, Iran
Abstract
A library of substituted quinolone-2-carboxylates (4,6-disubstituted quinolone-2-car-
boxylates, 6-substituted quinoline dialkyl-2,4-dicarboxylates, and 6-substituted 4-[2-
methoxy-2-oxoethyl]quinoline-2-methylcarboxylates) was obtained through differ-
ent scopes of one-pot and one-step MCRs such as (a) three-component reaction of
aromatic amines, dialkyl acetylenedicarboxylates, and terminal alkenes/
ketones; (b) pseudo three-component reaction of anilines and dialkyl
acetylenedicarboxylates; and (c) pseudo three-component reaction of anilines and
Correspondence
Kobra Nikoofar, Department of
Chemistry, Faculty of Physics &
Chemistry, Alzahra University, Tehran,
Iran.
Email: k.nikoofar@alzahra.ac.ir;
kobranikoofar@yahoo.com
ꢀ
methyl propiolate under solvent-free conditions at 100 C. The promoter of these
Funding information
Alzahra University
annulation processes is a novel inorganic–organic core–shell that was obtained
from silicated titanomagnetite, tryptophan amino acid, and ethyl iodide. The trypto-
phan embedded on the silicated titanomagnetite core (Fe Ti O -SiO ) followed by
3-x
x
4
2
alkylation with ethyl iodide subsequently result in in situ preparation of
+
3
À
triethyltryptophanium iodide ionic liquid (TrpEt I ). The final nanohybrid
+
À
(
Fe Ti O -SiO @TrpEt I ) was characterized by field-emission scanning electron
3-x x 4 2 3
microscope, EDAX, FT-IR, TGA/DTG, vibrating sample magnetometer, and X-ray
fluorescence techniques. The highlighted features of the protocol are as follows:
(a) synthesis of a vast range of substituted quinolines through a straightforward
method from simple substrates under solvent-free conditions, (b) utilizing various
scopes of functionalities as substrates, (c) simple separation of the nano promoter
via an external magnet, (d) regioselectivity in the cascade annulation procedure,
and (e) recovery and reusability of the nanocomposite within three runs without
significant activity loss.
K E Y W O R D S
+
À
2
,4-disubstituted quinolines, annulation, ionic liquid, nano Fe3-xTi
x 4 2 3
O -SiO @TrpEt I ,
titanomagnetite, tryptophan
J Chin Chem Soc. 2021;1–14.
http://www.jccs.wiley-vch.de
© 2021 The Chemical Society Located in Taipei & Wiley-VCH GmbH.
1

2
NIKOOFAR AND MOLAEI YIELZOLEH
[
34]
1
| INTRODUCTION
[b]pyrans, and dihydropyrano[2,3-c]pyrazoles synthesis,
[
35,36]
hexahydroquinolines,
and 2,3-dihydroquinazolin-4
[
37]
Quinoline (benzo[b]pyridine or 1-azanaphthalene) is an
applicant of N-containing heterocyclic motif in chemistry,
medicine, and biology. Various kinds of compounds bearing
quinolone building-blocks demonstrated numerous proper-
ties such as antitumor, anti-inflammatory, antiviral,
antimalarial, antifungal, antibacterial, anticancer,
(1H)-ones.
Ionic liquids (ILs) are organic/inorganic salts with a
melting point often below 100 C, low vapor pressure, low
toxicity, high ion density and ionic conductivity, high
chemical stabilities, and nonflammability. ILs possess
wide-spread availability through changeable cations and
anions that play dual crucial role in organic chemistry as
ꢀ
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
antipsychotic, anti-HIV, antituberculosis, and antiox-
idant
[11]
[38–40]
activities. In addition, various quinolone-
exclusive catalyst/reaction media.
containing compounds, applied in several branches of
science and technology, exhibited interesting properties
Amino acid ionic liquids (AAILs) were utilized
recently in many aspects of scientific and technological
[
12]
[41]
[42]
like electrochemical and antiplasmodium properties,
fields as lubricants,
exchange chiral separations,
self-assembly media of amphiphiles.
metal Scavenging,
ligand-
[
13]
[14]
[43]
[44]
fluorescence and cell imaging,
optoelectronic,
and
CO absorbants,
and
2
[45]
[
15]
rubber chemicals.
,4-Substuittied quinolines prepared via several
The catalytic effi-
2
cacy of some AAILs observed in the Morita–Baylis–
[46] [47]
methods such as cascade annulation of anilines with
Hillman reaction,
Knoevenagel condensation,
[
48]
alkyne esters in a 1:2 M ratio in the presence of Cu(OTf) /
thiol-Michael addition,
and Baeyer–Villiger oxidation
2
[
16]
[49]
HOTf, iron-catalyzed intermolecular [4 + 2] cyclization
of cyclic ketones.
[
17]
of arylnitrones with geminal-substituted vinyl acetates,
A -coupling between an aldehyde, amine, and alkyne,
In following our research preference to design novel
nanostructures and investigation of their catalytic activity
[
18]
3
[
50–54]
silver-catalyzed [3 + 1 + 2] annulation of simple amines,
in heterocycles synthesis,
herein, we report a novel
[19]
alkyne esters and terminal alkynes,
DDQ-promoted
multi-layered inorganic–organic hybrid gained from
three-component reaction of o-amino arylketones, alde-
silicated titanomagnetite, tryptophan amino acid, and
[
20]
+ À
hydes, and ammonium acetate,
Cu(OAc) ÁH O cata-
ethyl iodide (nano Fe Ti O -SiO @TrpEt I ). In fact,
2
2
3-x
x
4
2
3
lyzed domino reaction of primary arylamines and terminal
the shell is an AAIL obtained in situ from tryptophan and
ethyl iodide that anchored into the silica-titanomagnetized
core step by step. The catalytic efficiency of the inorganic–
bioorganic composite is examined in the solvent-free
regioselective cascade annulations to prepare a library of
substituted quinolones, which are as follows: (a) 4,-
6-disubstituted quinoline-2-carboxylates via the three-
component reaction of aromatic amines, dialkyl
acetylenedicarboxylates, and terminal alkenes/ketones;
(b) 6-substituted quinoline dialkyl-2,4-dicarboxylates
through the pseudo three-component reaction of anilines
and dialkyl acetylenedicarboxylates; and (c) 6-substituted
4-(2-methoxy-2-oxoethyl)quinoline-2-methylcarboxylates)
by pseudo three-component reaction of anilines and
[21]
alkynes in a 1:2 M ratio,
and multicomponent reaction
of aniline, 2-nitro benzaldehyde, and propargyl alcohol in
[22]
the presence of copper bromide.
Magnetic nanoparticles attracted special attention
based on their unique properties and exploited in various
scopes including multimodal photoacoustic, photothermal
[
23]
and photomechanical contrast agents,
cancer
[
24]
[25]
nanotheranostic,
antimicrobial drug delivery,
[
26]
electrochemical sensing,
and magnetic resonance
[
27]
imaging.
Recently, the well-known magnetite (Fe O ) is utilized
3
4
[
28]
in many catalytic fields such as wastewater treatment,
Fenton-like degradation of tetracycline (as an organic
[29]
[30]
ꢀ
pollutant),
upgrading of heavy oil,
and organic syn-
methyl propiolate at 100 C (Scheme 1).
[
31]
thesis. The significance of nanomagnetite in the organic
synthesis progressing area attributed to its easy production
procedure, high functionalization capacity, large surface
area, good stability, low toxicity and cost, simple isolation
from the reaction media through an external magnet, and
great recoverability and reusability without decreasing
activity.
2 | RESULTS AND DISCUSSION
2.1 | Characterization of the
nanocatalyst
Titanomagnetite (Fe3-xTi O ) is an interesting magne-
The schematic preparing procedure of nano Fe Ti O -
x
4
3-x
x 4
+
À
tized species, which is the objective in decolorization of
SiO @TrpEt3
I
is illustrated in Scheme 2. In the first
2
[32]
methylene blue.
In addition, many catalytic systems
step, titanomagnetite was prepared from titanium tetra-
chloride and ferrous sulfate heptahydrate, subsequent by
the reaction with tetraethyl orthosilicate (TEOS) to
obtain nano Fe3-xTi O -SiO . In order to seat the novel IL
were prepared based on titanomagnetite to promote dif-
ferent kinds of organic transformations like synthesis of
[33]
dihydropyrano[3,2-c]chromen-2-ones,
tetrahydrobenzo
x
4
2

NIKOOFAR AND MOLAEI YIELZOLEH
3
+
À
x 4 2 3
SCHEME 1 Preparation of a library of substituted quinolines in the presence of nano Fe3-xTi O -SiO @TrpEt I
+
À
x 4 2 3
SCHEME 2 Schematic preparation procedure of nano Fe3-xTi O -SiO @TrpEt I
+
À
À1
teriethyl trypthophanium iodide (TrpEt3 I ) on this core,
a tandem two-step process was performed. Firstly, the
amino acid tryptophan was embedded followed by
adding ethyl iodide to yield the final silica coated
titanomagnetite-IL nanocomposite (nano Fe3-xTi O -
1,214 cm (stretching vibration of Si O Si group) affi-
rmed the presence of silica layer on the titanomagnetite
core. The stretching vibration of silanol of silica
À1
(3,419 cm ) was covered with the O H bonds of the
Fe3-xTi O . The observations in Figure 1c showed the
x
4
x 4
+
À
SiO @TrpEt3 I ). The IL part is also obtained separately
and characterized with physical and spectral data
expressed in Section 3.3.
peaks for bending vibrations of the N H bond at 1,555
and 846 cm , in addition to the bands of stretching
vibration of the NH3 group at 2,736–3,053 cm . The
bands at 1,662 cm
(C C bond), and 1,251 cm (C N bond) confirmed the
presence of tryptophan. Finally, Figure 1d contains all
the bands of the previous layers in addition to the ethyl
iodide part that covered themselves completely made the
bands very broad.
2
À1
+
À1
À1
À1
The FTIR spectra for successive preparation of the
(C O esteric band), 1,488 cm
+
À
À1
nanocomposite Fe3-xTi O -SiO @TrpEt I
3
are illus-
x
4
2
trated in Figure 1. According to Figure 1a, the bond at
À1
5
88, 736, and 3,419 cm
attributed to symmetric
stretching vibrations of Fe O, Ti O, and O H bonds,
respectively. In Figure 1b, appearance of the bands at

4
NIKOOFAR AND MOLAEI YIELZOLEH
100
0.0000
-
-
-
-
-
0.0002
0.0004
0.0006
0.0008
0.0010
98
96
94
92
90
88
86
DTG
-0.0012
-0.0014
-0.0016
-0.0018
TGA
x 4 x 4
FIGURE 1 The FT-IR spectra of (a) Fe3-xTi O , (b) Fe3-xTi O -
200
400
600
800
SiO
SiO
2
, (c) Fe3-xTi
x
À
O
4
-SiO
2
@Trp, and (d) nano Fe3-xTi
x
O
4
-
Temperature (°C)
+
2
3
@TrpEt I
x 4 2
FIGURE 2 TGA/DTG curves of nano Fe3-xTi O -SiO @Trp
+
À
(
x 4 2 3
top) and nano Fe3-xTi O -SiO @TrpEt I (bottom)
The thermal stability of the nano Fe3-xTi O -
x
4
SiO @Trp (Figure 2, top) and the final Fe Ti O -
The field-emission scanning electron microscope
(FESEM) image of the synthesized Fe Ti O -
2
3-x
x
4
+
À
SiO @TrpEt3 I nanocomposite (Figure 2, down) were
2
3-x
x 4
+
À
investigated by thermogravimetric analysis. The top
SiO @TrpEt I
nanocomposite is demonstrated in
2
3
ꢀ
curve shows initial low mass loss of about 6.2% at 91 C
Figure 3. The average diameter of the nanoparticles is
between 10 and 24 nm, with approximately uniform spheri-
cal shape.
that may be due to outer organic layer decomposition
(
1
4
Trp). Consequential weight loss of about 9.8% at
ꢀ
ꢀ
ꢀ
94 C, 12.89% at 276 C, 14.56% at 379 C, 6.57% at
The results of energy-dispersive X-ray spectroscopy
ꢀ
ꢀ
+ À
(EDX) of the nano Fe3-xTi O -SiO @TrpEt I
3
48 C, and 10.73% at 751 C were also observed. The
are
x
4
2
bottom diagram that related to the final Fe Ti O -
shown in Figure 4. The data affirmed the presence of
Fe (12.68%), Ti (16.20%), Si (13.55%), O (45.36%), C
(3.71%), N (2.90%), and I (1.67%) that approved suc-
cessful synthesis of the nanohybrid. The element Na
(1.6%) is due to the sodium hydroxide and sodium
nitrate utilized in the synthetic procedure of the nano
composite.
3-x
x 4
+
À
SiO @TrpEt I nanostructure deconstructed very low
2
3
ꢀ
mass loss of about 4.69% at 90 C, which probably related
to the release of very slight organic outer part. Then, the
nanostructure displays a weight loss of about 1.76% at
ꢀ
ꢀ
ꢀ
ꢀ
1
65 C, 2.85% at 340 C, 1.21% at 515 C, 0.85% at 590 C,
ꢀ
and 1.9% above 800 C. According the thermal decomposi-
tion, the Fe Ti O -SiO @ TrpEt I nanohybrid is
approximately stable until 800 C with the total weight
loss of about 13.26%. The comparison of the thermal
behavior of Fe3 Ti O -SiO @Trp (top) and Fe Ti O -
+
À
The vibrating sample magnetometer (VSM) analysis of
the sequential nanocomposite preparation gained in Figure 5
is used to investigate its magnetite behavior. According to
the curves a–d, saturation magnetization of 26.091 emu/g for
Fe Ti O , 25.905 emu/g for Fe Ti O -SiO 19.976 emu/g
3-x
x
4
2
3
ꢀ
-x
À
x
4
2
3-x
x
4
+
SiO @TrpEt3 I (down) affirmed that embedding ethyl
2
3-x
x
4
3-x
x
4
2,
iodide on the inner surface of the Fe3 Ti O -SiO @Trp
for Fe Ti O -SiO @Trp, and 18.044 emu/g for Fe Ti O -
SiO @TrpEt I confirmed the total superparamagnetism
2 3
-x
À
x
4
2
3-x
x
4
+ À
2
3-x
x 4
+
that causes preparation of TrpEt3
I
IL elevates the
thermal stability of the whole nanohybrid.
properties. The descending slope in the values related to

NIKOOFAR AND MOLAEI YIELZOLEH
5
+
À
x 4 2 3
FIGURE 3 FESEM images of Fe3-xTi O -SiO @TrpEt I nanocomposite
embedding silica, tryptophan, and ethyl iodide on the inter-
nal Fe Ti O core.
structure of the Fe3-xTi O during the synthesis of the
nanocomposite.
x
4
3-x
x 4
X-ray fluorescence (XRF) analysis of the titano-
magnetite
core
I
and
the
final
Fe3-xTi O -
x 4
+
À
SiO @TrpEt3
nanocomposite are represented in
2.2 | Investigation of the catalytic
+
2
À
Table 1 (entries 1 and 2, respectively). The Iodine and
SiO exhibition along with Fe O and TiO affirmed suc-
activity of Fe Ti O -SiO @TrpEt I in
3-x x 4 2 3
the synthesis of disubstituted quinolone-
2-carboxylates library
2
2
3
2
+
À
cessful preparation of Fe3-xTi O -SiO @TrpEt I
3
x
4
2
through step-by-step embedding procedure on the initial
Fe3-xTi O core. In addition, the comparison of the per-
Initially, to investigate the catalytic efficacy of Fe Ti O -
x
4
3-x
x 4
+
À
centages of TiO and Fe O in the initial core and final
SiO @TrpEt3 I nanocomposite, the reactions of aniline
2
2
3
2
nanocomposite (entries 1 and 2) affirmed the invariable
(1a, 1 mmol), DMAD (2a, 1 mmol), and phenylacetylene

6
NIKOOFAR AND MOLAEI YIELZOLEH
attempt, the model reaction was performed in the
absence of solvent at different temperatures (80, 100, and
ꢀ
1
20 C) and also catalyst amount (entries 6–12). The
ꢀ
results demonstrated that doing the reaction at 100 C in
+
À
the presence of nano Fe3-xTi O -SiO @TrpEt I (0.12 g)
x
4
2
3
under solvent-free conditions is the best choice (entry
ꢀ
1
1). The reaction was examined at 120 C but no yield ele-
vation was observed (entry 12). In order to discover more
accurate reaction period, the model reaction was
repeated in the presence of nano Fe Ti O -SiO @
3
-x
x
4
2
+
À
TrpEt3
I
(0.12 g) under solvent-free conditions at
ꢀ
1
00 C. The results affirmed that the reaction progress
occurred up to 18 hr from the beginning and time dura-
tion up to 24 does not affect the reaction promotion. In
order to recognize the crucial role of nanostructure in the
reaction progress, the model reaction was examined in
+
À
x 4 2 3
FIGURE 4 EDX analysis of nano Fe3-xTi O -SiO @TrpEt I
+
À
the absence of nano Fe3 Ti O -SiO @ TrpEt I
at
00 C within 24 hr. The result demonstrated very low
-x
x
4
2
3
ꢀ
1
yield (entry 13). In another attempt, the model reaction
was examined in the presence of nano Fe3 Ti O -SiO @
-x
x
4
2
ꢀ
Trp (0.12 g) at 100 C within 24 hr period. The results
showed the reaction progress with 58% yield. The obser-
vation affirmed the catalytic role of the IL part in the
+
À
Fe3-xTi O -SiO @ TrpEt I
3
nanocomposite to elevate
x
4
2
the reaction yield. Finally, the optimal conditions were
identified in the presence of nano Fe Ti O -SiO @
3
-x
x
4
2
ꢀ
+
À
TrpEt3 I (0.12 g) under solvent-free conditions at 100 C
entry 11).
To spread the efficiency of the route, the reaction of dif-
ferent anilines 1a–g with dialkyl acetylenedicarboxylates
a, b, and terminal alkynes 3a, b examined under opti-
(
2
mized conditions. The results are summarized in Table 3.
Various kinds of substituted quinoline-2-carboxylates were
obtained via the reaction of anilines and its derivatives with
DMAD 2a and phenylacetylene 3a successfully (5a–d).
FIGURE 5 VSM magnetization curves of (a) Fe3-xTi
b) Fe3-xTi -SiO , (c) Fe3-xTi -SiO @Trp,and (d) Fe3-xTi
SiO @TrpEt
x 4
O
(
x
O
4
+
2
x
O
4
2
x 4
O -
À
2
3
I
1-Butyne 3b, as an aliphatic acetylenic candidate, per-
formed the reaction very well with aniline/DMAD and
4-hydroxyaniline/DEAD to gain the correspon-
ding quinolines 5e and 5f, respectively. Applying
x 4
TABLE 1 XRF analysis results of the Fe3-xTi O core and the
+
À
final nano Fe3-xTi
x
O
4
2 3
-SiO @TrpEt I
Fe
2
O
3
TiO
2
SiO
2
I
LOI
11.79
7.95
Entry
1-naphthylamine in this transformation did not reach sat-
(
%)
%)
46.595
47.779
37.462
37.208
—
—
1
2
isfactory results and the product methyl 4-phenylbenzo[h]
quinoline-2-carboxylate 5g was obtained with 36% yield.
Although different aniline derivatives eventuated properly,
but in the case of 4-methoxyaniline the yield was few to
obtain the product 5h. Among the eight various quinolines
obtained in this scope, two of them are the new com-
pounds (5e and 5f) that are completely characterized by
physical and spectral data.
In the next stage, to extend the scope of substituted
quinoline-2-carboxylates synthesis, the reaction of ani-
lines 1 with dialkyl acetylenedicarboxylates 2a, b, and
acetophenones 4a–d was examined (Table 4). The results
demonstrated that acetophenone and its derivatives
(
8.069
0.055
(
3a, 1.2 mmol) were applied as the model. According to
the results in Table 2, various conditions (catalyst
amount, reaction media, and temperature) were exam-
ined to obtain the optimized situation. The solvent effect
screened by various solvents such as MeOH, EtOH,
CH CN, and toluene (entries 1–5) and the data affirmed
3
that none of them are appropriate. In the case of entries
3
and 4, no products were observed and the substrates
remained intact after the reaction period. In the next

NIKOOFAR AND MOLAEI YIELZOLEH
7
a
TABLE 2 Screening the reaction conditions to prepare methyl 4-phenylquinoline-2-carboxylate 5a
+
À
ꢀ
b
Entry
Nano Fe3-xTi
0.04
x
O
4
-SiO
2
@TrpEt
3
I
(g)
Solvent (5 ml)
MeOH
Temp ( C)
120
120
120
120
100
80
Yield (%)
1
2
3
4
5
6
7
8
9
34
38
—
—
18
27
62
43
57
45
73
75
10
0.08
MeOH
0.08
EtOH
0.08
3
CH CN
0.08
Toluene
—
0.04
0.08
—
100
80
0.1
—
0.1
—
100
80
1
1
1
1
0
1
2
3
0.12
—
0.12
—
100
120
100
0.12
—
—
—
a
The substrates 1a:2a:3a were used in 1:1:1.2 molar ratio in 24 hr period.
b
Isolated yields.
TABLE 3 Synthesis of substituted
quinoline-2-carboxylates 5a–h from
three-component reaction of anilines
1
2
a–g, dialkyl acetylenedicarboxylates
a, b, and terminal alkynes 3a, b
a
ac
5bc
5cc
5dc
5
1
8 h, 73%b
18 h, 65%
20 h,71%
20 h, 84%
5
e (new)
5f (new)
5gc
5hc
1
8 h, 75%
15 h, 92%
22 h, 36%
18 h, 12%
a
+ À
Reaction conditions: 1 (1 mmol), 2 (1 mmol), 3 (1.2 mmol), nano Fe3-xTi
x
O
4
-SiO
2
@TrpEt
3
I
(0.12 g)
ꢀ
at 100 C.
b
Isolated yields.
c
Reference of the known compounds is 19.
accomplished the reaction successfully to obtain the cor-
In continuation to vast quinolines library synthesis,
the pseudo three-component reaction of anilines 1 with
dialkyl acetylenedicarboxylates 2a, b was investigated
(Table 5). According to the data, aniline and its para-
substituted derivatives reacted with DMAD 2a to obtain
respondence products 5a, and 5i–l. In the case of
4
-methoxyacetophenone, the reaction progressed in very
low yield to obtain the methyl 4-(4-methoxyphenyl)quin-
oline-2-carboxylate 5l with 13%. The compounds 5j and
5
k are the new ones that are characterized completely in
the
desired
6-substituted
quinoline
dialkyl-2,-
the experimental section. It must be mentioned that the
4-dicarboxylates 5l–r. 2-Nitroaniline also achieved the
regioselective transformation to afford dimethyl
8-nitroquinoline-2,4-dicarboxylate 5q. Utilizing DEAD
2b, as another acetylene ester candidate, generated the
corresponding product 5r in moderate yield.
reaction examined via A -coupling in the presence of
3
benzaldehyde instead of acetophenone in identical condi-
tions within a 24 hr period but no quinoline products
were observed.

8
NIKOOFAR AND MOLAEI YIELZOLEH
TABLE 4 Synthesis of 4-substituted
quinoline-2-carboxylates 5 from the
reaction of anilines, dialkyl
acetylenedicarboxylates 2, and
a
acetophenones 4
5
ac
9 h, 63%b
5ic
5j (new)
5kc
1
22h, 56%
10 h, 77%
20 h, 13%
a
+ À
Reaction conditions: 1 (1 mmol), 2 (1 mmol), 4 (1.2 mmol), nano Fe3-xTi
x
O
4
-SiO
2
@TrpEt
3
I
(0.12 g)
ꢀ
at 100 C.
b
Isolated yields.
c
Reference of the known compounds is 16.
TABLE 5 Synthesis of 6-substituted
quinoline dialkyl-2,4-dicarboxylates 5l–
r from the reaction of anilines 1, and
a
dialkyl acetylenedicarboxylates 2
5
lc
0 h, 91%
5mc
5nc
5oc
20 h,90%b
2
20 h, 84%
20 h, 83%
5
pc
0 h,85%
5q (new)
22 h, 82%
5rc
2
21 h, 51%
a
+ À
ꢀ
Reaction conditions: 1 (1.0 mmol), 2 (2.2 mmol), and nano Fe3-xTi
x
O
4
-SiO
2
@TrpEt
3
I
(0.12 g) at 100 C.
b
Isolated yields.
c
Reference of the known compounds is 16.
TABLE 6 Synthesis of 6-substituted
4
2
-(2-methoxy-2-oxoethyl)quinoline-
-methylcarboxylates 5t–5y from the
reaction of anilines, and methyl
a
propiolate 6
5
sc
h, 91%b
5t (new)
5uc
5
7 h, 91%
5 h, 89%
5
vc
h, 95%
5w (new)
5xc
4
5 h, 74%
4 h, 81%
a
+ À
ꢀ
Reaction conditions: 1 (0.4 mmol), 6 (1.2 mmol), and nano Fe3-xTi
x
O
4
-SiO
2
@TrpEt
3
I
(0.12 g) at 100 C.
b
Isolated yields.
c
Reference of the known compounds is 21.
In order to extend the diversity of the substituted
quinoline preparation, the reaction of anilines 1 and
methyl propiolate 6 was performed to obtain the
desired 6-substituted 4-(2-methoxy-2-oxoethyl)quinoline-
2-methylcarboxylates 5t–5y (Table 6). Aniline and its
para-substituted derivative accomplished the reaction
well (5t–w). The yield in 4-methoxyaniline usage was
moderate in comparison to the other substituents (5x).

NIKOOFAR AND MOLAEI YIELZOLEH
9
SCHEME 3 Mechanism for
the synthesis of 2,4-disubstituted
quinolines
1
-Naphthylamine, as a sterically hindered candidate,
In the next part, a comparative study of our protocol
with previously reported methods is illustrated in Scheme 4.
As could be seen, the most highlighted feature of this proto-
col is performing the reactions in the absence of any addi-
tive such as HOTf and Na S O . This accomplishment
gave good results to obtain 5y.
Although the reaction mechanism is not clear
completely, a plausible route is proposed in Scheme 3. First,
enamine A is produced via nucleophilic attack of amine
group 1 to dialkyl acetylenedicarboxylates 2, which isomer-
ized to enamine B. The interaction of terminal alkyne 3 with
2
2 8
affirms the elevated activity of the nano Fe Ti O -
3
-x
x 4
+
3
À
SiO @TrpEt I core–shell. This phenomenon could be
2
+
3
À
nano Fe Ti O -SiO @TrpEt I formed the activated
according to the synergic effect of each layer utilized in its
structure, which leads to its successful operation in the
absence of additive. It is also noteworthy that the synthesis
of a library of substituted quinolines occurred in the
3-x
x
4
2
alkynyl-catalyst species. Subsequent regioselective inter-
molecular nucleophilic attack of alkynyl-catalyst species to
imine B, generated intimidate C. The propargyl imine
D was established through a C–C bond cleavage and alkyl
acetate removal. Finally, compound D underwent inter-
molecular Freidel–Crafts-type addition leading to annulated
absence of any hazardous solvents such a CH CN or MeOH
3
at more reduced temperatures in comparison to the previ-
ous methods that made the protocol green and economic.
[19]
final product 5.
The highlighted feature of this work is
the preparation of metal-free activated alkynyl-catalyst spe-
cies to progress the reaction.
3 | EXPERIMENTAL
3.1 | General
In the next step, the recovery and reusability of the
+
À
nano Fe3-xTi O -SiO @TrpEt I
were also checked
for the synthesis of methyl-4-phenylquinoline-
x
4
2
3
2
1
-carboxylate 5a through the reaction of aniline (1a,
mmol), DMAD (2a, 1 mmol), and phenylacetylene
All chemicals were purchased from the Aldrich, Merck,
and Alfa-Aesar companies and used without purifica-
tion. Melting points were determined by an Electro-
thermal 9200 apparatus and reported uncorrected. The
FT-IR spectra were gained using KBr disks by a Bruker
FT-IR (Tensor 27) spectrometer. Magnetization proper-
ties were performed by a VSM (MDKB model). Homog-
enization of the nanostructure was performed in a
(
3a, 1.2 mmol). After completion of the reaction based
on the optimized conditions (presence of the 0.12 g of
nanohybrid at 100 C within 18 hr period), methanol
ꢀ
(
10 ml) was added and the nanocatalyst was separated
with an external magnet. Washing with further metha-
nol (2 Â 5 ml), followed by air-drying for 12 hr, and
ꢀ
1
oven drying at 50 C within 3 hr, the recovered catalyst
Wise clean (power of 90 W). H NMR spectra were
was used for another cycle to prepare 5a. The results
recorded through a Bruker drx (300 MHz) spectrometer
in DMSO-d6 solvent. The morphology and size of
the nanocatalyst were estimated by a FESEM (VEGA\
\TESCAN-LMU). Mass spectra were obtained using a
Gc-Mass 5973 network mass-selective detector on a Gc
6690 Agilent device. The EDAX was carried out
through a TESCAN MIRA III machine. Element per-
centages were carried out with Philips-PW2404 XRF
spectrometer. A centrifuge apparatus (UNIVERSAL
320) operating at 5,000–10,000 rpm was used in the
nanocatalyst synthesis procedure.
for three cycles usage demonstrated the high-level cat-
+
À
alytic efficacy of the nano Fe3-xTi O -SiO @TrpEt I
3
x
4
2
to promote the model reaction without significant
activity loss (73, 71, and 68% yields, respectively). The
FESEM images of the recovered and reused nano
+
À
Fe3-xTi O -SiO @TrpEt I are illustrated in Figure 6.
x
4
2
3
The average diameter of nanoparticles is between
0 and 35 nm and the morphology of the nanostruc-
2
ture remained invariable after 3-cycles usage in com-
parison to the initial nanocomposite.

10
NIKOOFAR AND MOLAEI YIELZOLEH
+
À
x 4 2 3
FIGURE 6 FESEM images of the reused nano Fe3-xTi O -SiO @TrpEt I after three runs
[
32]
3
.2 | Synthetic procedure of nano
modification. In a typical modified process, FeSO Á7H O
4
2
+
À
Fe Ti O -SiO @TrpEt I
(3.81 g) was dispersed in deionized water (18 ml). Then, the
aqueous HCl (1 M, 7 ml) was added until reaching pH less
3-x
x
4
2
3
3
.2.1 | Preparation of Fe Ti O
than 1. Next, TiCl (1.6 ml) and hydrazine monohydrate
3-x
x
4
4
(
2 ml) were added dropwise to the reaction mixture. The
ꢀ
The titanomagnetite (Fe Ti O ) was prepared through the
resulting solution was refluxed for 30 min at 90 C
3-x
x 4
previously reported procedure by He group with total
under nitrogen atmosphere. In the next step, a

NIKOOFAR AND MOLAEI YIELZOLEH
11
SCHEME 4 Comparison of the work with the previously reported protocols for the synthesis of substituted quinolines
mixture of NaOH (4 g) and NaNO (2 g) in deionized
was added dropwise into the Fe Ti O solution under vig-
3-x x 4
3
water (18 ml) was added to the reaction mixture and
refluxed for 1 hr under vigorous stirring. Finally, the
mixture was cooled in room temperature and the solid
separated through an external magnet, followed by
washing with water (3 Â 10 ml) and air-drying to
obtain the Fe3 Ti O as black powder.
orous stirring at room temperature, followed by stirring for
20 hr at room temperature. Finally, the product was sepa-
rated by an external magnet, washed with absolute ethanol
ꢀ
(3 Â 5 ml), and dried at 70 C for 5 hr to get Fe Ti O -SiO .
3-x
x
4
2
-x
x
4
3.2.3 | In situ assembling of the
triethyltryptophanium iodide IL
+
À
3
.2.2 | Preparation of Fe Ti O -SiO
(TrpEt I ) on silicated titanomagnetite
3-x
x
4
2
3
core to prepare nano Fe Ti O -
3-x
x 4
+
À
In a flask, nano Fe Ti O powder (1 g) was dispersed in a
SiO @TrpEt I
3-x
x
4
2 3
mixture of ammonia (25 wt%, 2 ml), deionized water
20 ml), and ethanol (60 ml) and sonicated in a bath for
0 min. Next, a mixture of TEOS (0.5 ml) in ethanol (1 ml)
(
3
A mixture of Fe3-xTi O -SiO (1 g) and tryptophan
x 4 2
(0.75 g) in diethyl ether (10 ml) was stirred at room

12
NIKOOFAR AND MOLAEI YIELZOLEH
temperature for 2 hr. Next, chloroform (10 ml) was added
and the solid was separated by centrifugation (15 min),
followed by washing with further chloroform (2 Â 10 ml).
The black powder (Fe Ti O -SiO @Trp) was air-dried for
3.4.1 | Methyl 4-propylquinoline-
2-carboxylate (5e)
ꢀ
À1
Orange solid. Mp: 95–98 C. IR (KBr, cm ): 3,004, 2,955,
3-x
x
4
2
ꢀ
1
2
hr at room temperature and oven-dried at 50 C for 1 hr.
2,922, 2,852, 1,740, 1,646, 1,437. H NMR (300 MHz,
Next, a mixture of the obtained powder (1 g) and ethyl
DMSO-d ): 1.22–1.32 (m, 3H, CH ), 3.40–3.47 (m, 2H,
6
3
iodide (2 g) in 20 ml water/ethanol (1:1) was refluxed at
CH ), 3.57–3.62 (m, 2H, CH ), 3.7 (s, 3H, CH ), 6.90–6.95
2
2
3
ꢀ
9
0 C within 3 hr. The residue was separated through
(m, 1H, Ar), 7.03–7.07 (m, 1H, Ar), 7.14–7.29 (m, 2H, Ar),
13
centrifuging and washing by equimolar water/ethanol solu-
7.75 (d, J = 8.19 Hz, 1H, Ar). C NMR (75 MHz, DMSO-
tion (3 Â 10 ml). The final nano Fe Ti O -
d ): 52.27, 52.70, 119.87, 120.49, 128.54, 129.27, 129.45,
3
-x
x
4
6
+
3
À
ꢀ
+
+
SiO @TrpEt I was obtained by heating at 50 C for 2 hr
161.79, 166.66. MS (ESI) m/z 229 [M ], 214 ([M ]–Me),
2
+ + +
(Scheme 1).
198 ([M ]–OMe), 183 ([M ]–OMe, –Me), 169 ([M ]–
+
OMe, –Et), 155 ([M ]–OMe, –C H ), 59 (CO Me),
3
7
2
4
3 (C H ).
3 7
3
.3 | Synthetic procedure of
triethyltryptophanium iodide IL
+
3
À
(TrpEt I )
3.4.2 | Ethyl 6-hydroxy-
-propylquinoline-2-carboxylate (5f)
4
A mixture of tryptophan (1 g) in ethyl iodide (2.5 g) in
deionized water (10 ml) and ethanol (10 ml) was refluxed
at 90 C for 18 hr. The residue was separated through
ꢀ
À1
Orange solid. Mp: 81–83 C. IR (KBr, cm ): 3,443, 2,923,
ꢀ
1
2,853, 1,740, 1,663, 1,463, 1,020. H NMR (300 MHz,
centrifuging and washing by equimolar water/ethanol
DMSO-d6): 0.88 (t,
(t, J = 7.1 Hz, 3H, CH ), 1.21–1.29 (m, 2H, CH ), 3.84–
3.92 (m, 2H, CH ), 4.14 (q, J = 7.14 Hz, 2H, CH ), 4.39
2 2
(bs, 1H, OH), 6.61–6.68 (m, 1H, Ar), 6.70–6.77 (m, 2H,
Ar), 6.82 (d, J = 8.6 Hz, 1H, Ar). C NMR (75 MHz,
J = 7.05 Hz, 3H, CH3), .1.7
+
À
solution (3 Â 10 ml). The final TrpEt I IL obtained by
3
3
2
ꢀ
heating at 50 C for 2 hr as bright white crystals.
ꢀ
À1
Mp = 270 C. IR (KBr, cm ): 3,404, 3,077, 3,035, 2,852,
13
2
1
,730, 2,561, 1,666, 1,483, 1,455, 1,414, 1,354, 1,249, 1,208,
,007, 966, 920, 803, 862, 527, 505, 424. H NMR
1
DMSO-d ): 13.16, 13.85, 60.29, 61.82, 105.14, 114.91,
6
(
9
7
300 MHz, DMSO-d ): 1.04 (m, 6H, 3CH ), 3.22–3.75 (m,
120.31–122.09, 128.81, 142.93, 146.02, 154.49, 158.35,
6
2
+
+
H, 3CH ), 4.01 (s, 2H, CH ), 9.98–7.04 (m, 2H, Ar),
164.94. MS (ESI) m/z 259 [M ], 242 ([M ]–OH), 226
3
2
+ + +
.36–7.50 (m, 3H, Ar), 7.60 (brs, 1H, NH), 11.05 ((brs, 1H,
([M ]–OH, –Me), 216 ([M ]–C H ), 214 ([M ]–OEt), 198
+ + +
3
7
+
+
OH). MS (ESI) m/z 416 [M ], 401 ([M ]–Me), 358
(
CO H), 202 ([M ]–3Et, –I), 188 ([M ]–NEt , –I), 171
([M ]–OH, –C H ), 170 ([M ]–OEt, –C H ), 152 ([M ]–
3
7
3
7
+
+
+
[M ]–Me,–CO H), 329 ([M ]–3Et), 284 ([M ]–3Et, –
OEt, –C H , –OH), 125 (6-quinolinol).
2
3
7
+
+
2
+
3
+
(
1
[M ]–C H I), 156 (EtI), 143 ([M ]–NEt , –CO H, –I),
3
7
3
2
30 (3-methylindolyl), 44(CO2).
3.5 | General procedures for the
synthesis of 6-substituted quinoline
dialkyl-2,4-dicarboxylates (5l–5r)
3
.4 | General procedure for the synthesis
of 4,6-disubstituted quinolone-
-carboxylates (5a–l)
A mixture of anilines (1, 1 mmol) and dialkyl acetylene-
dicarboxylates (2, 2.2 mmol) in the presence of nano
2
+
3
À
ꢀ
Fe Ti O -SiO @ TrpEt I (0.12 g) were stirred at 100 C
3-x
x
4
2
A mixture of anilines (1a–g, 1 mmol), dialkyl acetylen-
edicarboxylates (2a, b, 1 mmol), and terminal alkynes
until appropriate time monitored by TLC (n-hexane/EtOAc
eluent, 2:1). Next, methanol (10 ml) was added and
the catalyst was separated with an external magnet.
Purification of the products was done through PLC to
obtain the products 5l–5r (Scheme 1b and Table 5).
3
a, b or acetophenones 4a–d (1.2 mmol) in the pres-
+
À
ence of nano Fe3 Ti O -SiO @TrpEt I
3
(0.12 g)
-x
x
4
2
ꢀ
were stirred at 100 C in air. The progress of the reac-
tion was investigated by TLC (n-hexane/EtOAc elu-
ent, 2:1). After completion, methanol (10 ml) was
added to the mixture and the nanocatalyst was sepa-
rated by an external magnet. Purification was
accomplished through plate chromatography on silica
gel to afford the desired products 5a–k (Scheme 1a,
Tables 3 and 4).
3.5.1 | Ethyl 4-(4-bromophenyl)benzo[h]
quinoline-2-carboxylate (5j)
ꢀ
À1
Brown solid. Mp: 84 C. IR (KBr, cm ): 2,982, 2,971,
1
2,855, 1,726, 1,632, 1,466, 1,114, 1,040, 832. H NMR

NIKOOFAR AND MOLAEI YIELZOLEH
13
+
+
+
(
(
300 MHz, DMSO-d ): 1.06–1.22 (m, 2H, CH ), 4.08–4.31
MS (ESI) m/z 338 [M ], 257 ([M ]–Br), 227 ([M ]–Br,
6
2
+
+
m, 3H, CH ), 7.39–7.42 (m, 1H, Ar), 7.44–7.57 (m, 4H,
–OMe), 197 ([M ]–Br, –CO Me), 184 ([M ]–Br, –
CH CO Me), 171 (bromoaniline), 156 (bromophenyl),
89 (CH CH CO Me), 76 (Ph), 73 (CH CO Me),
3
2
Ar), 7.69–7.72 (m 1H, Ar), 7.96 (d, J = 7.56 Hz, 2H, Ar),
8
2
2
13
.06 (d, J = 7.98 Hz, 2H, Ar). C NMR (75 MHz, DMSO-
3
2
2
3
2
d6): 14.82, 61.17, 121.19, 122.55, 124.60, 125.48, 125.73,
59 (CO Me).
2
1
1
26.45, 126.62, 127.03, 128.35, 133.84, 136.29, 143.69,
+
47.49, 159.14, 165.30. MS (ESI) m/z 407 [M ], 326
+
+
+
(
2
[M ]–Br), 311 ([M ]–Br, –Me), 282 ([M ]–Br, –OEt),
3.6.2 | Methyl 6-methoxy-4-(2-methoxy-
2-oxoethyl)quinoline-2-carboxylate (5w)
+
+
55 ([M ]–Br, –CO Et), 205 ([M ]–BrPh, –OEt),
2
1
68 (bromotolyl), 127(naphthyl).
ꢀ
À1
Yellow solid. Mp: 55 C. IR (KBr, cm ): 3,029, 3,002,
2
1
,952, 2,923, 2,851, 1,735, 1,621, 1,512, 1,435, 823. H NMR
3
2
.5.2 | Dimethyl 8-nitroquinoline-
,4-dicarboxylate (5q)
(300 MHz, DMSO-d ): 3.54–3.55 (m, 2H, CH ), 3.62 (s, 3H,
6
2
OCH ), 3.65 (s, 3H, OCH ), 3.7 (s, 3H, OCH ), 6.43 (d,
3
3
3
J = 8.83 Hz, 1H, Ar), 6.77 (s, 1H, Ar), 6.95 (d, J = 8.9 Hz,
ꢀ
À1
+
Orange solid. Mp: 92–96 C. IR (KBr, cm ): 3,005,
1H, Ar), 7.65 (s, 1H, Ar). MS (ESI) m/z 289 [M ], 274
+
+
+
2
,956, 2,924, 2,852, 1,870, 1,736, 1,638, 1,524, 1,437,
([M ]–Me), 258 ([M ]–OMe), 243 ([M ]–Me, –OMe), 227
1
+
+
+
1
35, 1,170, 1,020. H NMR (300 MHz, DMSO-d ): 3.53
([M ]–2OMe), 199 ([M ]–CO Me, –OMe), 168 ([M ]–
6
2
(
s, 3H, CH ), 3.68 (s, 3H, CH ), 6.81 (d, J = 8.55 Hz,
CO Me, –2OMe), 137 (2-methyl-4-methoxyaniline),
3
3
2
1
8
H, Ar), 7.05–7.14 (m, 1H, Ar), 7.65–7.66 (m, 1H, Ar),
.15 (d, J = 7.92 Hz, 1H, Ar). MS (ESI) m/z 290 [M ],
122 (4-methoxyaniline), 77 (Ph).
+
+
+
+
2
2
2
1
75 ([M ]–Me), 244 ([M ]–Me, –OMe), 228 ([M ]–
+
+
OMe), 198 ([M ]–OMe, –Me, –NO ), 184 ([M ]–
4 | CONCLUSIONS
2
+
OMe, –NO ), 156 ([M ]–OMe, –CO Me, –NO ),
35 (nitroaniline), 128 ([M ]–2CO Me, –NO ), 91 (ani-
2
2
2
+
In this research, a novel nanostructure was prepared from
the titanomagnetite that was covered with silica, tryptophan
amino acid, and ethyl iodide consequently (Fe Ti O -
2
2
line), 59 (CO Me), 44 (NO ).
2
2
3
-x
x 4
+
3
À
SiO @TrpEt I ). The tryptophan and ethyl iodide were
2
3
.6 | General procedures for the
synthesis of 6-substituted 4-(2-methoxy-
-oxoethyl)quinoline-2-methylcarboxylates
5s–5x)
converted to the triethyltryptophanium iodide IL in situ.
The obtained nano inorganic–bio-organic core–shell was
characterized by FESEM, EDAX, FT-IR, TGA/DTG, VSM,
and XRF techniques. Its catalytic efficacy was examined to
yield a vast library of substituted quinolone-2-carboxylates
from different annulation MCRs such as three-component
reaction of aromatic amines, dialkyl acetylenedicarboxylates,
and terminal alkenes/ketones; pseudo three-component
reaction of anilines and dialkyl acetylenedicarboxylates; and
pseudo three-component reaction of anilines and methyl
2
(
A mixture of anilines (1, 0.4 mmol), methyl propiolate (6,
+
À
1.2 mmol), and nano Fe Ti O -SiO @TrpEt I (0.12 g)
3-x x 4 2 3
ꢀ
were stirred at 100 C until completion and investigated by
TLC (n-hexane/EtOAc eluent, 2:1). Next, methanol (10 ml)
was added and the catalyst was separated with an external
magnet. Purification of the products was done through PLC
to obtain the products 5s–5x (Scheme 1c and Table 6).
ꢀ
propiolate under solvent-free conditions at 100 C. The
notable points of this procedure are regioselective prepara-
tion of a wide-spread class of substituted quinolines, green
reaction media in the absence of any solvents, and hazard-
ous additives, and simple work-up procedure due to sepa-
ration from the nanocatalyst via an external magnet. The
protocol exhibited new mild outlook to obtain substituted
quinolines.
3
2
.6.1 | Methyl 6-bromo-4-(2-methoxy-
-oxoethyl)quinoline-2-carboxylate (5t)
ꢀ
À1
Yellow solid. Mp: 72–75 C. IR (KBr, cm ): 3,098,
3
,003, 2,924, 2,853, 1,732, 1,667, 1,609, 1,441, 1,201,
1
8
42. H NMR (300 MHz, DMSO-d ): 3.61–3.62 (s, 3H,
ACKNOWLEDGMENT
The authors thank to Alzahra University Research Coun-
cil for support of this work.
6
CH ), 3.66–3.97 (s, 2H, CH ), 3.77 (s, 3H, OCH ), 7.23–
7
1
3
2
3
.25 (m, 1H, Ar), 7.41–7.46 (m, 1H, Ar), 7.52–7.56 (m,
13
H, Ar), 8.61 (s, 1H, Ar). C NMR (75 MHz, DMSO-
d6): 38.66, 50.29, 51.24, 52.77, 130.94, 132.20, 133.42,
35.80, 138.94, 142.87–143.00, 149.11, 164.54, 167.71.
ORCID
1
Kobra Nikoofar https://orcid.org/0000-0002-3950-8229

14
NIKOOFAR AND MOLAEI YIELZOLEH
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