γ-Fe2O3@Si-(CH2)3@mel@(CH2)4SO3H as a magnetically bifunctional and retrievable nanocatalyst for green synthesis of benzo[c]acridine-8(9H)-ones and 2-amino-4H-chromenes

Article abstract of DOI:10.1080/24701556.2020.1802751

The present work describes the synthesis and characterization of melamine functionalized with sulfonic acid supported on the magnetic nanoparticle, γ-Fe₂O₃@Si-(CH₂)₃@melamine@butyl sulfonic acid nanoparticle as

Full text of DOI:10.1080/24701556.2020.1802751

Inorganic and Nano-Metal Chemistry
ISSN: (Print) (Online) Journal homepage: https://www.tandfonline.com/loi/lsrt21
γ-Fe2O3@Si-(CH2)3@mel@(CH2)4SO3H as a
magnetically bifunctional and retrievable
nanocatalyst for green synthesis of
benzo[c]acridine-8(9H)-ones and 2-amino-4H-
chromenes
Fatemeh Karimirad & Farahnaz Kargar Behbahani
To cite this article: Fatemeh Karimirad & Farahnaz Kargar Behbahani (2020): γ-Fe2O3@Si-
(CH2)3@mel@(CH2)4SO3H as a magnetically bifunctional and retrievable nanocatalyst for green
synthesis of benzo[c]acridine-8(9H)-ones and 2-amino-4H-chromenes, Inorganic and Nano-Metal
Chemistry, DOI: 10.1080/24701556.2020.1802751
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INORGANIC AND NANO-METAL CHEMISTRY
https://doi.org/10.1080/24701556.2020.1802751
c-Fe2O3@Si-(CH2)3@mel@(CH2)4SO3H as a magnetically bifunctional and
retrievable nanocatalyst for green synthesis of benzo[c]acridine-8(9H)-ones
and 2-amino-4H-chromenes
Fatemeh Karimirad and Farahnaz Kargar Behbahani
Department of Chemistry, Karaj Branch, Islamic Azad University, Karaj, Iran
ABSTRACT
ARTICLE HISTORY
Received 31 March 2020
Accepted 12 July 2020
The present work describes the synthesis and characterization of melamine functionalized with
sulfonic acid supported on the magnetic nanoparticle, c-Fe2O3@Si-(CH2)3@melamine@butyl sul-
fonic acid nanoparticle as a green and retrievable bifunctional catalyst. This catalyst was assigned
by FT-IR, XRD, EDX, TEM, VSM, CHN, and TGA analyses. In addition, the catalytic activity of this
new catalyst was investigated for the synthesis of 7,10,11,12-tetrahydrobenzo[c]acridine-8(9H)-ones
from aliphatic and aromatic aldehydes, dimedone and 1-naphthylamine in excellent yields and 2-
amino-4H-chromenes were provided using manufactured nanocatalyst in good-to-high yield under
mild reaction condition. The c-Fe2O3@Si-(CH2)3@melamine@butyl sulfonic acid heterogeneous
catalyst showed the advantages such as very simple and eco-friendly due to use from magnetic
nanoparticles as high reusability of the catalyst, magnetically separable catalyst, excellent yield,
and mild reaction condition. The synthesis of some new derivatives of dibenzo[c]acridines and 2-
amino-4H-chromenes in the presence of this nanocatalyst is also reported.
KEYWORDS
c-Fe2O3@Si-
(CH2)3@melamine@butyl
sulfonic acid; nanoparticle;
melamine;
acridine; chromene
Introduction
needing to catalyst filtration or centrifugation, and providing
simple and practical method for the recovering of these
catalysts. Also, multi-component reactions (MCRs) are very
powerful weapons in the organic and medicinal chemistry for
the preparation of the bulky products in a one-pot and
almost one-step from small starting materials. The combin-
ation of magnetic nanocatalysts and MCRs will become a
merits protocol for the introducing of green procedures in
green synthesis.[30] Moreover, on the base of the best our
knowledge, c-Fe2O3@Si-(CH2)3@melamine@butyl sulfonic
acid as a new, reusable, bifunctional heterogeneous nanopar-
ticles catalyst was first utilized in the one-pot preparation of
benzo[c]acridines. In this communication, in the present
work, we enclosed the synthetic applicability of a prepared
catalyst (magnetic-based butyl sulfonic acid–melamine com-
plex) in the synthesis of benzo[c]acridines in one-pot and
under mild reaction condition in ethanol at 60ꢀC with low
reaction times (Scheme 1).
Almost the heterocyclic compounds are the most attention in
pharmaceutical chemistry. Among heterocyclic compounds, the
tricyclic compounds containing acridine skeleton is a significant
pharmacophore and interesting structure in pharmacology.
Acridine derivatives have antitumor,[1] carcinogenic,[2] and
anti-malaria activities.[3] In addition, these organic compounds
can be applied for heart defibrillation[4] and as DNA-intercalat-
ing anticancer drugs.[5] Therefore, the synthesis of acridine
derivatives is principal task in modern organic chemistry.
Although numerous methods have been introduced in the pro-
viding of benzoacridine derivatives,[6–15] in recent studies,
Borah’s group successfully synthesized benzoacridine derivatives
via N,N-disulfo-1,1,3,3-tetramethylguanidinium carboxylate
ionic liquids as a catalyst,[16] Murugesan et al. used sulfonic
acid functionalized boron nitride as a catalyst in the prepar-
ation of acridine derivatives,
[17]
Wan et al. modified glucose
sulfonic acid and applied in the synthesis of acridine deriva-
tives,[18] and Shen et al. synthesized acridine derivatives using
imidazolium salts as ionic liquids catalyst,[19] but these methods
in spite of advantages have their shortcomings, such as low
yield, high reaction temperature, and prolong reaction time.
On the other hand, more progress in the field of green
synthesis has reported magnetically recoverable nanocatalysts
which possess expansive surface area, high activity, reusability,
and long lifetime.[22–29] The use of magnetic nanocatalysts is
an interesting area for the development of sustainable and
Experimental
Chemicals were purchased from Merck Chemical Company.
Drying of the solvents was done using standard methods.
NMR spectra were recorded in CDCl3 and DMSO-d6 on a
Bruker Advance DPX-300 instrument, Germany country.
SEM analysis was determined by using FE-TESCAN, model
Mira3-XMU, Czech Republic country at accelerating voltage
green procedures due to external magnetic separation and no of 15 KV. TEM analysis was performed using Philips CM30
CONTACT Farahnaz Kargar Behbahani
ß 2020 Taylor & Francis Group, LLC
Farahnazkargar@yahoo.com
Department of Chemistry, Karaj Branch, Islamic Azad University, Karaj, Iran.

2
F. KARIMIRAD AND F. K. BEHBAHANI
instrument, Nederland country. XRD analysis was measured on
a Bruker D8-advance X-ray diffractometer or on an X’Pert Pro
MPD diffractometer, Nederland country with Cu Ka
(k ¼ 0.154 nm) radiation. TGA analysis was recorded using a
Shimadzu Thermogravimetric analyzer (TG-50), Japan country.
FT-IR spectra were recorded on a JASCO FT-IR 460 plus spec-
trophotometer, Japan country. Elemental analysis was performed
on a Costech 4010 CHN elemental analyzer, Italy country.
Synthesis of c-Fe2O3@Si-(CH2)3@melamine@butyl sulfonic acid
nanoparticle. The synthesis of magnetic Fe3O4 nanoparticles,
c-Fe2O3@Si-(CH2)3Cl nanoparticles, and c-Fe2O3@Si-
(CH2)3@melamine nanoparticles were carried out according
to the previous procedure reported in the literature.[31,32]
Then, the c-Fe2O3@Si-(CH2)3@melamine nanoparticles
(1.0 g) were sonicated in 30 mL of dry THF at 30 min. Next,
1,4-butane sultone (5.0 mmol) was added and refluxed at
24 h. Then, the catalyst was separated using an external
magnet, washed with ethanol (3 ꢁ 15 mL), water
(2 ꢁ 15 mL), and dried in a vacuum oven at 50 ꢀC and 4.0 h
(Scheme 2).
General procedure for the synthesis of 7,10,11,12-tetrahy-
drobenzo[c]acridine-8(9H)-ones using c-Fe2O3@Si-
(CH2)3@melamine@butyl sulfonic acid. A mixture of 1-naph-
thylamine (1.0 mmol), dimedone (1.0 mmol), aldehydes
(1.0 mmol), and prepared magnetic nanoparticle (0.004 g) in
ethanol (2.0 mL) was taken in a flask and the reaction mix-
ture was mixed at 60 ꢀC for appreciating times in Table 1.
The progress of the reaction was monitored by TLC. After
completion of the reaction, the catalyst was removed with
an external magnet and then water poured to the reaction
mixture to obtain precipitation. Finally, the isolated precipi-
tation recrystallized with ethanol to attained absolute prod-
uct in 95% yield.
Reusability of the catalyst
The reusability of the catalyst was examined in the synthesis
of 4a. At the end of the reaction, the catalyst was removed
with an external magnet and washed with ethanol (2ꢁ 5 mL)
and then used it without further purification. The separated
catalyst was reused three times in the preparation of 4a with-
out considerable loss of its catalytic activity (entry 1, Table 1;
95%, 95%, and 94%). In addition, FT-IR analysis was exhib-
ited that the catalytic activity of the catalyst was the same as
those of the freshly used catalyst (Figure 1).
Results and discussion
Characterization of the nanocatalyst
The FT-IR spectra of the intermediate nanoparticles and
final catalyst are shown in Figure 2. The band at 1025 cmꢂ1
Scheme 1. Providing of benzo[c]acridin-8(7H)-ones.
Scheme 2. Manufactured of c-Fe2O3@Si-(CH2)3@melamine@butyl sulfonic acid nanoparticle.

INORGANIC AND NANO-METAL CHEMISTRY
3
Figure 1. FT-IR spectra of the recovered c-Fe2O3@Si-(CH2)3@Mel@butylSO3H after three runs.
Figure 2. FT-IR spectra of intermediate nanoparticles and prepared catalyst: c-Fe2O3 (a), c-Fe2O3@Si-(CH2)3Cl (b), c-Fe2O3@Si-(CH2)3@Mel (c), and c-Fe2O3@Si-
(CH2)3@Mel@butylSO3H (d).
relatives to SiO of c-Fe2O3@Si-(CH2)3 the nanoparticles, and
Also, the XRD pattern of the catalyst is shown in Figure 4.
that at 2921 cmꢂ1 is related to CH2 of propyl in The reflection planes of (220), (311), (400), (422), (511), and
c-Fe2O3@Si-(CH2)3 nanoparticles. The band at 3424 and (440) at 2h ¼ 30.3, 35.7, 43.4, 53.8, 57.4, and 63.0, which are
3415 cmꢂ1 confirms the presence of NH2 group of mela- attributed to the diffraction scattering of c-Fe2O3 were readily
mine, loaded on the surface of c-Fe2O3@Si-(CH2)3@Mel. recognized from the XRD pattern. These characteristic peaks
The broadband at 3380 cmꢂ1 corresponds to the OH group, adopted with those of standard c-Fe2O3 (JCPDS file No 04-
and that at 1653 cmꢂ1 is related to S ¼ O of SO3H in 0755). The observed diffraction peaks were indicated that
c-Fe2O3@Si-(CH2)3@Mel@butylSO3H.
c-Fe2O3 mostly exist in a face-centered cubic structure.
The TGA curve of the synthesized catalyst is indicated in
The SEM and TEM images of the synthesized magnetic
Figure 3. The first mass loss up to 160 ꢀC (region A) is due nanocatalyst are shown in Figures 5–7. As can be seen from
to the release of adsorbed water; the second from 200 to SEM images (Figure 5), the geometric shape of the nanopar-
515 ꢀC is related to the decomposition of organic matter on ticles is spherical. To investigate the morphology and topog-
the c-Fe2O3 core (region B). Region C attributes to c-Fe2O3. raphy of the described catalyst, TEM was carried out as
The TGA curve of the synthesized catalyst demonstrates shown in Figure 6. As it is clearly approved the spherical
high thermal stability, with decomposition starting at around uniform of the catalyst particles and confirmed that the
200 ꢀC under a nitrogen atmosphere.
catalyst has nanosize particles.

4
F. KARIMIRAD AND F. K. BEHBAHANI
The cumulative distribution function shows that the nano-
particles have sizes between 12 and 24 nm that the utmost of
nanoparticle size was 17 nm (Figure 7), respectively, that
according to research, the smaller and uniform particles
exhibited better physical and magnetic properties.[28]
The loading amount of melamine on c-Fe2O3@Si-
(CH2)3@melamine was determined by elemental analysis,
and the C, N, and
H
contents of c-Fe2O3@Si-
(CH2)3@melamine was quantified 9.56, 9.88, and 1.55,
respectively, that it can result from 1.2 mmol melamine on
the surface of c-Fe2O3@Si-(CH2)3. Thus c-Fe2O3@Si-
(CH2)3@melamine can react with 4.8 mmol 1,4-butan sul-
tone to achieve SO3H functionalized theoretically, whereas
the S content of c-Fe2O3@Si-(CH2)3@melamine@SO3H was
4.1 mmol approximately based on EDAX analysis (Figure 8).
To evaluate the magnetic properties of c-Fe2O3@Si-
(CH2)3@Mel@butylSO3H and to investigate the effect of Si-
(CH2)3@Mel@butylSO3H on the magnetic feature of
Figure 3. TGA analysis of c-Fe2O3@Si-(CH2)3@Mel@butylSO3H. A) c-Fe2O3@Si-
(CH2)3@Mel@butylSO3H without H2O; B) c-Fe2O3@Si-(CH2)3@Mel, c-Fe2O3@Si-
(CH2)3; C) c-Fe2O3.
Figure 4. XRD analysis of c-Fe2O3@Si-(CH2)3@Mel@butylSO3H.
Figure 5. SEM analysis of c-Fe2O3@Si-(CH2)3@Mel@butylSO3H.

INORGANIC AND NANO-METAL CHEMISTRY
5
Figure 6. TEM analysis of c-Fe2O3@Si-(CH2)3@Mel@butylSO3H.
Figure 7. Particle size of c-Fe2O3@Si-(CH2)3@Mel@butylSO3H.
Figure 8. EDX analysis of c-Fe2O3@Si-(CH2)3@Mel@butylSO3H.
c-Fe2O3, the magnetic property of c-Fe2O3@Si- (CH2)3@Mel@butylSO3H and c-Fe2O3, the magnetic prop-
(CH2)3@Mel@butylSO3H was performed via VSM analysis erty decreased from 95 to 65 emugꢂ1. This result is not
and compared with that of c-Fe2O3. The results, in Figure 9 beyond expectation as incorporation of nonmagnetic com-
showed
that
upon
bounding
between
Si- ponent, Si-(CH2)3@Mel@butylSO3H, can decrease the

6
F. KARIMIRAD AND F. K. BEHBAHANI
Table 1. Synthesis of 7,10,11,12-tetrahydrobenzo[c]acridine-8(9H)-ones using
c-Fe2O3@Si-(CH2)3@melamine@butyl sulfonic acid nanoparticle.
Entry
1
Aldehyde
Product Time (min) Yield%a m.p (ꢀC) [ref.]
4a
4b
4c
15
15
10
95
90
98
258–261[10]
260–260[13]
284–286[7]
O
H
2
3
O
Cl
Cl
H
O
H
Cl
4
5
4d
4e
10
25
95
95
268–270[14]
175–178 [14]
O
H
Figure 9. VSM analyses of c-Fe2O3@Si-(CH2)3@Mel@butylSO3H and c-Fe2O3.
O2N
magnetic property. Despite the decrease of the magnetic
property, c-Fe2O3@Si-(CH2)3@Mel@butylSO3H could be
magnetically recovered via using an external magnet.
O
H
Catalytic activity evaluation
6
7
4f
30
50
92
93
277–279 [33]
219–221[14]
O
Me2N
To examine the solvent type effect on the reaction yield and
time, the model reaction for the providing of 4a was sub-
jected in various solvents including dimethylformamide
(DMF), water, tetrahydrofuran (THF), dimethylsulfoxide
(DMSO) and ethanol, n-hexane, dichloromethane, ethyl
acetate, and without solvent. The results are presented in
Table 2. The reaction was first carried out at room tempera-
ture and 60 ꢀC under solvent-free condition in 120 min and
the product was resulted in 10% and 35% yield. When the
benchmark reaction was tested by the above mention sol-
vents, the desired product was yielded in better condition
than without solvent. As can be seen in Table 2, the best
solvent was ethanol. To more investigate the catalyst amount
effect on the reaction time, the obtained optimum solvent
was repeated in the different amount of the catalyst includ-
ing to 0.002, 0.004, 0.006 g, and without the catalyst. As one
can see, in the absence of catalyst, even with a time greater
than 15 min, the yield is low (45%). Also, increasing the
catalyst amount to 0.006 g did not effect on reaction time
and yield. So, the catalyst is essential component for the
progress of the reaction. Therefore, entry 9, Table 2 was
used as the best optimum reaction condition.
Also, the model reaction was examined for the synthesis
of 4a in the presence of c-Fe2O3, c-Fe2O3@Si-(CH2)3Cl,
c-Fe2O3@Si-(CH2)3@Mel and the results were compared
with those of using c-Fe2O3@Si-(CH2)3@Mel@butylSO3H.
As shown in Table 1, the best result was obtained by
c-Fe2O3@Si-(CH2)3@Mel@butylSO3H (entry 5, Table 3).
To generalize this model reaction, the optimum reaction
condition was fixed for a series of aliphatic and aromatic
aldehydes with electron-withdrawing and electron-donating
H
4g
O
H
OH
8
4h
60
91
267–270[6]
O
H
OMe
9
4i
4j
30
40
90
94
190–192 [34]
187–191[14]
O
10
O
H
HO
11
4k
35
90 214–216 (new)
O
H
Me2C
aIsolated yield.
excellent. Therefore, this protocol is suitable for both ali-
phatic and aromatic aldehydes bearing electron-releasing
and electron-withdrawing groups. Also, cinnamaldehyde and
acetaldehyde were subjected as aliphatic aldehydes under
reaction condition and the reaction was carried out well in
good yields and short reaction times (entry 5 and 9, Table
groups for the synthesis of the corresponding dibenzo[c] 1). In addition, the method is easy to operate, very simple,
acridines. Found in Table 1, in all cases, the yields were and eco-friendly due to use from magnetic nanoparticle as

INORGANIC AND NANO-METAL CHEMISTRY
7
Table 2. The optimization of reaction condition for the preparation of 4a
using c-Fe2O3@Si-(CH2)3@melamine@butyl sulfonic acid nanoparticle.
Entry
Catalyst (g)
Solvent
Temp. (oC)
Time (min)
Yielda%
1
1
2
3
4
5
6
7
8
9
10
11
12
13
0.004
0.004
0.004
0.004
0.004
0.004
0.004
–
0.002
0.004
0.006
0.004
0.004
0.004
Free
Free
H2O
EtOH
THF
r.t
60
100
r.t.
60
60
60
60
60
60
60
Reflux
Reflux
Reflux
120
120
15
300
120
60
60
120
20
15
15
180
180
180
10
35
60
75
40
55
60
45
90
95
95
10
10
75
DMF
DMSO
EtOH
EtOH
EtOH
EtOH
n-Hexane
CH2Cl2
EtOAc
Scheme 3. Synthesis of 2-amino-4H-chromenes.
Table 4. Preparation of 2-amino-4H-chromene.
Entry
1
Aldehyde
Product Time (min) Yield%a m.p (ꢀC) [ref.]
6a
15
92
227–228 [37]
aReaction condition: 1-naphthylamine (1 mmol), dimedone (1 mmol), benzalde-
hyde (1 mmol) catalyst in solvent (5 mL) at different times.
O
O
2
6b
10
90
201–203[37]
NO2
Table 3. The optimization of reaction condition for the preparation of 4a
using different of nanoparticle catalysts.
Entry
Catalyst
Yielda%
1
2
3
4
5
Free
c-Fe2O3
c-Fe2O3@Si-(CH2)3Cl
c-Fe2O3@Si-(CH2)3@Mel
35
40
40
55
95
3
4
6c
25
40
95
80
210–212[37]
202–204[39]
c-Fe2O3@Si-(CH2)3@Mel@butylSO3H
aReaction condition: 1-naphthylamine (1 mmol), dimedone (1 mmol), benzalde-
6d
H3CO
hyde (1 mmol), catalyst (0.004 g) in ethanol (5 mL) at 60 ꢀC and in 15 min.
O
O
H
high reusability of the catalyst, magnetically separable cata-
lyst, excellent yield, and mild reaction condition. All com-
pounds have been characterized based on physical and
spectral data and were good matched with authentic samples
in the literature (Table 1). Also, when we used 4-isopropyl
benzaldehyde, we obtained a new derivative of benzo[c]acri-
dines in good yield (entry 11, Table 1).
5
6
6e
6f
25
45
85
82
208–210 (new)
245–247 (new)
Me2C
H
N
O
O
Owing to wide range of useful biological activities in the
field of medicinal chemistry[35] and to have anti-cancer and
anti-coagulant activities[36] of 2-amino-4H-chromenes and,
to evaluate catalytic activity of prepared catalyst, the synthe-
sis of 2-amino-4H-chromenes was studied using aryl alde-
hydes, dimedone, and malononitrile in the presence of
prepared nanocatalyst in good-to-high yield (Scheme 3).
The results have been shown in Table 4. The main
advantages of this synthesis method are mild reaction condi-
tion, separation of the catalyst using external magnet, eco-
friendly, non-corrosive, and reusable catalytic system at least
five times without loss of activity with high isolated yield of
the products and the synthesis of two new derivatives of 2-
amino-4H-chromene (entry 5 and 6, Table 4).
aReaction condition: malononitril (1.0 mmol), dimedone (1.0 mmol), benzalde-
hyde (1.0 mmol) and catalyst (0.004 g) in ethanol (2.0 mL) at 60 ꢀC.
synthesis of 10,10-dimethyl-7-phenyl-7,10,11,12-tetrahydro-
benzo [c]acridine-8(9H)-one (4a) and 2-Amino-7,7-
dimethyl-5-oxo-4-phenyl-5,6,7,8-tetrahydro-4H-chromene-3-
carbonitrile (6a) under various conditions (Tables 5 and 6).
The advantages of our procedure are the use of c-Fe2O3@Si-
(CH2)3@melamine@butyl sulfonic acid as heterogeneous,
high reusability of the bifunctional, and magnetically separ-
able catalyst, excellent yield and mild reaction condition,
which are very important in the chemical industry.
The suggested mechanism for the preparation of
7,10,11,12-tetrahydrobenzo[c]acridine-8(9H)-ones has been
depicted in Scheme 4. As shown in Scheme 4, the enolic
form of dimedone 1 attacks to activated-magnetic nanocata-
lyst aldehyde 2 to form intermediate 3. Dehydration of 3
obtains Knoevenagel product 4. Michel like-addition of 1-
naphtyl amine 5 to 4 and following cyclization and assisted-
dehydration via basic part of the catalyst give intermediate 8
that is tatumerized to 4.
Conclusion
In summary, the synthesis of dibenzo[c]acridines has been
developed using a magnetic nanocatalyst catalyst. The reac-
tion is usable to a wide variety of aliphatic and aromatic
aldehydes with excellent yields. This synthesis protocol
develops an attractive pathway for dibenzo[c]acridines pro-
duction using a magnetic nano bifunctional catalyst, and
forming H2O as the sole byproduct. Also, 2-amino-4H-chro-
menes was synthesized in the presence of prepared nanoca-
To show the merits of this procedure in comparison with
the previously reported protocols, we compared the talyst in good-to-high yield under mild reaction condition.

8
F. KARIMIRAD AND F. K. BEHBAHANI
Scheme 4. Proposed mechanism for the synthesis of tetrahydrobenzo[c]acridine-8(9H)-ones.
Table 5. Synthesis procedure for the synthesis of 4a using different catalysts.
Entry
Catalyst
Temp. (ꢀC)
Time (min)
Yield%
Ref.
a
1
2
3
4
5
6
7
8
9
FePO4 (10 mol.%)
20
r.t.
60
60
20
30
60
60
120
1200
15
90
95
93.5
96
85
85
70
28
95
14
34
10
33
12
13
15
6
L-Prolinea (10 mol.%)
MW/ 160 wb
Succinimide-N-sulfonic acida (4 mol%)
ultrasonic wavesa
60
r.t.
r.t.
110
80
SnCl2 .2H2O (20 mol%) / ultrasonic irradiationa
NH2SO3H/ H6P2W18O62 .18H2O
Without catalyst
Presented catalysta, (0.004 g)
60
This work
aUsed solvent is EtOH.
bSolvent-free.
cc-Fe2O3@Si-(CH2)3@melamine@butyl sulfonic acid.
Table 6. Synthesis protocol for the preparation of 6a using different catalysts.
Entry
Catalyst
ZnO nanoparticle(0.003 g)
MNPs@Cu (0.01 g)
L-proline (10 mol.%)
Ba(OTf)2(20 mol.%)
Solvent
EtOH
Free
EtOH
PEG-water
H2O
Temp. (ꢀC)
Time (min)
Yield%
Ref.
1
2
3
4
5
6
Reflux
90
Reflux
r.t.
100
60
10
17
60
30
180
15
90
91
93
88
94
92
38
39
37
40
41
MCM-41@Schif base (0.01 g)/Co(OAc)2 (10 mol%)
Presented catalysta (0.004 g)
EtOH
This work
ac-Fe2O3@Si-(CH2)3@melamine@butyl sulfonic acid.

INORGANIC AND NANO-METAL CHEMISTRY
9
Another advantage of this method is the synthesis of some
new derivatives of dibenzo[c]acridines and 2-amino-
4H-chromenes.
Physical and spectra data for new compounds
10,10-Dimethyl-7-(4-isopropylphenyl)-9,10,11,12-tetrahydro-
benzo[c]acridin-8(7H)-one (4k). Melting point: 214–216 ꢀC:
withe powder, IR (KBr, cmꢂ1): 3321, 3060, 2897, 1667, 1567,
1522, 1435, 1340, 1275, 815; 1H NMR (300 MHz, CDCl3)
d:1.00 (s, 3H), 1.19 (s, 3H), 1.21 (6H, d, J ¼ 7.67 Hz,
2 ꢁ CH3), 2.22–2.44 (m, 2H), 2.55–2.80 (m, 2H), 3.11 (1H,
m, CH), 5.26 (s, 1H), 7.15–7.77 (m, 9H), 8.77 (d, J¼ 7.6 Hz,
1H), 9.33 (s, 1H, NH). 13C NMR (DMSO–d6): d (ppm) ¼
198, 146,140, 137, 134, 132, 128, 126, 124,118, 108, 51, 42,
36, 31, 30, 27, 23. Combustion analysis for C28H29NO:
Calculated (%). C, 85.02; H, 7.39; N, 3.54; found (%): C,
85.01; H, 7.36; N, 3.52.
FT-IR spectra data
10,10-Dimethyl-7-phenyl-7,10,11,12-tetrahydrobenzo[c]-acri-
din-8(9H)-one (4a). IR (KBr, cmꢂ1): 3301 (NH), 3083 (CH-
aromatic), 2956 (CH-aliphatic), 1689 (C ¼ O), 1595 (C ¼ C
aromatic), 1072.
3,3-Dimethyl-9-(4-chlorophenyl)-1,2,3,4,9,10-hexahydro-
benzo-[c]acridine-1-one (4b).
IR (KBr, cmꢂ1): 3334 (NH), 3030 (CH-aromatic), 2958
(CH-aliphatic), 1605 (C ¼ O), 1572 (C ¼ C aromatic), 1492,
1374, 1262, 1148, 1090, 1014, 851, 822, 757.
2-amino-7,7-dimethyl-5-oxo-4-(4-isopropylphenyl)-5,6,7,8-
tetrahydro-4H-chromene-3-carbonitrile (6e): Melting point:
208–2110 ꢀC,: withe powder, IR (KBr/cmꢂ1): 3395, 3324
(NH2), 2199 (CN), 1680 (C ¼ O), 1214 (C-O). 1H NMR
(DMSO–d6): d (ppm) ¼ 0.98 (3H, s, Me), 1.06 (3H, s, Me),
1.23 (6H, d, J ¼ 7.67 Hz, 2 ꢁ CH3), 2.10 (1H, d, J ¼ 16.0 Hz,
H-6), 2.25 (1H, d, J ¼ 16.0 Hz, H-6) , 2.49 (2H, brs, CH2),
3.12 (1H, m, CH), 4.19 (1H, s, H-4), 7.02 (2H, brs, NH2),
3,3-Dimethyl-9-(2,4-dichlorophenyl)-1,2,3,4,9,10-hexahy-
drobenzo[c]acridine-1-one (4c). IR (KBr, cmꢂ1): 3304 (NH),
3065 (CH-aromatic), 2960 (CH-aliphatic), 1684 (C ¼ O),
1590, 1518 (C ¼ C aromatic), 1385, 1262, 1149, 1095, 1037,
880, 807, 754.
3,3-Dimethyl-9-(3-nitrophenyl)-1,2,3,4,9,10-hexahydro-
benzo- [c]acridine-1-one (4d).
IR (KBr, cmꢂ1): 3310 (NH), 3050 (CH-aromatic), 2956 7.10
(2H,
d,
J ¼ 8.24 Hz,H–Ar),
7.13
(2H,
d,
J ¼ 8.24 Hz,H–Ar). 13C NMR (DMSO–d6): d (ppm) ¼ 198,
159, 155, 142,139, 128, 125, 117, 113, 58, 56, 44, 37, 36, 30,
27, 23. Combustion analysis for C21H24N2O2: Calculated
(%). C, 74.97; H, 7.19; N, 8.33; found (%): C, 74.95; H, 7.17;
N, 8.30.
(CH-aliphatic), 1589 (C ¼ O), 1530 (C ¼ C aromatic), 1387,
1262, 1150, 1093, 831, 807, 758, 611.
10,10-Dimethyl-7-(2-phenylethenyl)-7,10,11,12-tetrahydro-
benzo[c]acridin-8(9H)-one (4e). IR (KBr, cmꢂ1): 3342 (NH),
3080 (CH-aromatic), 2956 (CH-aliphatic), 1635 (C ¼ O),
1590, 1557 (C ¼ C aromatic).
N-(4-(2-amino-3-cyano-7,7-dimethyl-5-oxo-5,6,7,8-tetrahy-
dro-4H-chromen-4-yl)phenyl)acetamide (6f): Melting point:
245–247 ꢀC, withe powder, IR (KBr/cm-1): 3395, 3328
(NH2), 2199 (CN), 1680 (C ¼ O), 1667 (C ¼ O), 1214 (C-O).
1H NMR (DMSO–d6): d (ppm) ¼ 0.97 (3H, s, Me), 1.05
(3H, s, Me), 2.00 (3H, s, Me), 2.08 (1H, d, J ¼ 16.0 Hz, H-6),
2.24 (1H, d, J ¼ 16.0 Hz, H-6 0), 2.49 (2H, brs, CH2), 4.10
(1H, s, H-4), 6.98 (2H, brs, NH2), 7.04 (2H, d, J ¼ 8.0 Hz,
H–Ar), 7.24 (2H, d, J ¼ 8.0 Hz, H–Ar), 9.90 (1H, s, NH).
13C NMR (DMSO–d6): d (ppm) ¼ 198, 168,159, 155,
137,135, 128, 121, 117, 113, 58, 51, 44, 37, 30, 27, 22.
Combustion analysis for C20H21N3O3: Calculated (%). C,
68.36; H, 6.02; N, 11.96; found (%): C, 68.32; H, 6.01;
N, 11.93.
10,10-Dimethyl-7-(4-dimethylaminophenyl)-9,10,11,12-tet-
rahydrobenzo[c]acridin-8(7H)-one (4f). IR (KBr, cmꢂ1): 3321
(NH), 3066 (CH-aromatic), 2898 (CH-aliphatic), 1666
(C ¼ O), 1577, 1522 (C ¼ C aromatic), 1435, 1140, 815.
10,10-Dimethyl-7-(2-hydroxyphenyl)-7,10,11,12-tetrahydro-
benzo[c]acridin-8(9H)-one (4 g). IR (KBr, cmꢂ1): 3500 (NH),
3100 (CH-aromatic), 2997 (CH-aliphatic), 1641 (C ¼ O),
1587, 1515 (C ¼ C aromatic), 1487, 1409, 1260, 1175, 1143,
1026, 845, 819, 755, 746.
7,10,10-Trimethyl-9,10,11,12- tetrahydrobenzo[c]acridin-
8(7H)-one (4 h). IR (KBr, cmꢂ1): 3336 (NH), 3087 (CH-aro-
matic), 2987 (CH-aliphatic), 1643 (C ¼ O), 1543, 1532
(C ¼ C aromatic), 1465, 1132, 818.
7-(3-Hydroxyphenyl)-10,10-dimethyl-7,10,11,12-tetrahydro-
benzo[c]acridin-8(9H)-one (4i). IR (KBr, cmꢂ1): 3314 (NH),
3070 (CH-aromatic), 2956 (CH-aliphatic), 1640 (C ¼ O),
1550, 1520 (C ¼ C aromatic), 1468, 1047.
Disclosure statement
No potential conflict of interest was reported by the authors.
2-amino-7,7-dimethyl-5-oxo-4-phenyl-5,6,7,8-tetrahydro-
4H-chromene-3-carbonitrile (6a). IR (KBr/cmꢂ1): 3395, 3324
(NH2), 2199 (CN), 1680 (C ¼ O), 1214 (C-O).
References
2-Amino-7,7-dimethyl-4-(3-nitrophenyl)-5-oxo-5,6,7,8-tet-
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3429, 3334 (NH2), 2186 (CN), 1680 (C ¼ O), 1210 (C-O).
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