Fe3O4@NCs/BF0.2: A magnetic bio-based nanocatalyst for the synthesis of 2,3-dihydro-1H-perimidines

Article abstract of DOI:10.1002/jccs.201900004

Nanocellulose (NC) materials have some unique properties, which make them attractive as organic or inorganic supports for catalytic applications. Nanocatalysts with diameters of less than 100 nm are difficult to separate from the reaction mixture, therefo

Full text of DOI:10.1002/jccs.201900004

Received: 2 January 2019
Revised: 28 March 2019
Accepted: 1 April 2019
DOI: 10.1002/jccs.201900004
A R T I C L E
Fe3O4@NCs/BF0.2: A magnetic bio-based nanocatalyst
for the synthesis of 2,3-dihydro-1H-perimidines
Bi Bi Fatemeh Mirjalili
| Mahnaz Imani
Department of Chemistry, College of
Science, Yazd University, Yazd, I. R. Iran
Nanocellulose (NC) materials have some unique properties, which make them attrac-
tive as organic or inorganic supports for catalytic applications. Nanocatalysts with
diameters of less than 100 nm are difficult to separate from the reaction mixture, there-
fore, magnetic nanoparticles (MNPs) were used as catalysts to overcome this problem.
Fe3O4@NCs/BF0.2 as a green, bio-based, eco-friendly, and recyclable catalyst was syn-
thesized and characterized using fourier-transform infrared spectroscopy (FT-IR),
vibrating sample magnetometer (VSM), X-ray diffraction (XRD), X-ray fluorescence
(XRF), Brunauer–Emmett–Teller (BET), field emission scanning electron microscopy
(FESEM), transmission electron microscopy (TEM), and thermal gravimetric analysis
(TGA) techniques. Fe3O4@NCs/BF0.2 was employed for the synthesis of 2,3-dihydro-
1H-perimidine derivatives via a reaction of 1,8-diaminonaphthalene with various alde-
hydes at room temperature under solvent-free conditions. The present procedure offers
several advantages including a short reaction time, excellent yields, easy separation of
catalyst, and environmental friendliness.
Correspondence
Bi Bi Fatemeh Mirjalili, Department of
Chemistry, College of Science, Yazd
University, Yazd, 89195-741, I. R. Iran.
Email: fmirjalili@yazd.ac.ir
Funding information
Research Council of Yazd University
K E Y W O R D S
1,8-diaminonaphthalene, bio-based catalyst, Fe3O4@NCs/BF0.2, nanocellulose, perimidine
Cellulose has important properties such as biocompatibil-
ity, biodegradability, low toxicity,[11] and functionalized sur-
1 | INTRODUCTION
face.[12,13] Nanocellulose (NC) materials have some unique
properties, which make them attractive for organic or inor-
ganic supports for catalytic applications. Nanocatalysts with
diameters of less than 100 nm are difficult to separate from
the reaction mixture, therefore, magnetic nanoparticles
(MNPs) were used as catalysts to overcome this problem.
Also MNPs in chemical synthesis offer advantages such as
nontoxic, retrievable, readily accessible,[14] low price, good
stability, and easy separation by magnetic forces.[15–18]
In this work, Fe3O4@nanocellulose/BF0.2 (Fe3O4@
NCs/BF0.2) was synthesized as a new NC-based super-
paramagnetic nanocatalyst. This catalyst was successfully
applied to the synthesis of 2,3-dihydro-1H-perimidine deriv-
atives by cyclocondensation of 1,8-diaminonaphthalene with
aromatic aldehydes.
Perimidines constitute an important class of natural and
non-natural products. They have attracted great attention
in synthetic organic chemistry for several reasons, includ-
ing biological activities, pharmacological applications
such as anti-inflammatory, antibacterial, antimicrobial,
antifungal, antitumor, antihypertensive, and antivirucidal
agents.[1–3]
A synthetic method for the preparation of perimidines is
the condensation reaction of 1,8-diaminonaphthalene with
various carbonyl compounds such as carboxylic acids, anhy-
drides, acid halides, ketones, or aldehyde reagents.[4] These
compounds have been synthesized in the presence of various
catalysts, such as, FePO4,[5] Cu(NO3)2Á6H2O,[6] nanosilica
sulfuric acid,[7] NaY zeolite,[8] nano-CuY zeolite,[9]
N-bromosuccinamide,[2] and CMK-5-SO3H.[10]
© 2019 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
J Chin Chem Soc. 2019;1–8.
http://www.jccs.wiley-vch.de
1

2
MIRJALILI AND IMANI
(a)
(b)
FIGURE 2 (a) TEM and (b) FESEM images of Fe3O4@
SCHEME 1 Graphical representation of Fe3O4@ NCs/BF0.2
NCs/BF0.2
preparation
NC, Fe3O4@NCs, and Fe3O4@ NCs/BF0.2 are shown in
Figure 1.
2 | RESULTS AND DISCUSSION
The FT-IR spectrum of Fe3O4@NCs/BF0.2 shows the
stretching vibrations of the OH group at 3,334 cm−1 and the
stretching vibrations of the C–O group appear at around
1,032 and 1,160 cm−1. In addition to the above-mentioned
bands, a broad band at 567 cm−1 corresponds to Fe/O
stretching vibrations in the Fe3O4 Lattice. Figure 2 repre-
In this work, Fe3O4@NCs/BF0.2 was prepared in several
steps. At first, NC was obtained from the acid hydrolysis of
cotton. In this step, the free OH groups in NC were increased
and could be used in the synthesis of NC-supported cata-
lysts. Fe3O4@nanocellulose was obtained simply through
coprecipitation of ferric and ferrous ions with ammonium
hydroxide in an aqueous solution containing NC. At the end,
preparation of Fe3O4@NCs/BF0.2 was done via mixing of
Fe3O4@nanocellulose and BF3.OEt2 at room temperature.
The OH groups in the NC act as a nucleophile and B–O–C
bonds were formed by the interaction between the BF3 and
the OH groups (Scheme 1).
The morphology and structure of the prepared
Fe3O4@NCs/BF0.2 composite were characterized through
FT-IR, vibrating sample magnetometer (VSM), X-ray dif-
fraction (XRD), XRF, Brunauer–Emmett–Teller (BET), field
emission scanning electron microscopy (FESEM), transmis-
sion electron microscopy (TEM), and thermal gravimetric
analysis (TGA) techniques. The FT-IR spectra of Fe3O4,
sents the FESEM and TEM images of Fe3O4@NCs/BF0.2
,
which were used to investigate the particle size and surface
morphology. This image indicates that the Fe3O4@
NCs/BF0.2 particles are on average below 20 nm.
The XRD patterns of Fe3O4, Fe3O4@NCs, and Fe3O4@
NCs/BF0.2 are shown in Figure 3. According to the XRD
patterns of Fe3O4@ NCs/BF0.2 (Figure 3a), a signal in 2θ
equal to 23 confirmed the existence of cellulose in its
FIGURE 1 (a) Fe3O4, (b) Nanocellulose, (c) Fe3O4@NCs, and
FIGURE 3 The XRD patterns of: (a) Fe3O4@NCs/BF0.2,
(d) Fe3O4@ NCs/BF0.2
(b) Fe3O4

MIRJALILI AND IMANI
3
(b)
(a)
FIGURE 4 Magnetization loops of (a) Fe3O4 and
(b) Fe3O4@NCs/BF0.2
structure. The signals in 2θ = 30, 36, 43, 54, 57, and 63 dem-
onstrate the existence of Fe3O4.
The magnetic properties of Fe3O4 and Fe3O4@NCs/BF0.2
were investigated at room temperature (300 K) using VSM
studies (Figure 4), no hysteresis loop and no remanence
were detected and also the coercivity value is zero for two
samples, suggesting typical superparamagnetic property at
room temperature. The amounts of saturation magnetization
for Fe3O4 and Fe3O4@NCs/BF0.2 are 50 and 23 emu/g,
respectively. Despite this significant decrease, the catalyst
can still be easily separated from the reaction mixture by
using an external magnet.
To investigate the elemental component of Fe3O4@
NCs/BF0.2, XRF analysis of the catalyst was done by com-
parison of its kilo counts per second (KCPS) of elements in
the catalyst with pure samples (NaF, H3BO3), (Table 1). The
amounts obtained for B and F are 3.496 g (0.32 mol) and
1.112 g (0.059 mol), respectively. Thus, the B:F ratio, in the
catalyst, is approximately 5:1.
The specific surface area of the catalyst was measured
using the BET theory (Figure 5a). The single point surface
area at P/Po = 0.0685 is 65.9890 m2/g and the BET surface
area is 74.2480 m2/g. The N2 adsorption isotherm of the cat-
alyst is depicted in Figure 5b.
FIGURE 5 (a) BET of Fe3O4@NCs/BF0.2 and (b) nitrogen
adsorption isotherms of Fe3O4@NCs/BF0.2
TGA-DTA analysis was performed to estimate thermal
stability of the Fe3O4@NCs/BF0.2 in the temperature range
of 26–814ꢀC (Figure 6). The TGA curve illustrates three
stages of weight loss. The first weight loss at 93ꢀC (5%
weight loss) is related to the removal of moisture from the
TABLE 1 XRF analysis of the catalyst and pure samples
Fe3O4@NCs/BF0.2
component B% F% KCPS B%
0.5 17.48 2.5
H3BO3
NaF
Elemental
KCPS F%
KCPS
B
F
3.496
—
—
—
FIGURE 6 Thermal gravimetric analysis patterns of Fe3O4@
NCs/BF0.2
—
1.112
1
—
—
45.25 40.7

4
MIRJALILI AND IMANI
catalyst. The next weight loss (52%) appears in the range of
100–670ꢀC and is related to the decomposition of cellulosic
units in the nanocomposite. Finally, the main weight loss
(6%) is observed in the range of 670–700ꢀC.
separated using an external magnet. Then, by adding water
to the residue, the pure products were obtained.
3.4 | Selected spectral data
3.4.1 | 2-(4-Methoxyphenyl)-2, 3-dihydro-1H-
3 | EXPERIMENTAL
3.1 | Materials and methods
perimidine (3b)
FTIR (ATR) ῡ/cm-13,362, 3,041, 1,592, 1,406, 1,239, 1,023, and
811; 1HNMR (DMSO-d6, 400 MHz): δ = 3.76 (s, 3H), 5.28 (s,
1H), 6.46 (d, J = 7.2 Hz, 2H), 6.65 (s, 2H), 6.96 (m, J = 6.8 Hz,
4H), 7.12 (t, J = 8.0 Hz, 2H), and 7.52 (d, J = 7.2 Hz, 2H).
All compounds were purchased from Aldrich, Merck, and
Fluka chemical companies. NCs and Fe3O4@nanocellulose
(Fe3O4@NCs) were synthesized via our previously reported
methods.[16–19] FT-IR spectra were run on a Bruker, Equi-
nox 55 spectrometer. A Bruker (DRX-400 Avance) NMR
was used to record the 1H NMR and 13C NMR spectra. The
XRD pattern was obtained using a Philips Xpert MPD dif-
fract meter equipped with a Cu Ka anode (k = 1.54 Aꢀ) in
the 2θ range from 10 to 80ꢀ. XRF analysis was done using a
Bruker, S4 Explorer instrument. VSM measurements were
performed using a VSM (Meghnatis Daghigh Kavir
Co. Kashan, Iran), a refrigerated centrifuge (Appendorf Cen-
trifuge 5417R) was used for the preparation of NC. Melting
points were determined using a Buchi melting point B-540
B.V.CHI apparatus. The FESEM image was obtained on a
Mira 3-XMU. The TEM image was obtained using a Philips
CM120 with a LaB6 cathode and an accelerating voltage of
120 kV. Quantitative elemental information (EDS) of
Fe3O4@NCs/BF0.2 was obtained using an EDS instrument
and Phenom pro X. TGA was conducted using a “STA 504”
instrument. The BET surface area of the catalyst was ana-
lyzed using a Micromeritics, Tristar II 3020 analyzer.
3.4.2 | 2-(2, 4-Dimethoxyphenyl)-2, 3-dihydro-
1H-perimidine (3c)
FTIR (ATR) ῡ/cm-13,358, 3,048, 1,597,1,417, 1,265, and 1,032;
1HNMR (DMSO-d6, 400 MHz): δ = 3.33 (s, 1H), 3.76 (s, 3H),
3.81 (s, 3H), 5.60 (s, 1H), 6.44 (s, 1H), 6.46 (d, J = 7.2 Hz, 2H),
6.55 (d, J = 6.8 Hz, 1H), 6.60 (s, 1H), 6.94 (d, J = 7.6 Hz, 2H),
7.12 (t, J = 8.0 Hz, 2H), and 7.45 (d, J = 8.4 Hz, 1H).
3.4.3 | 2-(4-Dimethylaminophenyl)-2,
3-dihydro-1H-perimidine (3d)
FTIR (ATR) ῡ/cm-13,334, 3,042, 1,590, 1,410, and 809;
1HNMR (DMSO-d6, 400 MHz): δ = 2.89 (s, 6H), 3.34
(s, 1H), 5.21 (s, 1H), 6.45 (d, J = 7.2 Hz, 2H), 6.57 (s,
1H), 6.75 (d, J = 6.8 Hz, 2H), 6.93 (d, J = 8 Hz, 2H),
7.11 (t, J = 8 Hz, 2H), and 7.39 (d, J = 7.2 Hz, 2H).
3.4.4 | 2-(3, 4-Dimethoxyphenyl)-2, 3-dihydro-
1H-perimidine (3e)
FTIR (ATR) ῡ/cm-13,347, 3,048, 1,593, 1,460, 1,261, 1,019,
and 859, 811; 1HNMR (DMSO-d6, 400 MHz): δ = 3.75 (s,
3H), 3.76 (s, 3H), 5.27 (s, 1H), 6.47 (d, J = 7.2 Hz, 2H), 6.66
(s, 1H), 6.97–7.15 (m, 7H), and 7.2 (s, 1H).
3.2 | Preparation of Fe3O4@NCs/BF0.2
In a beaker, 10 mL of dichloromethane was added to a
Fe3O4@NCs (0.5 g) and stirred at room temperature. Then,
0.5 mL BF3.OEt2 was added dropwise to a mixture and
stirred for 1 hr at room temperature. After this, the mixture
was filtered, washed with dichloromethane, dried at room
temperature, and the Fe3O4@NCs/BF0.2 catalyst was
obtained.
3.4.5 | 2-(4-Carboxyphenyl)-2, 3-dihydro-1H-
perimidine (3f)
FTIR (ATR) ῡ/cm-13,343, 3,051, 1,687, 1,592, 1,499, and
814; 1HNMR (DMSO-d6, 400 MHz): δ = 3.99(s, 1H), 5.42
(s, 1H), 6.49 (d, J = 7.2 Hz, 2H), 6.85 (s, 1H), 6.98 (d,
J = 8 Hz, 2H), 7.16 (t, J = 7.6 Hz, 2H), 7.62 (d, J = 8.4 Hz,
2H), 7.98 (d, J = 8 Hz, 2H), and 13 (s, 1H).
3.3 | General procedure for synthesis of
2,3-dihydro-1H-perimidines
Fe3O4@NCs/BF0.2 (0.03 g) as a catalyst was added to a
mixture of aromatic aldehyde (1.0 mmol) and
1,8-diaminonaphthalene (1.0 mmol). The mixture was stirred
at room temperature. After completion of the reaction (moni-
tored by TLC, n-hexane:diethylether [70:30]), the reaction
mixture was dissolved in acetone and the catalyst was
3.4.6 | 2-(4-Chlorophenyl)-2, 3-dihydro-1H-
perimidine (3g)
FTIR (ATR) ῡ/cm-13,387, 3,036, 1,595, 1,483, 1,086, and
812; 1HNMR (DMSO-d6, 400 MHz): δ = 5.35 (s, 1H), 6.47

MIRJALILI AND IMANI
5
(d, J = 6.8, 2H), 6.79 (s, 1H), 6.97 (d, J = 8.0 Hz, 2H), 7.13
(t, J = 7.6 Hz, 2H), 7.16 (s, 1H), 7.48 (d, J = 7.9 Hz 2H),
and 7.60 (d, J = 7.9 Hz, 2H).
3.4.8 | 2-(3-Nitroophenyl)-2, 3-dihydro-1H-
perimidine (3i)
FTIR (ATR) ῡ/cm-13,343, 3,044, 1,593, 1,519, 1,343, and
1,412; 1HNMR (DMSO-d6, 400 MHz): δ = 5.6 (s, 1H), 6.50
(d, J = 7.2 Hz, 2H). 6.98 (s, 1H), 7.01 (d, J = 8.4 Hz, 2H),
7.15 (t, J = 7.6 Hz, 2H), 7.62 (t, J = 8.0 Hz, 1H), 7.97 (d,
J = 7.6 Hz, 1H), 8.18 (d, J = 6.8 Hz, 1H), and 8.37 (s, 1H).
3.4.7 | 2-(2-Nitroophenyl)-2, 3-dihydro-1H-
perimidine (3h)
FTIR (ATR) ῡ /cm-13,365, 3,068, 1,597, 1,511, 1,345, and
1,411; 1HNMR (DMSO-d6, 400 MHz): δ = 3.34 (s, 1H),
5.79 (s, 1H), 6.51 (d, J = 7.2, 2H). 6.8 (s, 1H), 7.01 (d,
J = 8.4 Hz, 2H), 7.16 (t, J = 8.0 Hz, 1H), 7.61 (t, J = 8.0 Hz,
2H), 7.75 (t, J = 6.8 Hz, 1H), 7.89 (d, J = 8.0 Hz, 1H), and
8.02 (d, J = 8.0 Hz, 1H).
3.4.9 | 2-(4-Nitroophenyl)-2, 3-dihydro-1H-
perimidine (3j)
FTIR (ATR) ῡ/cm-13,365, 3,068, 1,595, 1,410, 1,511,
1,343, and 811; 1HNMR (DMSO-d6, 400 MHz): δ = 3.34
TABLE 2 The reaction of 1,8-diaminonaphthalene (1.0 mmol) and benzaldehyde (1.0 mmol), in the presence of Fe3O4@NCs/BF0.2 under
various conditions
Entry
1
Catalyst (g)
Condition
r.t.b
r.t.b
r.t.b
r.t.b
r.t.b
r.t.b
Solvent
Time (min)
Yield (%)a
53
—
—
20
20
20
20
5
2
Fe3O4 (0.06)
—
64
3
Fe3O4@NCs (0.06)
—
50
4
Fe3O4@NCs/BF0.2 (0.015)
Fe3O4@NCs/BF0.2 (0.03)
Fe3O4@NCs/BF0.2 (0.05)
Fe3O4@NCs/BF0.2 (0.03)
Fe3O4@NCs/BF0.2 (0.03)
Fe3O4@NCs/BF0.2 (0.03)
Fe3O4@NCs/BF0.2(0.03)
Fe3O4@NCs/BF0.2 (0.03)
Fe3O4@NCs/BF0.2 (0.03)
Fe3O4@NCs/BF0.2 (0.03)
Fe3O4@NCs/BF0.2 (0.03)
Fe3O4@NCs/BF0.2(0.03)
Fe3O4@NCs/BF0.2 (0.03)
Fe3O4@NCs/BF0.2 (0.03)
Fe3O4@NCs/BF0.2(0.03)
Fe3O4@NCs/BF0.2 (0.03)
—
82
5
—
98
6
—
20
5
94
7
Microwave
Mixer mill
Ultrasound bath
Ultrasound
Ultrasound
Ultrasound
Ultrasound
Ultrasound
Ultrasound
Ultrasound
r.t.b
—
66
8
—
5
70
9
—
5
93
10
11
12
13
14
15
16
17
18
19
EtOH
5
45
H2O
5
71
H2O:EtOH (1:1)
PEG 400
Acetone
MeOH
CH2Cl2
H2O
5
80
5
83
5
81
5
81
5
79
180
180
180
40
r.t.b
r.t.b
EtOH
58
H2O:EtOH (1:1)
25
aIsolated yield.
bRoom temperature.

6
MIRJALILI AND IMANI
(s, 1H), 5.48 (s, 1H), 6.49 (d, J = 7.2 Hz, 2H). 6.98 (d,
J = 8.4 Hz, 3H), 7.15 (t, 2H, J = 7.6 Hz), 7.78 (d,
J = 8.4 Hz, 2H), and 8.21 (d, J = 8.8 Hz, 2H).
3.5 | Catalytic activity of Fe3O4@NCs/BF0.2
After characterization of the catalyst, the catalytic activity of
Fe3O4@NCs/BF0.2 was investigated for the synthesis of
2,3-dihydro-1H-perimidine derivatives. 2-phenyl-2,3-dihydro-
1H-perimidine was synthesized via condensation of
1,8-diaminonaphthalene (1.0 mmol) with benzaldehyde
(1.0 mmol) as model reaction. To optimize the reaction condi-
tions, the effects of several parameters such as catalyst
amount, solvent, and reaction time were studied (Table 2).
According to Table 2, the best condition for the reaction is a
solvent-free condition using 0.03 g of Fe3O4@NCs/BF0.2 as
an efficient catalyst at room temperature (Table 2, entry 21).
Based on optimal reaction conditions, 2,3-dihydro-
1H-perimidine derivatives were synthesized using the
two-component condensation of various aldehydes
(1.0 mmol) and 1,8-diaminonaphthalene (1.0 mmol)
(Table 3). All synthesized compounds were identified
using melting point, FT-IR, 1H-NMR, and 13C-NMR
spectroscopy.
3.4.10 | 2-(2, 3-Dichlorophenyl)-2, 3-dihydro-
1H-perimidine (3k)
FTIR (ATR) ῡ/cm-13,347, 3,047, 1,595, 1,404, 1,039,
751, and 645; 1HNMR (DMSO-d6, 400 MHz): δ = 3.35 (s,
1H), 5.77 (s, 1H), 6.5 (d, J = 6.8 Hz, 2H), 6.83 (s, 1H), 7.02
(d, J = 8.0 Hz, 2H), 7.17 (t, J = 7.2 Hz, 2H), 7.43
(t, J = 7.6 Hz, 1H), and 7.67 (d, J = 6.8 Hz, 2H).
3.4.11 | 2-(2, 3-Dimethoxyphenyl)-2,
3-dihydro-1H-perimidine (3l)
FTIR (ATR) ῡ/cm-13,355, 3,048, 1,595, 1,417, 1,260,
1,060, 751, and 638; 1HNMR (DMSO-d6, 400 MHz):
δ = 3,79 (s, 3H), 3.82 (s, 3H), 5.65 (s, 1H), 6.48 (d,
J = 7.2 Hz, 2H), 6.55 (s, 1H), and 6.96–7.16(m, 9H).
a
TABLE 3 Synthesis of 2,3-dihydro-1H-perimidine derivatives (IIIa–l) in the presence of Fe3O4@NCs/BF0.2
M.P.
Entry
R
Product
3a
Time (min)
Yield (%)b
Found
Reported [ref.]
103–105[20]
160–162[7]
1
H
5
98
91
75
86
92
99
96
94
96
99
88
85
101–103
156–158
205–207
50–52
2
4-OMe
2,4-(OMe)2
4-NMe2
3,4-(OMe)2
4-COOH
4-Cl
3b
3c
15
15
15
15
10
10
12
10
10
15
20
[21]
3
—
4
3d
3e
51–53[20]
206–207[7]
5
202–203
200–202
153–155
157–159
189–191
199–201
165–167
102–103
[21]
6
3f
—
7
3g
154–156[20]
158–160[5]
188–190[5]
201–202[9]
8
2-NO2
3h
3i
9
3-NO2
10
11
12
4-NO2
3j
[21]
2,3-(Cl)2
2,3-(OMe)2
3k
3l
—
[21]
—
aReaction conditions: 1,8-diaminonaphthalene (1.0 mmol), aldehyde (1.0 mmol), and Fe3O4@NCs/BF0.2 (0.03 g).
bIsolated yield.

MIRJALILI AND IMANI
7
TABLE 4 Comparison of the Fe3O4@NCs/BF0.2 catalyst with reported catalysts for the synthesis of 2,3-dihydro-1H-perimidine derivatives
Entry
Catalyst
Condition
r.t.
Solvent
EtOH
Time
24 hr
Yield (%)
52
Ref.
[22]
1
Acetic acid (a few drops)
NSSAa (2 mg)
[7]
2
r.t.
EtOH
50 min
10 min
25 min
12 hr
84
[6]
3
Cu(NO3)2.6H2O (5 mol%)
CuY zeolite (0.002 g)
FePO4 (0.01 g)
r.t.
EtOH
83
[9]
4
r.t.
EtOH
81
[5]
5
r.t.
EtOH
80
[22]
[23]
[8]
6
MNPs-TBSAb (20 mg)
50ꢀC
EtOH/H2O(1:1)
EtOH
25 min
40 min
45 hr
90
7
Iodine (7 mol%)
r.t.
84
8
NaY zeolite (0.20 g)
Yb(OTf)3 (0.1 eq.)
Na2S2O5 (1.9 g)
r.t.
EtOH
70
[24]
[25]
9
r.t.
Acetonitrile
EtOH/H2O(1:1)
—
1 hr
88
10
11
Reflux
—
1 hr
95
Fe3O4@NCs/BF0.2 (0.03 g)
5 min
98
This work
aNanosilica sulfuric acid.
bTriazinediyl bis-sulfamic acid-grafted magnetite nanoparticles.
The comparison of data of the efficiency of
Fe3O4@NCs/BF0.2 with that of other reported catalysts for
the synthesis of 2-phenyl-2,3-dihydro-1H-perimidines is
indicated in Table 4. We have observed good and high
yields of products under very mild and green conditions
using Fe3O4@NCs/BF0.2. The results show that with
Fe3O4@NCs/BF0.2, 2,3-dihydro-1H-perimidine derivatives
can be synthesized as 2-phenyl-2,3-dihydro-1H-perimidines
in a shorter time and under green conditions with higher
yields. Other advantages of Fe3O4@NCs/BF0.2 as a catalyst
are environmental friendliness, biodegradation, reusability,
and easy separation with an external magnet.
The reusability of the catalyst was also investigated on the
model reaction. The magnetic catalyst was separated using an
external magnet, washed with acetone, dried at room tempera-
ture, and reused for subsequent reactions. It was observed that
the recovered biocatalyst could be used at least four times
with little decrease in its catalytic activity (Figure 7).
The proposed mechanism for the synthesis of 2-phenyl-2,-
3-dihydro-1H-perimidine in the presence of Fe3O4@
NCs/BF0.2 is shown in Scheme 2. At first, Fe3O4@NCs/BF0.2
as Lewis acid attacked the carbonyl group of aldehyde. Then,
SCHEME 2 Proposed mechanism for the synthesis of 2-phenyl-
2,3-dihydro-1H-perimidines
nucleophilic attack of 1,8-diaminonaphthalene on activated
aldehyde generated imine intermediate (a). The nucleophilic
attack of the second amino group on the activated imine inter-
mediate afforded intermediate (b). Finally, with the transfer of
proton, the product is produced.
4 | CONCLUSIONS
In summary, Fe3O4@NCs/BF0.2 was successfully synthe-
sized and characterized. It was applied for the synthesis of
FIGURE 7 Catalyst recycling experiments

8
MIRJALILI AND IMANI
[10] H. Alinezhad, M. Zare, J. Chil. Chem. Soc. 2013, 58, 1840.
of 2,3-dihydro-1H-perimidine derivatives through the
reaction of 1,8-diaminonaphthalene and aromatic alde-
hydes under solvent-free conditions at room temperature.
This method offers several advantages including easy
work-up, excellent yields, short reaction time, and envi-
ronmental friendliness.
[11] M. Jorfi, E. J. Foster, J. Appl. Polym. Sci 2015, 132, 41719.
[12] X. An, Y. Long, Y. Ni, Carbohyd. Polym. 2017, 156, 253.
[13] H. Wei, K. Rodriguez, S. Renneckar, P. J. Vikesland, Environ.
Sci. Nano. 2014, 1, 302.
[14] N. Azgomi, M. Mokhtary, J. Mol. Catal. A: Chem. 2015, 398, 58.
[15] X. Zheng, S. Luo, L. Zhang, J. P. Cheng, Green Chem. 2009,
11, 455.
[16] S. Azad, B. F. Mirjalili, RSC Adv. 2016, 6, 96928.
[17] N. Salehi, B. F. Mirjalili, RSC Adv. 2017, 7, 30303.
[18] S. Azad, B. F. Mirjalili, Mol. Divers 2018 in press.
[19] B. F. Mirjalili, F. Aref, Res. Chem. Intermed. 2018, 44, 4519.
[20] M. A. Bodaghifard, S. A. sadbegi, Z. Bahrami, J. Iran. Chem.
Soc. 2017, 14, 365.
ACKNOWLEDGMENTS
The Research Council of Yazd University is gratefully
acknowledged for the financial support for this work.
[21] A. Bamoniri, B. F. Mirjalili, S. Saleh, RSC Adv. 2018, 8, 6178.
[22] K. M. Salih, H. Azeez, J. Res. Pharm. Biotechnol. 2014, 5, 1.
[23] A. Mobinikhaledi, F. Sasani, A. Hamta, S. M. Shariatzadeh, Bulg.
Chem. Commun. 2013, 45, 353.
[24] C. K. Wu, T. J. Liou, H. Y. Wei, P. S. Tsai, D. Y. Yang, Tetrahe-
dron 2014, 70, 8219.
ORCID
Bi Bi Fatemeh Mirjalili https://orcid.org/0000-0002-6588-
4041
REFERENCES
[25] A. Maquestiau, L. Berte, A. Mayence, J. J. V. Eynde, Synth.
Commun. 1991, 21, 2171.
[1] T. A. Farghaly, E. M. Abbas, Molecules 2014, 19, 740.
[2] M. H. Krishna, P. Thriveni, J. Chem. Pharm. Res. 2016, 8, 809.
[3] D. R. Panchasara, S. Pande, E-J. Chem. 2009, 6, 91.
[4] M. M. Belmonte, E. C. Escudero-Adán, J. Benet-Buchholz,
R. M. Haak, A. W. Kleij, Eur. J. Org. Chem. 2010, 25, 4823.
[5] F. K. Behbahani, F. M. Golchin, J. Taibah Univ. Sci. 2017,
11, 85.
SUPPORTING INFORMATION
Additional supporting information may be found online in
the Supporting Information section at the end of this article.
[6] A. Mobinikhaledi, P. J. Steel, Synth. React. Inorg. Met. Org.
Chem. 2009, 39, 133.
[7] A. Mobinikhaledi, H. Moghanian, F. Sasani, Int. J. Green
Nanotechnol. Phys. Chem. 2010, 2, 47.
[8] A. Mobinikhaledi, N. Forughifar, N. Bassaki, Turk. J. Chem.
2009, 33, 555.
[9] M. Kalhor, N. Khodaparast, Res. Chem. Intermed. 2015, 41,
3235.
How to cite this article: Mirjalili BBF, Imani M.
Fe3O4@NCs/BF0.2: A magnetic bio-based
nanocatalyst for the synthesis of 2,3-dihydro-1H-
perimidines. J Chin Chem Soc. 2019;1–8. https://doi.
org/10.1002/jccs.201900004