Copper(I) complex of 1,3-DimethylBarbituric acid modified SBA-15 and its catalytic role for the synthesis of 2,3-Dihydroquinazolin-4(1H)-ones and Imidazoles

Article abstract of DOI:10.1002/aoc.3843

An efficient one-pot method for synthesis of 2,3-dihydroquinazolin-4(1H)-ones and tri/tetra substituted-1H-imidazoles has been accomplished in the presence of catalytic amounts of Cu(I)-1,3-dimethylbarbituric acid modified SBA-15 as heterogeneous catalyst with good to excellent yields. The catalyst is reusable and can be applied several times without any decrease in product yield. The synthesized catalyst was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), thermal gravimetric analysis (TGA), N₂ adsorption/desorption isotherms (BET), Fourier transform infrared spectroscopy (FT-IR) and atomic absorption spectroscopy (AAS).

Full text of DOI:10.1002/aoc.3843

Received: 1 January 2017
DOI: 10.1002/aoc.3843
Revised: 6 March 2017
Accepted: 18 March 2017
F U L L PA P E R
Copper(I) complex of 1,3‐DimethylBarbituric acid modified SBA‐
15 and its catalytic role for the synthesis of 2,3‐Dihydroquinazolin‐
4(1H)‐ones and Imidazoles
Maryam Hajjami1
| Farshid Ghorbani2 | Zakieh Yousofvand1
1 Department of Chemistry, Faculty of
Science, Ilam University, PO Box 69315516,
Ilam, Iran
2 Department of Environment, Faculty of
Natural Resource, University of Kurdistan,
PO 66177‐15177, Sanandaj, Iran
An efficient one‐pot method for synthesis of 2,3‐dihydroquinazolin‐4(1H)‐ones
and tri/tetra substituted‐1H‐imidazoles has been accomplished in the presence of
catalytic amounts of Cu(I)‐1,3‐dimethylbarbituric acid modified SBA‐15 as
heterogeneous catalyst with good to excellent yields. The catalyst is reusable and
can be applied several times without any decrease in product yield. The
synthesized catalyst was characterized by scanning electron microscopy (SEM),
X‐ray diffraction (XRD), energy dispersive X‐ray spectroscopy (EDS), thermal
gravimetric analysis (TGA), N2 adsorption/desorption isotherms (BET), Fourier
transform infrared spectroscopy (FT‐IR) and atomic absorption spectroscopy
(AAS).
Correspondence
M. Hajjami, Department of Chemistry,
Faculty of Science, Ilam University, P.O. Box
69315516, Ilam, Iran.
Email: mhajjami@yahoo.com;
m.hajjami@ilam.ac.ir
KEYWORDS
2,3‐dihydroquinazolin‐4(1H)‐ones, cu‐barbituric acid modified SBA‐15, imidazoles, multicomponent
reactions, one‐pot reactions
1 | INTRODUCTION
moieties.[10–14] 2,3‐dihydroquinazolin‐4(1H)‐ones have many
applications in the pharmaceutical activities for example
In recent years, nanostructure mesoporous materials such as
MCM‐41 and SBA‐15 with unique properties were used as
templates for the syntheses of shape‐selective new materials.
These materials are synthesized via the polymerization of sil-
ica around periodic cationic amphiphiles such as cetyl
trimethylammonium bromide as a template (MCM‐41) and
neutral block copolymer such as P123 (SBA‐15). Santa
Barbara Amorphous (SBA‐15) possess a hexagonal array of
uniform pores is similar to structure MCM‐41 and has also
the larger pores (adjustable pore size from 3 to 30 nm),
thicker pore walls and greater stability in aqueous solutions
compared to MCM‐41. So SBA‐15 provide a high potential
for nanomaterial chemosensors and adsorbent, catalysis and
other applications.[1–9] Besides, the internal surfaces of these
mesoporous silica materials have a large number of hydroxyls,
which reaction of these silanol groups with various
alkoxysilanes has been widely used for preparing functional-
ized SBA‐15 by covalent grafting with various organic
antibacterial, antitumor, antifungle,[15] altanserin and nitro
altanserin.[16]Yet several catalysts have been reported for the
synthesis of 2,3‐dihydroquinazolinones such as silicasulfuric
acid.[17] cellulose‐SO3H,[18] l‐pyrrolidine‐2‐carboxylicacid‐4‐
hydrogen sulfate supported on silica gel,[19] glucosulfonic acid
supported on Fe3O4 nanoparticles[20] and etc. Also synthesis of
imidazoles play a major role in the biological activity[21] such
as inhibitors of p38 MAP kinase, B‐Raf kinase,[22] glucagon
receptors and plant growth regulators.[23] The number of
methods have been reported for the synthesis of tri/tetra
[24]
substituted‐1H‐imidazoles such as MoO3/SiO2,
silica‐
bonded propylpiperazine N‐sulfamic acid,[25] Wells–Dawson
heteropolyacid supported on silica[26] and etc. In this work
for the synthesis of catalyst, the copper (I) complex of 1,3‐
dimethylbarbituric acid is grafted to mesoporous silica
SBA‐15 using 3‐aminopropyltriethoxysilane (APTES) as
linker to the surface. There are several advantages for this
catalytic system such as soft acidic conditions, short reaction
Appl Organometal Chem. 2017;e3843.
wileyonlinelibrary.com/journal/aoc
Copyright © 2017 John Wiley & Sons, Ltd.
1 of 9
https://doi.org/10.1002/aoc.3843

2 of 9
HAJJAMI ET AL.
times, need for cheap reactant, purity yields, easy separation
of yields and reusable catalysts compared to other systems.
added drop wise to 4.8 g of SBA‐15 in 96 mL n‐hexane
and the reaction mixture was stirred under reflux condition
for 24 h at N2 atmosphere. Then the obtained white solid
was filtered and washed with n‐hexane and dried at room
temperature for 24 h to obtain aminofunctionalized SBA‐15
(SBA‐15‐nPr‐NH2).[28] Then 1,3‐dimethylbarbituric acid
and aminofunctionalized mesoporous with ratio 2 mmol:1 g
were added to absolute ethanol in the presence of 0.3 ml of
acetic acid and refluxed at 80 °C under N2 atmosphere for
48 h. Then the mixture was filtered, washed with ethanol
and dried at 60 °C, resulting is a yellow sediment. Finally
CuCl was added to this sediment (with ratio 3 mmol:1 g) in
acetonitrile and mixture was stirred for 24 h at room temper-
ature. Finally the resulting product was washed with acetoni-
trile and water to remove excess of Cu (I) (Scheme 1).
2 | EXPERIMENTAL
2.1 | Materials and instrumentation
All reagents and used materials in this work were purchased
from Sigma Aldrich and Merck chemical companies, and
were used without any further purification. All the melting
points were recorded by open capillary method and are
uncorrected. IR spectra were recorded in KBr. 2,3‐
dihydroquinazolin‐4(1H)‐one and tri/tetra substituted imidaz-
ole derivatives were characterized by 1H and 13C NMR
spectra (1H NMR, 400 MHz, 13C NMR, 100 MHz).TGA
was used with a heating rate of 10 °C/min in air and the
samples were heated from room temperature to 850 °C.
XRD patterns were recorded using a Cu Kα radiation source
with wave length 1.54A°. In N2 adsorption/ desorption all of
the samples were degassed at 100 °C for 5 h before analysis
and range of relative pressures (p/p0) was 0.028–0.989.
2.4 | General procedure for the synthesis of
2,3‐dihydroquinazolin‐4(1H)‐ones
A mixture of aldehyde (1 mmol), 2‐aminobezamide (1 mmol)
and copper (I) modified‐SBA‐15 (0.03 g) was stirred at room
temperature in dichloromethane (2 mL). After completion of
the reaction, as indicated by TLC (aceton:n‐hexane 2:8), the
product was extracted with CH2Cl2 and the catalyst was
separated by simple filtration. Finally, the organic solvents
were evaporated, and products were obtained in 80–98%
yield. Then the crude product was purified by recrystalliza-
tion from ethanol.
2.2 | Synthesis of SBA‐15(isothermal)
About 5.34
(propyleneglycol)‐block‐poly
g
of poly (ethyleneglycol)‐block‐poly
(ethyleneglycol) triblock
copolymer, P123, was dissolved in 100 mL of solution
0.3 M of HCl under stirring for 12 h at room temperature.
After dropwise addition of 8.29 g of tetraethyl orthosilicate
(TEOS), the reaction mixture was stirred for 24 h at 35 °C.
The resulting solution was transferred into a teflon bottle
and heated to 100 °C for 48 h. The resulting white powder
was filtered without washing, and was dried at 100 °C for
24 h. The white powder was soxleth extraction at 80 °C with
a mixture of 80 ml of ethanol and 1.5 ml of concentrated
hydrochloric acid for 24 h. Finally, the sample was calcined in
an air atmosphere at 550 °C with a heating rate of 2 °C/min
and for 5 h.[27]
2.5 | General procedure for the synthesis of
tri/tetra substituted‐1H‐imidazoles
For the synthesis of 2,4,5‐tri‐substituted imidazoles, a mix-
ture of benzil (1 mmol), an aromatic aldehyde (1 mmol),
ammonium acetate (4.5 mmol) and catalyst (0.01 g) and for
the synthesis of 1,2,4,5‐tera‐substituted imidazoles, benzil
(1 mmol), aromatic aldehyde (1 mmol), a primary amine
(1 mmol), ammonium acetate (4.5 mmol) and catalyst
(0.01 g) was heated in the oil bath at 100 °C for the certain
period of time. The reaction was monitored by TLC. Upon
completion, the reaction mixture was cooled to room temper-
ature, dichloromethane was added and filtered. The product
was extracted with CH2Cl2 and the catalyst was separated
2.3 | Synthesis of copper (I) modified‐SBA‐15
First for functionalization of SBA‐15 by 3‐aminopro
pyltriethoxysilane, 4.8 g 3‐aminopropyltriethoxysilane was
SCHEME 1 Preparation of copper (I)
modified‐SBA‐15 (catalyst)

HAJJAMI ET AL.
3 of 9
by simple filtration, then recrystallized from absolute ethanol
to give pure substituted imidazole product.
the synthesis of tri/tetra substituted imidazoles and
2,3‐dihydroquinazolin‐4(1H)‐ones.
2.5.1 | Characterization data of selected
3.1 | Catalyst characterization
3.1.1 | X‐ray diffraction
Figure 1 shows XRD patterns of the synthesized SBA‐15 and
catalyst. Both materials showed well‐resolved peaks with
very intense diffraction peaks that can be indexed as (100),
(110), and (200) reflections associated with a hexagonal
compounds
2‐(4‐chlorophenyl)‐4,5‐diphenyl‐1H‐imidazole (1b)
1
M.p.:258–259 °C. HNMR (400 MHz CDCl3): δ = 9.48 (s,
1H), 7. 87–7.84 (d, 2H), 7.58–7.29 (m, 12H) ppm. 13C
NMR (100 MHz CDCl3): δ = 144.9, 134.7, 129.1, 128.7,
128.4, 127.8, 126.5 ppm. FT‐IR‐ATR: = 3413, 3063,
2838, 1635, 1481, 1323, 1152, 830, 695 cm−1
.
1‐(4‐chlorophenyl)‐2‐(4‐chlorophenyl)‐4,5‐diphenyl‐1H‐
imidazole (1j)
M.p.: 191–193 °C.1H–NMR (CDCl3, 400 MHz): δ = 7.91–
7.59 (d, 1H), 7.40–7.37 (d, 1H), 7.35–7.14 (m, 5H), 7.01–
6.98 (d, 1H) ppm. 13C NMR (100 MHz CDCl3): δ = 145.8,
138.7, 135.5, 134.6, 134.5, 134.1, 131.1, 131.0, 130.2,
129.6, 128.8, 128.7, 128.6, 128.4, 128.3, 127.4, 126.9 ppm.
2‐(4‐chlorophenyl)‐2,3‐dihydroquinazolin‐4(1H)‐one (2b)
M.p.: 201–202 °C, 1HNMR (400 MHz, CDCl3):
δ = 7.99–7.97 (d, 1H), 7.60–7.29 (m, 5H), 6.97–6.93
(t, 1H), 6.72–6.70 (d, 1H), 5.93 (s, 1H), 5.78 (s, 1H),
4.39 (s, 1H) ppm. 13C NMR (100 MHz CDCl3):
δ = 164.6, 147.0, 137.1, 136.1, 134.1, 129.4, 128.9,
128.8, 120.0, 115.6, 114.7, 68.5 ppm.
FIGURE 1 XRD patterns of SBA‐15 and catalyst
2‐(4‐Ethoxyphenyl)‐2,3‐dihydroquinazolin‐4(1H)‐one (2j)
M.p.: 163–166 °C,[1]HNMR (400 MHz, CDCl3):
δ = 7.98–7.96 (d, 1H), 7.57–7.51 (d, 2H), 7.38–7.34 (t,
1H), 6.98–6.90 (q, 3H), 6.70–6.69 (d, 1H), 5.87 (s, 1H),
5.82 (s, 1H), 4.25–4.07 (q, 2H), 1.52–1.29 (t, 3H) ppm. 13C
NMR (100 MHz CDCl3): δ = 164.9, 160.3, 147.4, 134.0,
130.4, 128.8, 128.7, 119.6, 115.7, 115.1, 114.6, 68.7, 63.7,
14.8 ppm.
3 | RESULT AND DISCUSSION
In continuation of our studies on synthesis of new hetero-
geneous catalyst and its applicationsin organic reac-
tions,[29–31] Cu(I)‐1,3‐dimethylbarbituric acid modified
SBA‐15 was synthesized and characterized by a variety of
physico‐chemical techniques. Herein we depict the prepara-
tion of a new heterogenised catalyst by functionalization of
SBA‐15with 3‐aminopropyl triethoxy silane, subsequent
immobilization of 1,3‐dimethylbarbituric acid group on
the synthesized SBA‐15‐ nPr‐NH2 and subsequent to that
event copper(I) complexed with 1,3‐dimethylbarbituric acid.
Resulting Cu (I)‐1,3‐dimethylbarbituric acid modified
SBA‐15 was applied as a new heterogeneous catalyst for
FIGURE 2 The IR spectra for SBA‐15 (a), SBA‐15‐ nPr‐NH2 (b),
SBA‐15‐1,3‐dimethyl barbituric acid (c), cu(I)‐1,3‐dimethylbarbituric
acid modified SBA‐15 (catalyst) (d)

4 of 9
HAJJAMI ET AL.
TABLE 1 Textural properties of synthesized materials obtained by
nitrogen adsorption–desorption analysis
space group symmetry P6mm. These patterns indicating that
the ordered hexagonal mesoporous structure of SBA‐15
retains intact during treatment with organic group. Some loss
in the intensity of the peaks was observed that
functionalization occurring mainly inside the mesopore chan-
nels. Moreover a unit cell parameter, a0, of 100.06 Å was
obtained for SBA‐15.
a
Sample
name
SBET
DBJH
(nm)
V
Wall diam
(nm)
Total
(cm3.g−1
)
(m2.g−1
)
SBA‐15
874
355
6.168
6.097
1.049
0.559
3.84
4.18
Catalyst
aCalculated from the desorption branch of the N2 isotherm by using the BJH
method.
3.1.2 | Ft‐ IR
The IR spectra for SBA‐15 (a), SBA‐15‐nPr‐NH2 (b),
SBA‐15‐1,3‐dimethylbarbituric
acid
(c),
Cu(I)‐1,3‐
dimethylbarbituric acid modified SBA‐15 (catalyst) (d), are
shown in Figure 2 in the all spectra the formation of the
Si–O–Si skeleton is evidenced by the bands located at about
1080 cm−1(ʋas, Si–O) and 806 cm−1(ʋs, Si–O), also the peaks
at above 3400 cm−1, which are assigned to O–H stretching of
the surface silanols of the SBA‐15. In the spectra of SBA‐15‐
nPr‐NH2 (b), the peak at 1513 and1629cm−1 can be assigned
to the amine functionality (N–H bending vibration). Beside
in the spectra of c and d, the presence of a series of bands
FIGURE 3 The thermo gravimetric analysis (TGA) curves of SBA‐
15, SBA‐15‐NH2 and catalyst
FIGURE 4 The N2 adsorption/desorption isotherm for SBA‐15 and
catalyst
FIGURE 5 SEM images of SBA‐15 (a) and catalyst (B)

HAJJAMI ET AL.
5 of 9
at around 2889‐3036 cm−1due to the vibrations of methy-
lene‐(CH2)3‐ and aliphatics –CH3 in the 1,3‐
dimethylbarbituric acid.
the removal of physically adsorbed water and surface
hydroxyl group. The weight loss of about 2.94%. The
weight loss (4.00%) between 135 and 835 °C is attributed
mainly to the condensation of silanol groups and removal
of chemically adsorbed water. SBA‐15‐NH2 shows four‐step
weight loss behavior. Weight loss of SBA‐15‐NH2 appears
about 10.77% at 105–586 °C, which is contributed to the
thermal decomposition of the 3‐aminopropyl trietoxysilan
groups (equivalent 0.49 mmol). Also catalyst shows four‐
step weight loss behavior, the weight loss is 16.5% at
135–709 °C that is due to decompose of the organic mate-
rials. On the basis of these results, the well grafting of
APTES and 1,3‐dimethylbarbituric acid groups on the
SBA‐15 is verified.
3.1.3 | Thermo gravimetric analysis (TGA)
The thermo gravimetric analysis (TGA) curves of SBA‐15,
SBA‐15‐NH2 and catalyst show the mass loss of the organic
materials as they decompose upon heating (Figure 3). The
initial weight loss from the SBA‐15 (<135 °C) is due to
3.1.4 | N2 adsorption–desorption isotherm
The N2 adsorption/desorption isotherm for SBA‐15and
catalyst samples are shown in Figure 4. Both isotherm
display type IV isotherms withH1‐type hysteresis loops at
high relative pressure according to the IUPAC classifica-
tion.[7] Also the Brunauer–Emmett–Teller surface area
(SBET), the Barret‐Joyner–Halenda average pore diameter
(DBJH) and the total pore volumes (Vtotal) of synthesized
samples are summarized in Table 1. Obtained results revealed
that the surface area and pore volume of SBA‐15 are high
FIGURE 6 Energy dispersive X‐ ray spectroscopy (EDS) for the
catalyst
TABLE 2 Results of optimize the amount of catalyst, amount of ammoniumacetate, temperature and solvent in the synthesis of tri substituted
imidazolesa
Entry
Amount of catalyst (g)
Amount of ammonium acetate (mmol)
Temperature (°C)
Solvent
Yieldb (%)
1
0.02
0.01
0.005
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
3
100
100
100
100
80
Solvent‐ free
Solvent‐ free
Solvent‐ free
Water
93
98
80
0
2
3
4
5
Aceto nitrile
Ethanol
0
6
78
0
7
40
Dichloromethane
Solvent‐ free
Ethyl acetate
Solvent‐ free
Solvent‐ free
Solvent‐ free
Solvent‐ free
Solvent‐ free
Solvent‐ free
Solvent‐ free
0
8
100
77
98
0
9
10
11
12
13
14
15
16
80
5
100
130
100
100
100
100
98
85
73
82
98
98
4
4.5
5
aReaction conditions: 4‐colorobenzaldehyde(1 mmol), benzil (1 mmol) and time 1 h.
byields after purification

6 of 9
HAJJAMI ET AL.
which is typical of mesoporous materials. After
functionalization, a decrease in the SBET, DBJH and Vtotal
was observed that can be easily interpreted due to the fact that
the presence of pendant group on the pour surface that
partially blocks the adsorption of nitrogen molecules. The
wall thickness of SBA‐15 was 3.84 Å where calculated by
the following equation.[31]
wallthickness ¼ a0−DBJH
ꢀ
ꢁ
2d1
0
0
pffiffi
Where unit‐cell parameter a0 ¼
determined from
3
small‐angle XRD analysis and DBJH calculated from the
desorption branch of the N2 isotherm by using the BJH
method.
3.1.5 | Scanning electron microscopy (SEM)
TABLE 3 Results of optimize the amount of catalyst and solvent in
the synthesis of 2,3‐dihydroquinazolin‐4(1H)‐onesa
Figure 5 shows the SEM micrographs of SBA‐15 and cata-
lyst. As can be seen in the micrograph of the catalyst show
uniform particle size distribution and particles with diameter
about 1 μm, retaining the well‐defined wheat‐like macro-
structure clusters of pure SBA‐15.
Entry Amount of catalyst (g)
Solvent
Yieldb (%)
1
2
3
4
5
6
7
8
9
10
0.05
0.03
0.02
0.01
0.03
0.03
0.03
0.03
0.03
0.03
Dichloromethane
Dichloromethane
Dichloromethane
Dichloromethane
Water
98
97
90
89
86
40c
97
67
84
0
3.1.6 | Atomic absorption spectroscopy (AAS)
Based on atomic absorption spectroscopy, the amounts of
copper(I) in Cu(I)‐1,3‐dimethylbarbituric acid modified
SBA‐15was 0.737 mmol/g. Also to investigate leaching of
the Cu species, experiment was carried out in reaction of
3‐nitro benzaldehyde with 2‐aminobezamide in the synthe-
sis of 2,3‐dihydroquinazolin‐ 4(1H)‐ ones. In representative
test, the solid catalyst was filtered out and the filtrate was
analyzed Copper content using AAS. The amounts of Cu
(I) obtained 0.645 mmol/g and a decrease of 9% was
observed.
Ethanol
Dichloromethane
n‐ hexane
Ethylacetate
Solvent‐ free
aReaction conditions: 3‐nitro benzaldehyde(1 mmol), 2‐aminobezamide (1 mmol),
30 min at 25 °C.
byields after purification.
c1 h.
TABLE 4 One‐pot synthesis of tri substituted imidazoles under solvent‐free condition at 100 °C.
Entry
R1
Product
Time (min)
Yield (%)b
[M.p (M.p)c]
1
2
3
4
5
6
7
8
9
C6H5
1a
1b
1c
1d
1e
1f
35
60
97
98
97
97
96
98
88
98
98
[273–274 (274–276)[32]
[258–259 (260–261)[32]
[249–250 (254–256)[32]
[231–233 (234–236)[32]
]
]
]
]
4‐ClC6H4
4‐BrC6H4
60
4‐NO2C6H4
4‐OHC6H4
3‐NO2C6H4
4‐FC6H4
65
20
[264–265(268–270)[32]
[315–318 (311–315)[33]
]
110
70
]
1 g
1 h
1i
[247–248 (238)[24]
]
[228–229 (228–231)[34]
[212–214(213–216)[34]
4‐OCH3C6H4
3,4‐(OCH3)2C6H3
70
]
120
aReaction conditions: aldehyde (1 mmol), benzyl (1 mmol), ammonium acetate (4.5 mmol) catalyst (0.01 g) and solvent‐free.
byields after purification.
cM.p found (°C) in the literatures.

HAJJAMI ET AL.
7 of 9
3.1.7 | Energy dispersive X‐ ray spectroscopy
3.2 | Catalytic studies
(EDS)
The prepared catalyst has been used for the preparation of tri/
tetra substituted imidazoles and 2,3‐dihydroquinazolin‐4
(1H)‐ones. Thus, after screening different amounts of the
synthesized catalyst (Table 2, 3). the results show that
0.01 g of the catalyst was the best amounts for the synthesis
Based on energy dispersive X‐ ray spectroscopy(EDS) for the
catalyst, the amounts of Cu (I) in the complex of SBA‐ 15
was 6.96 mmol/g. Sequencely for the C, N, O and Si was
17.87, 4.59, 38.97 and 31.62 mmol/g (Figure 6).
TABLE 5 One‐pot synthesis of tetra substituted imidazoles under solvent‐free condition at 100 °C.
Entry
R1
R2
Product
Time (min)
Yield (%)b
[M.p (M.p)c]
1
2
3
4
5
6
7
8
4‐ClC6H4
4‐ClC6H4
C6H5CH2
C6H5
1j
180
75
94
95
96
95
98
98
98
98
[191–193(188–190)[35]
[162–165(162–165)[36]
[183–184(179–183)[29]
[182–184(181–182)[31]
[147–148(146–148)[35]
[242–244(243–246)[37]
[157–158(161–163)[29]
[228–229(229–231)[29]
]
]
]
]
]
]
]
]
4‐ClC6H4
1 k
1 l
1 m
1n
1o
1p
1q
4‐BrC6H4
120
35
4‐OHC6H4
4‐ClC6H4
C6H5
C6H5
105
100
180
30
3‐NO2C6H4
3,4‐(OCH3)2C6H3
3‐OHC6H4
C6H5
C6H5CH2
C6H5CH2
aReaction conditions: aldehyde (1 mmol), benzyl (1 mmol), ammonium acetate (4.5 mmol), amine(1 mmol), catalyst (0.01 g) and solvent‐free.
byields after purification.
cM.p found (°C) in the literatures.
TABLE 6 Synthesis of 2,3‐dihydroquinazolin‐4(1H)‐one derivativesa
Entry
R
Product
Time (min)
Yield (%)b
[M.p (M.p)c]
1
2
C6H5
2a
2b
2c
2d
2e
2f
50
60
80
96
94
98
97
86
98
97
94
95
[216–218 (219–221)[38]
[201–202 (198–200)[38]
[198–200 (197–199)[19]
[211–212 (213–214)[39]
[210–213 (213–216)[29]
[198–200 (192–193)[40]
[185–187 (189–192)[19]
]
]
]
]
]
]
]
4‐ClC6H4
3
4‐BrC6H4
65
4
4‐NO2C6H4
3‐NO2C6H4
4‐FC6H4
105
30
5
6
40
7
4‐OCH3C6H4
3,4‐(OCH3)2C6H3
4‐CH3C6H4
4‐OCH2CH3C6H4
2 g
2 h
2i
65
8
105
90
[211–213(209–211)[38]
[227–229(234–236)[38]
[163–166(167–168)[40]
]
9
]
]
10
2j
75
aReaction conditions: aldehyde (1 mmol), 2‐aminobezamide (1 mmol), CH2Cl2 (2 mL), catalyst (0.03 g) and 25 °C.
byields after purification.
cM.p found (°C) in the literatures

8 of 9
HAJJAMI ET AL.
the catalyst reusability and recycling was investigated. The
catalyst is insoluble in CH2Cl2 and therefore when the reac-
tion was complete, could be recycled of the reaction mixture
by simple filtration and washed with CH2Cl2. The recovered
catalyst was dried and reused for subsequent runs and could
be reused five times without any significant loss of its activity
(Figure 7). Also in order to determine any leaching of copper
(I) in the reaction mixture and to show that Cu (I)‐1,3‐
dimethylbarbituric acid modified SBA‐15 is a heterogeneous
catalyst, we performed hot filtration test in the reaction of 3‐
nitro benzaldehyde with 2‐aminobezamide in the synthesis of
2,3‐dihydroquinazolin‐4(1H)‐ones. In this study we found
the yield of product in the half time of the reaction was
91%. Then the reaction was repeated and in half time of the
reaction, the catalyst separated and allowed the filtrate to
react further. The yield of reaction in this stage was 90% that
confirmed the leaching of copper (I) has not been significant.
FIGURE 7 The recycling experiment of catalyst for synthesis of
2‐(3‐nitro phenyl)‐2,3‐dihydroquinazolin‐4(1H)‐one at room
temperature in 30 min
of tri substituted imidazoles (Table 2, entry 2) and 0.03 g of
the catalyst was the best amounts for the synthesis of 2,3‐
dihydroquinazolin‐4(1H)‐ones (Table 3, entry 2).
To achieve suitable solvent for the synthesis of 2,3‐
dihydroquinazolin‐4(1H)‐ones various solvents have been
investigated in the reaction of 3‐nitro benzaldehyde,
2‐aminobezamide and0.03 g catalyst as a model reaction. Reac-
tions in various solvents showed that the best conditions were
CH2Cl2 at 25 °C (Table 3, entry 7). At the same time the results
of optimize the solvent and temperature for the synthesis of
substituted imidazoles showed that the best conditions were
solvent‐free at 100 °C (Table 2, entry 8 and Table 2, entry 11).
Also inTable 2 the results ofoptimization of ammonium acetate
for the synthesis of substituted imidazoles have been investi-
gated. The best results were obtained with molar ratio of 1:
4.5 for aldehyde: ammonium acetate (Table 2, entry 15).
After the reaction is optimized and the best conditions
were chosen, several substituted of benzaldehydes reacted
with benzil and ammonium acetate/ammonium acetate and
primary amines for the synthesis of substituted imidazoles
in the presence of heterogeneous acid catalysts to give the
corresponding tri/tetra substituted imidazoles in good yields.
The results of synthesis of substituted imidazoles tabulated in
(Table 4, 5). Also several substituted aromatic aldehydes
reacted with 2‐aminobezamide in the presence of Cu(I)‐1,3‐
dimethylbarbituric acid modified SBA‐15 catalyst provided
the corresponding 2,3‐dihydroquinazolin‐4(1H)‐ones in
excellent yields (Table 6). One of the most important advan-
tages of this catalyst is the large surface areas of SBA‐15 that
makes this material very attractive as support for
immobilizing complex of copper(I) as Lewis acid catalyst
for synthesis of 2,3‐dihydroquinazolin‐4(1H)‐ones and tri/
tetra substituted imidazoles.
4 | CONCLUSION
In summary, we have displayed a simple method for the
organic synthesis using the Cu (I)‐1,3‐dimethylbarbituric
acid modified SBA‐15 as a heterogeneous catalyst. The cata-
lyst showed high catalytic activity in the synthesis of tri/tetra
substituted imidazoles and 2,3‐dihydroquinazolin‐4(1H)‐
ones. Some notable features of this work are short reaction
times, high yield, purity yields, simple and eco‐friendly, easy
work‐up, recyclability and reusability of the catalyst and no
significant leaching of Cu.
ACKNOWLEDGEMENTS
The authors acknowledge Ilam University, Ilam, Iran for
financial support of this work.
REFERENCES
[1] Z. D. Huang, W. Bensch, L. Kienle, S. Fuentes, G. Alonso, C.
Ornelas, Catal. Lett. 2008, 122, 57.
[2] Z. Huang, W. Bensch, W. Sigle, P. A. van Aken, L. Kienle, T.
Vitoya, H. Modrow, T. Ressler, J. Mater. Sci. 2008b, 43, 244.
[3] L. Chmielarz, P. Kustrowski, M. Drozdek, M. Rutkowska, R.
Dziembaj, M. Michalik, P. Cool, E. F. Vansant, J. Porous Mater.
2011, 18, 483.
[4] M. H. Mallah, M. Ghannadi Maragheh, A. Badiei, R. Habibzadeh
Sbo, J. Radioanal. Nucl. Chem. 2010, 283, 597.
[5] B. Yan, L. L. Kong, Nanoscale Res. Lett. 2010, 5, 1195.
[6] E. Kim, H. E. Kim, S. J. Lee, S. S. Lee, M. L. Seo, J. H. Jung,
Chem. Commun. 2008, 3921.
3.3 | Reusability and recycling of the catalyst
[7] Y. Li, B. Yan, J. L. Liu, Nanoscale Res. Lett. 2010, 5, 797.
In a model reaction and in the reaction between 3‐nitro benz-
aldehyde, 2‐aminobezamide, CH2Cl2, at 25 °C for 30 min,
[8] H. Veisi, A. Sedrpoushan, A. R. Faraji, M. Heydari, S. Hemmati,
B. Fatahi, RSC Adv. 2015, 5, 68523.

HAJJAMI ET AL.
9 of 9
[9] D. Dhar, I. Beadham, S. Chandrasekaran, Indian Acad. Sci. 2003,
[27] Z. Huang, W. Bensch, W. Sigle, P. A. van Aken, L. Kienle, T.
115,365.
Vitoya, H. Modrow, T. Ressler, J. Mater. Sci. 2008c, 43, 244.
[10] X. Li, X. Wu, J. M. Kim, S. S. Kim, M. Jin, D. Li, J. Am. Soc. Mass
Spectrom. 2009, 20, 2167.
[28] H. Chen, Y. Wang, Ceram. Int. 2002, 28, 541.
[29] M. Hajjami, A. Ghorbani‐Choghamarani, Z. Yousofvand, M.
Norouzi, J. Chem. Sci. 2015, 127, 1221.
[11] X. Lian, B. Yan, New J. Chem. 2013, 37, 1.
[12] D. Brunel, A. Chauvel, F. Fatula, F. Direnzo, Stud. Surf. Sci. Catal.
1995, 97, 173.
[30] M. Hajjami, Z. Yousofvand, Catal. Lett. 2015, 145, 1733.
[31] A. Ghorbani‐Choghamarani, F. Ghorbani, Z. Yousofvand, G.
Azadi, J. Porous Mater. 2015, 22, 665.
[13] Q. Wang, D. F. Shantz, J. Solid State Chem. 2008, 181, 1659.
[14] J. F. Diaz, K. J. Balkus, F. Bedioui, V. Kurs Hev, L. Keyvan, Chem.
Mater. 1997, 96, 1.
[32] A. Teimouri, A. Najafi Chermahini, J. Mol. Catal. A: Chem. 2011,
346, 39.
[15] K. Niknam, N. Jafarpour, E. Niknam, Chin. Chem. Lett. 2011a, 22, 69.
[16] F. Wang, P. Zhao, C. Xi, Tetrahedron Lett. 2011, 52, 231.
[33] M. Wang, J. Gao, Z. Song, Prep. Biochem. Biotechnol. 2010, 40, 347.
[34] J. Safari, S. Dehghan Khalili, S. Hossein Banitaba, Synth.
Commun. 2011, 41, 2359.
[17] P. Salehi, M. Dabiri, M. A. Zolfigol, M. Baghbanzadeh, Tetrahe-
dron Lett. 2005, 46, 7051.
[35] A. Davoodnia, M. M. Heravi, Z. Safavi‐Rad, N. Tavakoli‐Hoseini,
Synth. Commun. 2010, 40, 2588.
[18] B. V. Subba Reddy, A. Venkateswarlu, C. Madan, A. Vinu, Tetra-
hedron Lett. 2011, 52, 1891.
[36] A. Emrani, A. Davoodnia, N. Tavakoli‐Hoseini, Bull. Korean
Chem. Soc. 2011, 32, 2385.
[19] A. Ghorbani‐Choghamarani, P. Zamani, J. Iran, Chem. Soc. 2012,
9, 607.
[37] J. Safari, S. Gandomi‐Ravandi, Z. Akbari, J. Adv. Res. 2013, 4, 509.
[38] S. B. Saffar‐Teluri, Monatsh. Chem. 2010, 141, 1113.
[20] M. Hajjami, B. Tahmasbi, RSC Adv. 2015, 5, 59194.
[21] M. R. Mohammadizadeh, A. Hasaninejad, M. Bahramzadeh,
[39] J. Chen, W. Su, H. Wu, M. Liub, C. Jin, Green Chem. 2007, 9, 972.
Synth. Commun. 2009, 39, 3232.
[40] A. Ghorbani‐Choghamarani, M. Norouzi, J. Mol. Catal. A: Chem.
2014, 395, 172.
[22] C. Mukhopadhyay, P. K. Tapaswi, Green Chem. Lett. Rev. 2012, 5, 109.
[23] S. Samai, G. Chandra Nandi, P. Singh, M. S. Singh, Tetrahedron
2009, 65, 10155.
How to cite this article: Hajjami M, Ghorbani F,
Yousofvand Z. Copper(I) complex of 1,3‐
DimethylBarbituric acid modified SBA‐15 and its
catalytic role for the synthesis of 2,3‐
Dihydroquinazolin‐4(1H)‐ones and Imidazoles. Appl
Organometal Chem. 2017:e3843. https://doi.org/
10.1002/aoc.3843
[24] S. V. Bhosale, M. B. Kalyankar, S. V. Nalage, D. S. Bhosale, S. L.
Pandhare, T. V. Kotbagi, S. B. Umbarkar, M. K. Dongare, Synth.
Commun. 2011, 41, 762.
[25] K. Niknam, A. Deris, F. Naeimi, F. Majleci, Tetrahedron Lett.
2011b, 52, 4642.
[26] A. R. Karimi, Z. Alimohammadi, M. M. Amini, Mol. Diversity
2010, 14, 635.