DABCO containing acidic poly(ionic liquid): An efficient catalyst for the one-pot preparation of 2,3-dihydroquinazoline-4(1H)-ones

Article abstract of DOI:10.4314/bcse.v31i3.17

1,4-Diazabicyclo[2.2.2]octane (DABCO) containing acidic poly(ionic liquid) (DAIL) has been prepared via condensation of 1,4-dichloro butane and DABCO, as an efficient acidic catalyst and has been applied in the one-pot preparation of 2,3-dihydroquinazolin

Full text of DOI:10.4314/bcse.v31i3.17

Bull. Chem. Soc. Ethiop. 2017, 31(3), 535-544.
 2017 Chemical Society of Ethiopia and The Authors
DOI: http://dx.doi.org/10.4314/bcse.v31i3.17
ISSN 1011-3924
Printed in Ethiopia
DABCO CONTAINING ACIDIC POLY(IONIC LIQUID): AN EFFICIENT CATALYST
FOR THE ONE-POT PREPARATION OF 2,3-DIHYDROQUINAZOLINE-4(1H)-ONES
Mohammad Kazem Mohammadi1*, Seyyed Jafar Saghanezhad2 and Nima Razzaghi-asl3
1Department of Chemistry, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran
2ACECR-Production Technology Research Institute, Ahvaz, Iran
3Department of Medicinal Chemistry, School of Pharmacy, Ardabil University of Medical
Sciences, Ardabil, Iran
(Received November 24, 2017; Revised December 19, 2017; Accepted December 21, 2017)
ABSTRACT. 1,4-Diazabicyclo[2.2.2]octane (DABCO) containing acidic poly(ionic liquid) (DAIL) has been
prepared via condensation of 1,4-dichloro butane and DABCO, as an efficient acidic catalyst and has been applied
in the one-pot preparation of 2,3-dihydroquinazolin-4(1H)-one derivatives. This catalyst has been characterized by
FT-IR and TGA. According to the obtained results including time, yield and recyclability, DAIL could be
considered as an efficient catalyst for organic transformations.
KEY WORDS: Poly(ionic liquid), Solvent-free, 2,3-Dihydroquinazolin-4(1H)-ones, DABCO, Multi-component
reaction
INTRODUCTION
According to the simplicity, high yield of the products and one-pot synthesis, multi-component
reactions (MCRs) have been greatly acknowledged. Due to the formation of multiple bonds in a
continuous manner without the need for separation of intermediate adducts MCRs are gaining
more attention lately [1-3]. Applications of homogeneous or heterogeneous catalysts or
performing reaction in unconventional solvents are new strategies for obtaining desired products
[4, 5].
Solvent-free organic reactions have been devised as an alternative tool for organic synthesis
particularly from the viewpoint of green chemistry. Reduced pollution, lower costs, and
simplicity in process and work-up are some advantages of solvent-free synthesis [6, 7].
Poly(ionic liquid)s (PILs) are considered as new materials with numerous potential
applications in many fields such as energy and environment, analytical chemistry, materials
science, biotechnology, catalysts or surface science [8, 9]. The superiority of PILs over ionic
liquids (ILs) are the enhanced mechanical stability, improved process ability, durability, and
spatial controllability. Two basic strategies have been utilized for PILs synthesis, 1) direct
polymerization of IL monomers and 2) post-modification of existing polymers [10]. Recently
the scientists have focused on the preparation of nano-sized and nano-structured PILs [11]. Due
to the diverse biological activities [12], synthesis of quinazolinone derivatives is a demanding
task. Numerous synthetic methods have been developed for the synthesis of quinazolinone
derivatives using silica sulfuric acid [13], gallium(III) triflate [12], MCM-41-SO3H [15], 1-
butyl-3-methylimidazolium tetrafluoroborate [16], molecular iodine [17], β-cyclodextrin [18],
and metal–MWCNTs nanocomposites [19, 20]. Most of these methods suffer from one or more
of these disadvantages, such as the use of hazardous organic solvents, low yields, strongly acidic
conditions, expensive moisture-sensitive catalysts, and tedious work-up procedure [21].
Accordingly we decided to propose a greener procedure for the preparation of 2,3-
dihydroquinazolin-4(1H)-one derivatives in the presence of catalytic amounts of DAIL under
solvent-free conditions (Scheme 1).
__________
*Corresponding author. E-mail: mohammadi@iauahvaz.ac.ir
This work is licensed under the Creative Commons Attribution 4.0 International License

536
Mohammad Kazem Mohammadi et al.
CHO
O
O
R
N
O
or
H
NH2
NH4OAc
DAIL
or
O
O
NH
N
N
H
N
H
R
R
Scheme 1. Three-component rreaction of isatoic anhydride, aromatic aldehydes and ammoonium
acetate/aniline for the one-pot preparation of 2-aryl-2,3-dihydroquinazolin-44(1H)-
ones and 2,3-disub
s
s
tituted-2,3-dihydroquinazolin-4(1H)-ones.
EXPRIMENTAL
Materials and physical measu
r
r
ements
All commercially available c
h
h
emicals were purchased from Fluka and Merck companiees and
used without further purificat
ii
on. Reaction monitoring was accomplished by TLC on siliica gel
polygram SILG/UV 254 platees. The IR spectra were recorded on a BOMEM MB-Seriess 1998
FT-IR spectrophotometer usi
n
g KBr pellets for the samples and the catalyst in the rannge of
1
4000–400 cm−1. H and 13C NMR spectra were recorded in CDCl3 and DMSO-d6 on a BBruker
Advanced DPX 400 MHz spe
carried out using a LEO 1455
O analysis was conducted by
cctrometer using TMS as internal standard. The SEM analysess were
V
P Scanning Electron Microscope, operating at 1-30 KV. CCHNS-
C
General procedure for the preepparation of DABCO containing acidic poly(ionic liquid) (DAIL)
In the first step, in
a
50 mL three neck-round-bottom flask, DABCO (1,4-
diazabicyclo[2.2.2]octane) (10 mmol, 1.12 g) was dissolved in ethylene glycol (2.5 mLL) and
under nitrogen atmosphere, ,4-dichloro butane was added drop wise to the flask in 300 min.
1
1
Afterwards, the mixture was mixed for 8 hours at 110 ºC to form the polymer. The obbtained
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DABCO containing acidic poly(ionic liquid)
537
polymer was washed with dichloromethane and after drying in the oven at 60 ºC for 12 hours, a
white solid (1.8 g) was obtained.
The obtained solid was mixed with 2 equivalent of sulfuric acid drop wise in the
dichloromethane. The mixture was refluxed for 48 hours under nitrogen atmosphere and the HCl
gas was trapped in an alkaline solution. At last, DAIL was filtered and dried in the oven at 60 ºC
for 12 hours.
General procedure for the preparation of 2,3-dihydroquinazolin-4(1H)-one
A mixture of isatoic anhydride (1.0 mmol), aromatic aldehyde (1.0 mmol), and ammonium
acetate (1.5 mmol) or aniline (1.0 mmol), in the presence of DAIL (0.01 g) were thoroughly
o
mixed and heated under solvent-free conditions at 90 C. Completion of the reaction was
indicated by TLC [ethyl acetate/n-hexane (2:5)]. After completion of the reaction (as indicated
in Table 2 and Table 3) the insoluble crude product was dissolved in hot ethanol and DAIL was
removed by an external magnet. The filtrate was concentrated and the products were
recrystallized from aqueous acetone or aqueous ethanol.
RESULT AND DISSCUSSION
In the first step, the catalyst was prepared by the nucleophilic attack of DABCO onto 1,4-
dichloro butane to form the adduct. To characterize the adduct the FT-IR spectrum was
−
recorded. In the next step, the chloride anion was exchanged by HSO4 . To characterize the
catalyst, the FT-IR spectrum was recorded. Accordingly the characteristic peak of S=O between
1060 and 1228 cm-1are evident. The thermo gravimetric analysis (TGA) of the catalyst was
o
recorded too. The adsorbed water was released between 100-200 C. At about 200 ºC the
degradation of the catalyst backbone starts. The catalyst is completely decomposed at 500 oC.
After Characterization of the catalyst, it was decided to evaluate its catalytic activity in the
one-pot preparation of 2,3-dihydroquinazolin-4(1H)-one derivatives. To optimize the reaction
conditions, isatoic anhydride (1.0 mmol), aromatic aldehyde (1.0 mmol), ammonium acetate,
and DAIL were mixed in a test tube under solvent-free conditions.
Scheme 2. Preparation of the DAIL catalyst.
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Mohammad Kazem Mohammadi et al.
80
70
60
50
40
30
20
10
0
4000 3600 3200 2800 2400 2000 1600 1200 800 400
Wavenumber, cm-1
Figure 1. The FT-IR spectrum of the adduct of DABCO and 1,4-dichlorobutane.
80
70
60
50
40
30
20
10
0
4000 3600 3200 2800 2400 2000 1600 1200 800 400
Wavenumber, cm-1
Figure 2. The FTIR spectrum of DAIL.
Table 1. Optimization of reaction conditions in the presence of DAIL for the reaction of isatoic anhydride
(1.0 mmol), aromatic aldehyde (1.0 mmol) and ammonium acetate.
Entry
Ammonium acetate (mmol)
Catalyst (g)
-
T (oC)
60
60
80
90
100
Time (min)
Yielda (%)
1
2
3
4
5
1.0
1.0
1.2
1.5
1.5
200
45
45
30
25
-
0.01
0.01
0.01
0.02
15
59
95
96
aYield corresponds to isolated yield.
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DABCO containing acidic poly(ionic liquid)
539
Figure 3. The TGA of DAIL.
The best results were obtained with the molar ratio of ammonium acetate (1.5 mmol) and
0.01 g of the catalyst at 90ºC under solvent-free conditions. With the optimum reaction
conditions in hand, it was decided to evaluate the catalytic activity of DAIL, in the one-pot
preparation of 2-aryl-2, 3-dihydroquinazolin-4(1H)-ones.
After the successful preparation of 2-aryl-2,3-dihydroquinazolin-4(1H)-ones, it was
decided to broaden the scope of the catalyst by one pot preparation of 2,3-disubstituted-2,3-
dihydroquinazolin-4(1H)-ones via the reaction of isatoic anhydride (1.0 mmol),aromatic
aldehyde (1.0 mmol), aniline (1 mmol), and DAIL (0.01 g) under solvent-free conditions.The
results were summarized in Table 3.
It can be seen from Table 2 that with the presence of electron withdrawing groups in the
aromatic aldehydes, time and the yield of products increased. This is because of electron
withdrawing groups make better condition for the reaction of NH2 group with aldehydes.
The postulated mechanism has been drawn for the one-pot preparation of 2,3-disubstituted-
2,3-dihydroquinazolin-4(1H)-ones (6a-h). The reaction commences with the amidation of amine
on isatoic anhydride with the release of carbon dioxide. Subsequently, imine formation followed
by Michael addition leads to the corresponding products (Scheme 3).
With the increasing interest in green chemistry, the recyclability and reusability of the
catalyst was studied in the preparation of 2-aryl-2,3-dihydroquinazolin-4(1H)-ones. After
completion of the reaction of isatoic anhydride (1.0 mmol), aromatic aldehyde (1.0 mmol),
ammonium acetate (1.5 mmol); DAIL (0.01 g) was separated and washed with water, hot
ethanol and dried. The catalyst was used for four subsequent cycles. Small decrease in the
performance of the catalyst is observed in subsequent cycles (Figure 4).
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Mohammad Kazem Mohammadi et al.
Table 2.One pot preparation of 2-aryl-2, 3-dihydroquinazolin-4(1H)-ones in the presence of DAIL
Entry
1
Aldehyde
Product
Time (min) Yield (%)
30
95
2
3
35
93
35
92
4
5
40
45
90
88
6
7
35
45
94
87
O
CHO
NH
N
Br
H
Br
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DABCO containing acidic poly(ionic liquid)
541
Table 3. One pot preparation of 2,3-disubstituted-2,3-dihydroquinazolin-4(1H)-ones(6a-h) in the presence
of DAIL.
Entry
1
Aldehyde
Product
Time (min)
25
Yield (%)
96
2
3
4
5
30
40
35
35
94
92
87
92
O
N
N
H
NO2
O
CHO
N
6
7
40
55
88
91
N
H
Br
Br
O
N
N
H
Cl
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MMohammad Kazem Mohammadi et al.
O
H
N
H2N
H
O
N
CO2
H
O
DAIL
O
O
N
H
O
O
H
N
NH2
O
O
H
N
DAIL
N
H
N
H
O
N
H
R
DAIL
R
R
HSO4
N
= DAIL
N
n
HSO4
Scheme 3. Postulated mechaniism.
100
95
94
92
80
89
88
60
40
45
40
35
35
30
20
0
1
2
3
4
5
Time, min
Yield, %
Figure 4. The recyclability off the catalyst in the reaction of isatoic anhydride (1.0 mmmol),
aromatic aldehyde (1.0 mmol), and ammonium acetate (1.5 mmol) under solve
nnt-free
conditions.
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DABCO containing acidic poly(ionic liquid)
543
CONCLUSION
DABCO containing acidic poly(ionic liquid) (DAIL) has been utilized as an efficient acidic
catalyst in the one-pot preparation of 2,3-dihydroquinazolin-4(1H)-one derivatives. According
to the obtained results including time, yield and recyclability, DAIL could be considered as an
efficient catalyst for organic transformations.
ACKNOLEDGMENT
The authors wish to thank the Ahvaz Branch, Islamic Azad University for the financial support.
REFERENCES
1. Dömling, A.; Ugi, I. Multicomponent reactions with isocyanides. Angew. Chem. Int. Ed.
2000, 39, 3168-3210.
2. Ganem, B. Strategies for innovation in multicomponent reaction. Design. Chem. Res. 2009,
42, 463-472.
3. Singh, M.S.; Chowdhury, S. Recent developments in solvent-free multicomponent reactions: A
perfect synergy for eco-compatible organic synthesis. RSC Adv. 2012, 2, 4547-4592.
4. Climent, M.J.; Corma, A.; Iborra, S. Homogeneous and heterogeneous catalysts for
multicomponent reactions. RSC Adv. 2012, 2, 16-58.
5. Gu,Y. Multicomponent reactions in unconventional solvents: State of the art. Green Chem. 2012,
14, 2091-2128.
6. Tanaka, K.; Toda, F. Solvent-free organic synthesis. Chem. Rev. 2000, 100, 1025-1074.
7. Alikarami, M.; Amozad, M. One-pot synthesis of 2,4,5-trisubstituted imidazole derivatives
catalyzed by btppc under solvent-free conditions. Bull. Chem. Soc. Ethiop. 2017, 31, 177-
184.
8. Mecerreyes, D. Applications of ionic liquids in polymer science and technology. Prog.
Polym. Sci. 2011, 36, 1629-1648.
9. Heravi, M.M.; Ansari, P.; Saeedi, M.; Tavakoli-Hosseini, N.; Narges Karimi, N. Green and
practical synthesis of benzopyran and 3-sunstituted coumarin derivatives by Brønsted acid
ionic liquid [(CH2)4SO3HMIM][HSO4]. Bull. Chem. Soc. Ethiop. 2011, 25, 315-320.
10. Yuan, J. Antonietti M. Poly(ionic liquid)s: Polymers expanding classical property profiles.
Polymer 2011, 52, 1469-1482.
11. Yuan, J.; Mecerreyes, D.; Antonietti, M. Poly(ionic liquid)s: An update. Progr. Polym. Sci.
2013, 38, 1009-1036.
12. Erlanson, D.A.; McDowell, R.S.; Brien, T.O. Fragment-based drug discovery. J. Med.
Chem. 2004, 47, 3463-3482.
13. Dabiri, M.; Salehi, P.; Baghbanzadeh, M.; Zolfigol, M.A.; Agheb, M.; Heydari, S. Silica
sulfuric acid: An efficient reusable heterogeneous catalyst for the synthesis of 2,3-
dihydroquinazolin-4(1H)-ones in water and under solvent-free conditions. Catal. Commun.
2008, 9, 785-788.
14. Chen, J.X.; Wu, D.Z.; He, F.; Liu, M.C.; Wu, H.Y.; Ding, J.C.; Su, W.K. Gallium(III)
triflate-catalyzed one-pot selective synthesis of 2,3-dihydroquinazolin-4(1H)-ones and
quinazolin-4(3H)-ones. Tetrahedron Lett. 2008, 49, 3814-3822.
15. Rostamizadeh, S.; Amani, A.M.; Mahdavinia, G.H.; Sepehrian, H.; Ebrahimi, S. Synthesis
of some novel 2-aryl substituted 2,3-dihydroquinazoline-4(1H)-ones under solvent-free
condition via MCM-41-SO3H as a highly efficient sulfonic acid nanoreactor. Synthesis 2010,
1356–1360.
Bull. Chem. Soc. Ethiop. 2017, 31(3)

544
Mohammad Kazem Mohammadi et al.
16. Darvatkar, N.B.; Bhilare, S.V.; Deorukhkar, A.R.; Raut, D.G.; Salunkhe, M.M.
[bmim]HSO4: An efficient and reusable catalyst for one-pot three-component synthesis of
2,3-dihydro-4(1H)-quinazolinones. Green Chem. Lett. Rev. 2010, 3, 301-306.
17. Rostamizadeh, S.; Amani, A.M.; Aryan, R.; Ghaieni, H.R.; Shadjou, N. Synthesis of new 2-
aryl substituted 2,3-dihydroquinazoline-4(1H)-ones under solvent-free conditions, using
molecular iodine as a mild and efficient catalyst. Synth. Commun. 2008, 38, 3567-3576.
18. Ramesh, K.; Karnakar, K.; Satish, G.; Reddy, K.H.V.; Nageswar, Y.V.D. N-Methyl-
aniliniumtrifluoroacetate-promoted Prins reaction of α-methylene-α-tetralone dimers:
Generation of new molecular scaffolds. Tetrahedron Lett. 2012, 53, 6095-6099.
19. Safari, J.; Gandomi-Ravandi, S. Application of the ultrasound in the mild synthesis of
substituted 2,3-dihydroquinazolin-4(1H)-ones catalyzed by heterogeneous metal–MWCNTs
nanocomposites. J. Mol. Struct. 2014, 1072, 173-178.
20. Nasseri, M.A.; Sadeghzadeh, .M. Diazabicyclo[2.2.2]octane stabilized on Fe3O4 as catalysts
for synthesis of coumarin under solvent-free conditions. J. Iranian Chem. Soc. 2014, 11, 27-
33.
21. Kishore Kumar, V.; Kasi Viswanath, I.V.; Naga Raju, P.V.V.S.; Rajasekher, B.; Rama
Dasu, B. Synthesis and in-vitro studies of some new quinoline 1,3,4-thiadiazolo pyrimidine
derivatives. Bull. Chem. Soc. Ethiop. 2017, 31, 337-344.
Bull. Chem. Soc. Ethiop. 2017, 31(3)