Aluminium nitrate-catalyzed one-pot synthesis of 4(3h)-quinazolinones by a three-component coupling of anthranilic acid, amines, and ortho esters

Article abstract of DOI:10.1080/00397910903576636

The one-pot synthesis of quinazolinone derivatives from the reaction of anthranilic acid, amines, and ortho esters in the presence of aluminium nitrate has been carried out. The reaction occurred in a few minutes at room temperature under solvent-free con

Full text of DOI:10.1080/00397910903576636

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Aluminium Nitrate–Catalyzed One-
Pot Synthesis of 4(3H)-Quinazolinones
by a Three-Component Coupling of
Anthranilic Acid, Amines, and Ortho
Esters
Min Wang a , Zhiguo Song b & Tingting Zhang a
a College of Chemistry and Chemical Engineering, Bohai University ,
Jinzhou, Liaoning, China
b Center for Science and Technology Experiment, Bohai University ,
Jinzhou, Liaoning, China
Published online: 13 Jan 2011.
To cite this article: Min Wang , Zhiguo Song & Tingting Zhang (2011) Aluminium Nitrate–Catalyzed
One-Pot Synthesis of 4(3H)-Quinazolinones by a Three-Component Coupling of Anthranilic
Acid, Amines, and Ortho Esters, Synthetic Communications: An International Journal for Rapid
Communication of Synthetic Organic Chemistry, 41:3, 385-391, DOI: 10.1080/00397910903576636
To link to this article: http://dx.doi.org/10.1080/00397910903576636
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Synthetic Communications1, 41: 385–391, 2011
Copyright # Taylor & Francis Group, LLC
ISSN: 0039-7911 print=1532-2432 online
DOI: 10.1080/00397910903576636
ALUMINIUM NITRATE–CATALYZED ONE-POT
SYNTHESIS OF 4(3H)-QUINAZOLINONES BY A
THREE-COMPONENT COUPLING OF ANTHRANILIC
ACID, AMINES, AND ORTHO ESTERS
Min Wang,1 Zhiguo Song,2 and Tingting Zhang1
1College of Chemistry and Chemical Engineering, Bohai University, Jinzhou,
Liaoning, China
2Center for Science and Technology Experiment, Bohai University, Jinzhou,
Liaoning, China
The one-pot synthesis of quinazolinone derivatives from the reaction of anthranilic acid,
amines, and ortho esters in the presence of aluminium nitrate has been carried out. The
reaction occurred in a few minutes at room temperature under solvent-free conditions and
with excellent yield.
Keywords: Aluminium nitrate; multicomponent reactions; one-pot synthesis; 4(3H)-quinazolinones
INTRODUCTION
One of the most frequently encountered heterocycles in medicinal chemistry is
4(3H)-quinazolinone, which exhibits interesting pharmacological activities including
antimalarial, antitumor, anticonvulsant, anti-inflammatory, fungicidal, antimicrobial,
and calcilytic activities.[1–7] In addition, 4(3H)-quinazolinones are present in several
bioactive natural products.[8,9] Among this class of molecules, 3-substituted-4(3H)-
quinazolinones are well known because they are present in a large family of products
with broad biological activities. For these reasons, their synthesis has received
considerable attention. Several conventional preparation methods required refluxed
temperature and long reaction time (3 days).[10–12]
Recently, new developments for the synthesis of 3-substituted-4(3H)-
quinazolinones by a three-component, one-pot condensation of anthranilic acid,
amines, and ortho esters in the presence of various catalysts such as NaHSO4
or Amberlyst-15,[13] Yb(III)-resin,[14] Yb(OTf)3,[15] Bi(TFA)3-[nbp]FeCl4 ionic
liquid,[16] La(NO3)3 ꢀ 6H2O or p-toluenesulfonic acid,[17] Keggin-type heteropolyacid
under microwave irradiation,[18] SnCl4 ꢀ 4H2O,[19] and SiO2-FeCl3
have been
reported. However, some of these methods are associated with certain drawbacks
such as expensive catalyst, high temperatures (60–80 ꢁC), and long reaction times
20]
Received August 27, 2009.
Address correspondence to Min Wang, College of Chemistry and Chemical Engineering, Bohai
University, Jinzhou, Liaoning, China. E-mail: minwangszg@yahoo.com.cn
385

386
M. WANG, Z. SONG, AND T. ZHANG
Scheme 1. Synthesis of 4(3H)-quinazolinones using Al(NO3)3 ꢀ 9H2O.
(20 h). In addition, anilines having strong electron-withdrawing substitutes (e.g., Cl
and NO2), generally gave no products at room temperature in previous reports.
Therefore, it is desirable to develop green and efficient methods for the synthesis
of 4(3H)-quinazolinones.
During the course of our studies on the development of green catalytic
processes, we found that aluminium nitrate [Al(NO3)3 ꢀ 9H2O], an inexpensive and
commercially available catalyst, can efficiently catalyze a one-pot synthesis of
3-substituted-4(3H)-quinazolinones via a three-component condensation of anthra-
nilic acid, amines, and ortho esters (Scheme 1). The reaction was carried out at room
temperature under solvent-free conditions. The products 4 were formed within a few
minutes in excellent yields.
RESULTS AND DISCUSSION
In a model reaction of anthranilic acid with aniline and triethyl orthoformate,
a controlled experiment in the absence of catalyst was carried out first at room
temperature; the result showed that little product (yield 5%) was produced after
1 h. However, quantitative yield (yield 99%) of the product was obtained after
40 min when 2 mol% Al(NO3)3 ꢀ 9H2O was added (Table 1, 4a).
Encouraged by this result, we investigated the scope and limitations of this
reaction using anthranilic acid 1, different substituted aryl amines or alkyl amine
2, and triethyl or trimethyl orthoformate 3 at room temperature in the presence of
Al(NO3)3 ꢀ 9H2O; the results were shown in Table 1. Most reactions are completed
within 1 h, and quantitative yields were obtained. Both triethyl orthoformate and
trimethyl orthoformate were utilized for the preparation of 3-substituted-4(3H)-
quinazolinones. The yields of products from trimethyl orthoformate were less than
those from triethyl orthoformate. Therefore, trimethyl orthoformate proved to be
less active than triethyl orthoformate in this reaction. Except for 4j, aryl amines
containing electron-donating as well as electron-withdrawing groups underwent
the conversion smoothly. o-Nitroaniline gave lesser yields, possibly because of the
steric reason and the decreased electron density of the aromatic system (4j). Besides
aryl amines, alkyl amine, such as benzyl amine were also investigated, and moderate
yield was provided when using triethyl orthoformate (4n).
A probable mechanism for this reaction has also been postulated as shown in
Scheme 2. The first step in this reaction involves the Al(NO3)3 ꢀ 9H2O-catalyzed for-
mation of imidic ester 5, which was stabilized by Al3þ. The imidic ester 5 may be very
prone to react with an aryl amine 3, thus leading to the amidine intermediate 6.
Then, amidine intermediate 6 activated by Al3þ cyclized to form the quinazolinone
4. A similar mechanism had also been described by Wang et al.[15]

ALUMINIUM NITRATE AS AN EFFICIENT CATALYST
387
Table 1. Al(NO3)3 ꢀ 9H2O-catalyzed synthesis of 3-substituted 4(3H)-quinazolinones 4a–na
Product 4
R1
R
Time (min)
Isolated yield (%)
4a
Ph
Et
40
150
45
35
120
240
20
47
30
80
23
37
3
99
90
99
81
99
73
96
99
99
91
92
72
83
75
83
96
94
93
45
36
84
81
95
55
70
49
53
5
Me
Et
4b
4c
4d
4e
4f
2-MeC6H4
3-MeC6H4
4-MeC6H4
2-MeOC6H4
4-MeOC6H4
2-ClC6H4
Me
Et
Me
Et
Me
Et
Me
Et
Me
Et
4g
4h
4i
Me
Et
13
10
14
10
8
4-ClC6H4
Me
Et
4-BrC6H4
Me
Et
4j
2-NO2C6H4
3-NO2C6H4
4-NO2C6H4
4-COOHC6H4
PhCH2
240
17
8
Me
Et
4k
4l
Me
Et
3
2
Me
Et
5
4m
4n
1
Me
Et
7
1
36
Me
aThe structures of the products were determined from spectral and analytical data (IR, 1H
NMR, and elemental analysis).
Scheme 2. Proposed mechanism.

388
M. WANG, Z. SONG, AND T. ZHANG
CONCLUSION
In conclusion, we have demonstrated an efficient and environmentally friendly
approach for the synthesis of 4(3H)-quinazolinones via a three-component, one-pot
condensation of anthranilic acid, amines, and ortho esters using Al(NO3)3 ꢀ 9H2O as
catalyst. Execellent yields, reduced reaction time, mild reaction condition, easy
workup, and inexpensive and commercially available catalyst make this approach
as an interesting alternative to the existing methods.
EXPERIMENTAL
Apparatus
Melting points were determined using a RY-1 micromelting-point apparatus
and are uncorrected. Infrared (IR) spectra were recorded on a Scimitar 2000 series
1
Fourier transform (FT) Varian instrument. H NMR spectra were recorded on a
Bruker ARX-500 spectrometer in dimethylsulfoxide (DMSO-d6) using tetramethylsi-
lane (TMS) as an internal standard. Elemental analyses were carried out on an EA
2400II elemental analyzer (Perkin-Elmer).
General Procedure
A mixture of anthranilic acid 1 (10 mmol), an amine 2 (12 mmol), an orthoester
3 (12 mmol), and Al(NO3)3 ꢀ 9H2O (0.2 mmol) was stirred at room temperature for
an appropriate time (Table 1). The reaction was monitored by thin-layer chromato-
graphy (TLC). After completion, the solid obtained was crystallized in ethanol. The
1
pure products were identified by mp, IR, H NMR, and elemental analysis.
Spectral Data for Compounds 4a–n
Compound 4a. Pale yellow solid; mp 139–141 ꢁC (lit. 139–140 ꢁC[15]); IR
;
(KBr): 1689, 1598, 1462 cmꢂ1 1H NMR (500 MHz, DMSO-d6): d 8.32 (s, 1H),
8.19 (d, J ¼ 7.6 Hz, 1H), 7.78–7.72 (m, 2H), 7.49 (t, J ¼ 7.5 Hz, 1H), 7.35–7.27
(m, 5H); Anal. calcd. for C14H10ON2: C, 75.66; H, 4.54; O, 7.20%. Found: C,
75.62; H, 4.55; O, 7.21%.
Compound 4b. White solid; mp 158–159 ꢁC; IR (KBr): 1687, 1595, 1489 cmꢂ1
;
1H NMR (500 MHz, DMSO-d6): d 8.56 (s, 1H), 8.31 (d, J ¼ 7.2 Hz, 1H), 7.75–7.52 (m,
2H), 7.24–7.07 (m, 5H), 2.31 (s, 3H). Anal. calcd. for C15H12ON2: C, 76.26; H, 5.12; O,
6.77%. Found: C, 76.32; H, 5.11; O, 6.76%.
Compound 4c. Yellow solid; mp 142–143 ꢁC (lit. 136–137 ꢁC[15]); IR (KBr):
;
1690, 1595, 1457 cmꢂ1 1H NMR (500 MHz, DMSO-d6): d 8.39 (s, 1H), 8.14
(d, J ¼ 7.5 Hz, 1H), 7.73–7.65 (m, 2H), 7.42 (t, J ¼ 7.3 Hz, 1H), 7.34–7.21 (m, 4H),
2.26 (s, 3H). Anal. calcd. for C15H12ON2: C, 76.26; H, 5.12; O, 6.77%. Found: C,
76.29; H, 5.11; O, 6.78%.
Compound 4d. White solid; mp 145–148 ꢁC (lit. 146–147 ꢁC[15]); IR (KBr):
;
1681, 1595, 1456 cmꢂ1 1H NMR (500 MHz, DMSO-d6): d 8.49 (s, 1H), 8.07

ALUMINIUM NITRATE AS AN EFFICIENT CATALYST
389
(d, J ¼ 7.6 Hz, 1H), 7.71–7.69 (m, 2H), 7.42 (t, J ¼ 7.5 Hz, 1H), 7.31 (d, J ¼ 7.2 Hz,
2H), 7.15 (d, J ¼ 7.3 Hz, 2H), 3.16 (s, 3H). Anal. calcd. for C15H12ON2: C, 76.26;
H, 5.12; O, 6.77%. Found: C, 76.22; H, 5.13; O, 6.77%.
Compound 4e. White solid; mp 150–153 ꢁC; IR (KBr): 1681, 1595, 1456 cmꢂ1
;
1H NMR (500 MHz, DMSO-d6): d 8.36 (s, 1H), 8.21 (d, J ¼ 7.7 Hz, 1H), 7.45
(d, J ¼ 6.8 Hz, 1H), 7.25 (t, J ¼ 7.0 Hz, 1H), 7.08–7.03 (m, 2H), 6.94 (t, J ¼ 7.1 Hz,
1H), 6.78 (d, J ¼ 8.2 Hz, 1H), 6.54 (t, J ¼ 7.3 Hz, 1H), 3.85 (s, 3H). Anal. calcd. for
C15H12O2N2: C, 71.42; H, 4.80; O, 12.68%. Found: C, 71.47; H, 4.79; O, 12.66%.
Compound 4f. White solid; mp 132–134 ꢁC; IR (KBr): 1716, 1591, 1454 cmꢂ1
;
1H NMR (500 MHz, DMSO-d6): d 8.54 (s, 1H), 8.05 (d, J ¼ 7.5 Hz, 1H), 7.54–7.51 (m,
2H), 7.16 (t, J ¼ 7.5 Hz, 1H), 6.97 (dd, J ¼ 8.5, 9.5 Hz, 4H), 3.76 (s, 3H). Anal. calcd.
for C15H12O2N2: C, 71.42; H, 4.80; O, 12.68%. Found: C, 71.36; H, 4.81; O, 12.67%.
Compound 4g. Yellow solid; mp 118–120 ꢁC; IR (KBr): 1667, 1601,
1
1414 cmꢂ1; H NMR (500 MHz, DMSO-d6): d 8.57 (s, 1H), 8.02 (d, J ¼ 7.7 Hz,
1H), 7.73–7.71 (m, 2H), 7.61 (t, J ¼ 7.6 Hz, 1H), 7.25–7.16 (m, 2H), 6.76
(d, J ¼ 8.1 Hz, 1H), 6.53 (t, J ¼ 7.2 Hz, 1H). Anal. calcd. for C14H9ON2Cl: C,
65.51; H, 3.53; O, 6.23; N, 10.91%. Found: C, 65.45; H, 3.52; O, 6.23; N, 10.93%.
Compound 4h. Pale yellow solid; mp 124–125 ꢁC; IR (KBr): 1672, 1616,
;
1484 cmꢂ1 1H NMR (500 MHz, DMSO-d6): d 8.52 (s, 1H), 7.71–7.69 (m, 2H),
7.24–7.20 (m, 2H), 6.75 (d, J ¼ 7.5 Hz, 2H), 6.52 (d, J ¼ 7.2 Hz, 2H). Anal. calcd.
for C14H9ON2Cl: C, 65.51; H, 3.53; O, 6.23; N, 10.91%. Found: C, 65.57; H, 3.53;
O, 6.22; N, 10.90%.
Compound 4i. White solid; mp 149–151 ꢁC; IR (KBr): 1712, 1587, 1443 cmꢂ1
;
1H NMR (500 MHz, DMSO-d6): d 8.55 (s, 1H), 8.01 (d, J ¼ 7.7 Hz, 1H), 7.60
(t, J ¼ 7.5 Hz, 1H), 7.46–7.44 (m, 4H), 7.19 (d, J ¼ 7.5 Hz, 2H). Anal. calcd. for
C14H9ON2Br: C, 55.84; H, 3.01; O, 5.31; N, 9.30%. Found: C, 55.81; H, 3.00; O,
5.32; N, 9.31%.
Compound 4j. Yellow solid; mp 148–150 ꢁC (lit. 156–158 ꢁC[15]); IR (KBr):
;
1697, 1602, 1476 cmꢂ1 1H NMR (500 MHz, DMSO-d6): d 8.52 (s, 1H), 8.19
(d, J ¼ 7.7 Hz, 1H), 7.71–7.66 (m, 2H), 7.53 (t, J ¼ 7.6 Hz, 1H), 7.25–7.19 (m, 4H).
Anal. calcd. for C14H9O3N3: C, 62.92; H, 3.39; O, 17.96%. Found: C, 62.96; H,
3.40; O, 17.95%.
Compound 4k. Yellow solid; mp 150–153 ꢁC (lit. 154–156 ꢁC[15]); IR (KBr):
;
1711, 1596, 1470 cmꢂ1 1H NMR (500 MHz, DMSO-d6): d 8.51 (s, 1H), 8.10
(d, J ¼ 7.6 Hz, 1H), 7.67–7.62 (m, 2H), 7.45 (t, J ¼ 7.4 Hz, 1H), 7.24–7.13 (m, 4H).
Anal. calcd. for C14H9O3N3: C, 62.92; H, 3.39; O, 17.96%. Found: C, 62.88; H,
3.40; O, 17.98%.
Compound 4l. Yellow solid; mp 166–168 ꢁC (lit. 165–166 ꢁC[15]); IR (KBr):
;
1701, 1623, 1477 cmꢂ1 1H NMR (500 MHz, DMSO-d6): d 8.51 (s, 1H), 8.12
(d, J ¼ 7.6 Hz, 1H), 7.82 (m, 2H), 7.53 (t, J ¼ 7.4 Hz, 1H), 6.98 (d, J ¼ 8.5 Hz, 2H),
6.73 (d, J ¼ 8.6 Hz, 2H). Anal. calcd. for C14H9O3N3: C, 62.92; H, 3.39; O,
17.96%. Found: C, 62.95; H, 3.38; O, 17.97%.

390
M. WANG, Z. SONG, AND T. ZHANG
Compound 4m. White solid; mp 240–242 ꢁC; IR (KBr): 1700, 1592, 1483cmꢂ1
;
1H NMR (500 MHz, DMSO-d6): d 10.49 (s, 1H), 8.35 (s, 1H), 7.92–7.88 (m, 3H), 7.71
(t, J ¼ 8.5 Hz, 2H), 7.63 (d, J ¼ 5.5 Hz, 1H), 7.31 (d, J ¼ 8.5 Hz, 1H), 6.56 (d, J ¼ 5.5 Hz,
1H). Anal. calcd. for C15H10O3N2: C, 67.67; H, 3.79; O, 18.03%. Found: C, 67.71; H,
3.78; O, 18.02%.
Compound 4n. White solid; mp 154–155 ꢁC; IR (KBr): 1677, 1620, 1459 cmꢂ1
;
1H NMR (500 MHz, DMSO-d6): d 8.52 (s, 1H), 8.00 (d, J ¼ 7.5 Hz, 1H), 7.54–7.47
(m, 2H), 7.41–7.37 (m, 4H), 7.32 (t, J ¼ 6.8 Hz, 1H), 7.14 (t, J ¼ 7.0 Hz, 1H), 4.61
(s, 2H). Anal. calcd. for C15H12ON2: C, 76.26; H, 5.12; O, 6.77%. Found: C, 76.21;
H, 5.13; O, 6.78%.
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