Cellulose-SO3H: An efficient and biodegradable solid acid for the synthesis of quinazolin-4(1H)-ones

Article abstract of DOI:10.1016/j.tetlet.2011.02.030

The condensation of 2-aminobenzamide with aldehydes or ketones has been achieved using cellulosesulfonic acid under mild reaction conditions to furnish 2,3-dihydroquinazolin-4(1H)-ones in good yields with a high selectivity. The use of biodegradable solid acid catalyst, cellulosesulfonic acid makes this method quite simple, more convenient, and practical. This catalyst was also found to be very active for the synthesis of hydroxyalkylquinazolin-4-ones from cyclic enol ethers.

Full text of DOI:10.1016/j.tetlet.2011.02.030

Tetrahedron Letters 52 (2011) 1891–1894
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Tetrahedron Letters
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Cellulose-SO3H: an efficient and biodegradable solid acid for the synthesis
of quinazolin-4(1H)-ones
B. V. Subba Reddy a, , A. Venkateswarlu a, Ch. Madan a, A. Vinu b,c
⇑
a Division of Organic Chemistry, Indian Institute of Chemical Technology, Hyderabad 500 007, India
b International Center for Materials Nanoarchitectonics, WPI Research Center, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
c NIMS-IICT Materials Research Center, Indian Institute of Chemical Technology, Hyderabad 500 007, India
a r t i c l e i n f o
a b s t r a c t
Article history:
The condensation of 2-aminobenzamide with aldehydes or ketones has been achieved using cellulose-
sulfonic acid under mild reaction conditions to furnish 2,3-dihydroquinazolin-4(1H)-ones in good yields
with a high selectivity. The use of biodegradable solid acid catalyst, cellulosesulfonic acid makes this
method quite simple, more convenient, and practical. This catalyst was also found to be very active for
the synthesis of hydroxyalkylquinazolin-4-ones from cyclic enol ethers.
Received 2 December 2010
Revised 5 February 2011
Accepted 7 February 2011
Available online 12 February 2011
Ó 2011 Elsevier Ltd. All rights reserved.
Keywords:
Anthranilamide
Ketones
Aldehydes
Cellulose-SO3H
2,3-Dihydroquinazolinones exhibit a wide range of biological
activities, such as antitumor, antibiotic, antidefibrillatory, antipy-
retic, analgesic, antihypertonic, diuretic, antihistamine, antidepres-
sant, and vasodilating behavior.1 They play a key role in various
cellular processes. Furthermore, quinazolinone skeleton is fre-
quently found in various natural products (Fig. 1).2,3
O
N
O
N
N
N
O
N
N
Ph
Luotonin F
(-)-Benzomalvin A
Therefore, several efforts have been made to develop elegant
approaches for the synthesis of quinazolinone alkaloids.3 In addi-
tion, a variety of methods have been developed for the synthesis
of quinazolinone scaffolds.4,5 Of these, the condensation of 2-ami-
nobenzamide with aldehydes or ketones is one of the simplest and
direct methods for the synthesis of 2,3-dihydroquinazolin-4(1H)-
ones. Various acid catalysts, such as p-TSA/NaHSO3,6a TiCl4/Zn,6b
CuCl2,6c ionic liquid–water,6d and TFA,6e ammonium chloride,6f
and chiral phosphoric acids7 have been utilized to accomplish this
transformation. However, many of these methods involve the use
of expensive reagents, extended reaction times, high temperatures,
and also require tedious work-up procedures. Therefore, the devel-
opment of novel methods for the synthesis of quinazolin-4(3H)-
ones is of great importance because of their potential biological
and pharmaceutical activities.
O
O
H2NO2S
Cl
NH
NH
N
N
H
OH
Thiabutazide
2-(4-Hydroxybutyl)quinazolin-4-one
Figure 1. Examples of some natural products bearing quinazolin-4-one skeleton.
heterogeneous catalyst for the synthesis of quinolines, a-amino ni-
triles, aryl-14H-dibenzo[a.j]xanthenes, tetrahydroquinolines, and
functionalized pyrrolidines.9 However, there are no reports on
the use of cellulose-SO3H for the preparation of quinazolin-
4(1H)-ones under mild reaction conditions.
Following our interest on the catalytic applications of solid acid
catalysts,10 we herein report, for the first time, a novel method for
the synthesis of hydroxyalkylquinazolin-4-ones using a biodegrad-
able and recyclable solid acid catalyst, that is, cellulose-SO3H.
Initially, we have attempted the reaction of anthranilamide
with 3,4-dihydro-2H-pyran in the presence of cellulose-SO3H.
Recently, the use of heterogeneous catalysts has received a spe-
cial attraction as user-friendly catalysts because of recyclability,
operational simplicity, and minimal waste disposal.8 Very recently,
cellulose-SO3H has been introduced as a biodegradable solid acid
⇑
Corresponding author. Fax: +91 40 27160512.
E-mail address: basireddy@iict.res.in (B.V. Subba Reddy).
0040-4039/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tetlet.2011.02.030

1892
B. V. Subba Reddy et al. / Tetrahedron Letters 52 (2011) 1891–1894
isatin, cyclohexanone, and cyclopentanone. Interestingly, these
O
O
cyclic ketones underwent smooth coupling with anthranilamide
under similar conditions to furnish the corresponding 2-spiro-
2,3-dihydroquinazolin-4-ones in good yields (Table 2, entries
m–o). The results are summarized in Table 2 after optimizing
the reaction conditions with different aryl aldehydes and ke-
tones.11 It was found that all the reactions proceeded well at
Cellulose-SO3H
CH3CN, rt
NH2
NH
+
NH2
N
OH
O
1
3a
2
Scheme 1. Reaction of anthranilamide with 3,4-dihydro-2H-pyran.
room temperature except with D-glucal affording the correspond-
ing products in good yields (Tables 1 and 2). All the products
were fully characterized and confirmed by 1H NMR, 13C NMR,
IR, and mass spectroscopy. No significant change in yields was
observed when either ketones or substituted aryl aldehydes
were used. In the absence of cellulose-SO3H, no cyclized product
was observed even in refluxing acetonitrile. As solvent, acetoni-
trile gave the best results. It is noteworthy to highlight that
the catalyst could be recycled three times without significant
loss of activity. For example, the treatment of anthranilamide
(1 mmol) with p-chlorobenzaldehyde (1 mmol) in the presence
of cellulose-SO3H (50 mg) gave the 2-phenyl-2,3-dihydroquinaz-
olin-4-one in 90%, 87%, and 82% yields over three cycles. This
clearly shows the heterogeneous nature of the catalyst with
excellent recycling capability, which is the advantage of our
method over existing ones.
Interestingly, the reaction went to completion at room tempera-
ture and the desired 2-(4-hydroxybutyl)quinazolin-4-one 3a was
obtained in 65% yield (Scheme 1, Table 1 entry a).
This result provided the incentive to extend this process for
other enol ethers. Similarly, 2,3-dihydrofuran also reacted well
with anthranilamide to give the corresponding 2-(3-hydroxypro-
pyl)quinazolin-4-one (Table 1, entry b). Notably, 2-aminobenzene-
sulfonamide also participated well in this reaction (Table 1, entries
c and d). Next, we have attempted the cyclization of anthranila-
mide with 3,4,6-tri-O-acetyl-D-glucal under similar conditions.
Interestingly, the desired sugar substituted quinazolinone 3e was
obtained in 60% yield (Table 1, entry e).
The excellent catalytic activity of cellulose-SO3H in the
synthesis of hydroxyalkylquinazolin-4(1H)-ones prompted us
to investigate its use in the condensation of anthranilamide
with various aldehydes and ketones. Interestingly, several aro-
matic aldehydes, such as p-anisaldehyde, p-chlorobenzaldehyde,
m-phenoxybenzaldehyde, 2-naphthaldehyde, 2-furfural, 3,4,5-tri-
methoxybenzaldehyde, 2-nitrobenzaldehyde, and 4-nitrobenzal-
dehyde participated well in this reaction (Table 2, entries a–h).
Notably, acid sensitive cinnamaldehyde also gave the desired 2,3-
dihydroquinazolin-4-one in 82% yield (Table 2, entry j). The reac-
tion with aliphatic aldehydes, such as 3-phenylpropanaldehyde,
cyclohexanecarboxaldehyde, butyraldehyde worked well to fur-
nish the desired products in good yields (Table 2, entries i, k
and l). In all cases, 2,3-dihydroquinazolin-4-ones were obtained
exclusively in high yields (Scheme 2, Table 2).
In summary, we have demonstrated a novel protocol for the
preparation of 2,3-dihydroquinazolin-4-ones using cellulose-SO3H
as a recyclable solid acid catalyst.12 This method also describes
for the first time the synthesis of hydroxyalkylquinazolin-4-ones.
The use of cellulose-SO3H makes this method simple, convenient,
and economically viable for
a large scale synthesis of 2,3-
dihydroquinazolin-4-ones. The major advantages of the present
method are short reaction times, high yields, simplicity in operation,
cost-effective and mild reaction conditions.
Acknowledgments
This method works well with both electron-rich as well as
electron deficient aryl aldehydes (Table 2). Next, we have at-
tempted the coupling of anthranilamide with ketones, such as
A.V. thanks CSIR, New Delhi, for the award of a fellowship and
also the authors thank Dr. J. S. Yadav, Director, IICT Hyderabad
for his kind support.
Table 1
Cellulose-SO3H-catalyzed one-pot synthesis of hydroxyalkylquinazolinones
Entry
a
Anthranilamide
Enol eher
Product (3)a
Time (h)
1.0
Yieldb (%)
65
O
O
NH2
NH2
O
NH
N
O
O
OH
O
O
NH2
NH2
NH
N
b
c
1.5
1.0
1.5
60
62
57
OH
O
O
O
NH2
O
O
O
NH
S
S
NH2
N
OH
O
S
O
NH
S
O
NH2
d
OH
NH2
O
N
O
OAc
OAc
OAc
NH
NH2
NH2
60c
OH
e
12
N
OAc
O
AcO
All products were characterized by 1H NMR, IR, and mass spectroscopy.
Yield refers to pure products after chromatography.
a
b

B. V. Subba Reddy et al. / Tetrahedron Letters 52 (2011) 1891–1894
1893
Table 2
Cellulose-SO3H-catalyzed synthesis of dihydroquinazolinones
Entry
Anthranilamide (1)
Carbonyls (4)
Product (5)a
Time (min)
60
Yieldb (%)
O
CHO
O
NH2
NH2
NH
a
88
90
N
H
OMe
CHO
OMe
O
O
NH2
NH2
NH
b
55
N
H
Cl
Cl
O
CHO
O
NH2
NH2
NH
c
50
55
45
84
80
80
OPh
PhO
N
H
O
O
CHO
NH2
NH2
NH
d
e
N
H
O
O
CHO
O
NH2
NH2
NH
N
H
O
O
O
CHO
NH2
NH2
NH
OMe
OMe
f
50
92
OMe
OMe
MeO
N
H
OMe
O
CHO
NO2
O
NH2
NH2
NH NO2
NH
g
60
65
77
80
N
H
O
CHO
NO2
O
NH2
NH2
h
N
H
NO2
O
O
CHO
NH2
NH2
NH
NH
NH
NH
i
50
45
55
48
85
82
88
85
N
H
O
O
CHO
NH2
NH2
j
N
H
O
O
CHO
NH2
NH2
k
l
N
H
O
O
CHO
NH2
NH2
N
H
O
O
O
O
NH2
NH2
NH
O
m
50
87
N
NH
N
H
H
(continued on next page)

1894
B. V. Subba Reddy et al. / Tetrahedron Letters 52 (2011) 1891–1894
Table 2 (continued)
Entry
Anthranilamide (1)
Carbonyls (4)
Product (5)a
Time (min)
45
Yieldb (%)
82
O
O
O
NH2
NH2
NH
n
N
H
O
O
O
NH2
NH2
NH
o
40
78
N
H
a
All products were characterized by 1H NMR, IR and mass spectroscopy.
Yield refers to pure products after chromatography.
b
9. (a) Shaabani, A.; Rahmati, A.; Badri, Z. Catal. Commun. 2008, 9, 13; (b) Madhav, J.
V.; Reddy, Y. T.; Reddy, P. N.; Reddy, M. N.; Kuarm, S.; Crooks, P. A.; Rajitha, B. J.
Mol. Cat. A: Chem. 2009, 304, 85; (c) Kumar, A.; Srivastava, S.; Gupta, G.
Tetrahedron Lett. 2010, 51, 517; (d) Kumar, A.; Gupta, G.; Srivastava, S. J. Comb.
Chem. 2010, 12, 458.
10. (a) Reddy, B. V. S.; Venkateswarlu, A.; Kumar, G. G. K. S. N.; Vinu, A. Tetrahedron
Lett. 2010, 51, 6511; (b) Yadav, J. S.; Reddy, B. V. S.; Chaya, D. N.; Kumar, G. G. K.
S. N.; Naresh, P.; Jagadeesh, B. Tetrahedron Lett. 2009, 50, 1799; (c) Yadav, J. S.;
Reddy, B. V. S.; Satheesh, G. Tetrahedron Lett. 2004, 45, 3673; (d) Yadav, J. S.;
Reddy, B. V. S.; M Srinivas, M.; Prabhakar, A.; Jagadeesh, B. Tetrahedron Lett.
2004, 45, 6033; (e) Yadav, J. S.; Reddy, B. V. S.; Sunitha, V.; Reddy, K. S.;
Ramakrishna, K. V. S. Tetrahedron Lett. 2004, 45, 7947.
O
O
NH2
Cellulose-SO3H
CH3CN,rt
NH
+ RCHO
NH2
N
H
5
R
1
4
R = aryl, alkyl, naphthyl, cinnamyl, furanyl
Scheme 2. Reaction of anthranilamide with aldehydes.
11. General procedure: A mixture of carbonyl compound (1 mmol), anthranilamide
(1 mmol), and cellulose-SO3H (50 mg) in acetonitrile (5 mL) was stirred at
room temperature for a specified time (Table 1). After completion of the
reaction, as indicated by TLC, the catalyst was filtered and washed with ethyl
acetate (2 Â 10 mL) and the resulting filtrate was dried over Na2SO4 and
concentrated under vacuum. The product was purified by silica gel column
chromatography (50:50, hexane/ethyl acetate) to afford the pure 2,3-
dihydroquinazolin-4(1H)-one. The products thus obtained were characterized
by IR, NMR and mass spectroscopy. The spectral data were found to be
consistent with authentic samples.
References and notes
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3c (Table 1): Colorless liquid, 1H NMR (300 MHz, DMSO-D6):
d 7.44 (d,
J = 6.6 Hz, 1H), 7.19 (td, J = 8.6, 11.8 Hz, 1H), 6.78 (d, J = 8.1 Hz, 1H), 6.66 (t,
J = 7.7 Hz, 1H), 4.69 (t, J = 6.2 Hz, 2H), 1.38–0.82 (m, 6H); 13C NMR (75 MHz,
DMSO-D6): d 143.7, 132.5, 128.2, 123.6, 121.2, 116.1, 115.8, 65.7, 33.3, 32.1,
20.9.; IR (KBr): mmax 3404, 2941, 2874, 1647, 1488, 1221, 1030, 769, 639; MS
(ESI): 277 [M+Na]; HRMS Calcd for C11H14N2O3Na: 277.1253. Found: 277.1248.
3e (Table 1): (2S,3R,E)-2-hydroxy-5-(4-oxo-3,4-dihydroquinazolin-2-yl)pent-
4-ene-1,3-diyl diacetate: Semi-solid, 1H NMR (300 MHz, DMSO-D6): d 7.72
(brs, 1H), 7.63 (d, J = 7.9 Hz, 1H), 7.18 (t, J = 6.7 Hz, 1H), 6.68 (t, J = 6.7 Hz, 2H),
5.89 (dd, J = 16.8, 6.2 Hz, 1H), 5.19 (d, J = 5.6 Hz, 1H), 4.16–3.76 (m, 4H) 2.30 (s,
6H); 13C NMR (75 MHz, DMSO-D6): d 170.5, 169.5, 163.6, 147.9, 133.4, 131.7,
2. (a) Maskey, R. P.; Shaaban, M.; Grun-Wollny, I.; Laatsch, H. J. Nat. Prod. 2004, 67,
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Weaver, G. W. Org. Biomol. Chem. 2007, 5, 103; (c) Kshirsagar, U. A.; Argade, N.
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cited therein; (c) Larksarp, C.; Alper, H. J. Org. Chem. 2000, 65, 2773; (d)
Sadanandam, Y. S.; Reddy, K. R. M.; Rao, A. B. Eur. J. Org. Chem. 1987, 22, 169; (e)
Kalusa, A.; Chessum, N.;Jones, K. Tetrahedron Lett. 2008, 49, 5840; (f)Xia, Y.; Yang,
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Hackl, T.; Hamel, E.; Lee, K. H. Bioorg. Med. Chem. Lett. 2001, 11, 1193; (g) Liu, X.
W.; Fu, H.; Jiang, Y. Y.; Zhao, Y. F. Angew. Chem., Int. Ed. 2009, 48, 348.
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(b) Moore, J. A.; Sutherland, G. J.; Sowerby, R.; Kelly, E. G.; Palermo, S.; Webster,
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Davies, M. A.; Traber, J. E. J. Med. Chem. 1994, 19, 381; (d) Corbett, J. W.; Ko, S. S.;
Rodgers, J. D.; Gearhart, L. A.; Magnus, N. A.; Bachheler, L. T.; Diamond, S.;
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Jalil, R. J.; Voelter, W.; Saeed, M. Tetrahedron Lett. 2004, 45, 3475; (d) Chen, J.;
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128.7, 127.3, 114.4, 73.7, 69.3, 67.5, 20.9, 20.7.; IR(KBr):
1650, 1490, 1254, 1034, 760; MS (ESI): 347 [M+H]; HRMS Calcd for
17H19N2O6: 347.1243. Found: 347.1248.
mmax 3432, 3084, 2919,
C
5a (Table 2): 2-(4-Methoxyphenyl)-2,3-dihydroquinazolin-4(1H)-one: White
solid, m.p. 189–191 °C, 1H NMR (300 MHz, CDCl3+DMSO, 3:1): d 7.78 (brs, 1H),
7.64 (dd, J = 7.7 Hz, 1H), 7.43 (d, J = 8.6 Hz, 2H) 7.18 (t, J = 8.1 Hz, 1H), 6.88 (d,
J = 8.4 Hz, 2H), 6.63–6.73 (m, 2H), 5.71 (s, 1H), 3.78 (s, 3H) 13C NMR (75 MHz,
CDCl3+DMSO): d 163.9, 159.9, 147.3, 132.7, 127.7, 127.0, 117.2, 113.8, 113.0,
67.0, 54.4; IR (KBr): mmax 3443, 2924, 2853, 1656, 1612, 1511, 1385, 1247, 757;
MS (ESI): 255 [M+H]; HRMS Calcd for C15H15N2O2: 255.1133. Found: 255.1134.
5c (Table 2): 2-(3-Phenoxyphenyl)-2,3-dihydroquinazolin-4(1H)-one: Semi-
solid, 1H NMR (300 MHz, CDCl3+DMSO, 3:1):
d 7.87 (brs, 1H), 7.66 (dd,
J = 7.7 Hz, 1H), 7.16–7.35 (m, 6H), 7.08 (t, J = 7.6 Hz, 1H), 6.96 (d, J = 8.5 Hz, 2H),
6.91 (brs, 1H), 6.63–6.73 (m, 3H), 5.74 (s, 1H); 13C NMR (75 MHz,
CDCl3+DMSO): d 161.9, 154.8, 154.5, 145.8, 141.9, 131.4, 128.0, 125.5, 121.5,
119.9, 116.7, 115.4, 115.2, 112.6, 64.4; IR (KBr): mmax 3423, 3084, 2929, 2857,
1662, 1485, 1338, 1023, 764; MS (ESI): 317 [M+H]; HRMS Calcd for
C
20H17N2O2: 317.1290. Found: 317.1297.
5e (Table 2): 2-(Furan-2-yl)-2,3-dihydroquinazolin-4(1H)-one: Light yellow
solid, m.p. 120–121 °C: 1H NMR (300 MHz, CDCl3+DMSO, 3:1): d 8.06 (d,
J = 2.5 Hz, 1H), 7.71 (brs, 1H), 7.67 (dd, J = 7.7 Hz, 1H), 7.19 (t, J = 8.3 Hz, 1H),
6.70 (t, J = 8.1 Hz, 2H), 6.65 (brs, 1H), 6.29 (s, 2H), 5.75 (d, J = 3.2 Hz, 1H); 13C
NMR (75 MHz, CDCl3+DMSO): d 163.9, 152.8, 146.3, 142.0, 141.9, 133.0, 127.3,
117.8, 114.3, 109.7, 107.1, 60.8; IR (KBr): mmax 3416, 3259, 3034, 2921, 1650,
1611, 1467, 1386, 732; MS (ESI): 215 [M+H]; HRMS Calcd for C12H11N2O2:
215.0820. Found: 215.0830.
7. (a) Cheng, X.; Vellalath, S.; Goddard, R.; List, B. J. Am. Chem. Soc. 2008, 130,
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12. The catalyst, cellulose-sulfonic acid, was prepared according to the literature
procedure: Shaabani, A.; Maleki, A. Applied Catalysis A: General 2007, 331, 149.