A stereoselective three-component reaction: One-pot synthesis of cis-isoquinolonic acids catalyzed by silica sulfuric acid under mild and heterogeneous conditions

Article abstract of DOI:10.1002/jhet.5570430129

A mild and stereoselective three-component one-step synthesis of cis-isoquinolonic acid using silica sulfuric acid as a heterogeneous catalyst from an aldehyde, amine and homophthalic anhydride in acetonitrile is described. This new method produces pure p

Full text of DOI:10.1002/jhet.5570430129

Jan-Feb 2006
A Stereoselective Three-component Reaction: One-pot Synthesis of
cis-Isoquinolonic Acids Catalyzed by Silica Sulfuric Acid under Mild
and Heterogeneous Conditions
187
Javad Azizian,* Ali A. Mohammadi, Ebrahim Soleimani, Ali R. Karimi,
and Mohammad R. Mohammadizadeh
Department of Chemistry, Faculty of Science, Shahid Beheshti University, P. O. Box 19395-4716, Tehran, Iran
E-mail: j-azizian@cc.sbu.ac.ir
Received April 18, 2005
A mild and stereoselective three-component one-step synthesis of cis-isoquinolonic acid using silica sul-
furic acid as a heterogeneous catalyst from an aldehyde, amine and homophthalic anhydride in acetonitrile is
described. This new method produces pure products in high yields (81-91%).
J. Heterocyclic Chem., 43, 187 (2006).
During recent years, the use of silica sulfuric acid as cat-
describe a general and practical route for the cycloconden-
sation reaction using silica sulfuric acid as the catalyst [12].
This is a novel, one-pot combination that not only preserves
the simplicity of cycloaddition’s multi-component reaction
but also consistently produces excellent yields of the cis-
isoquinolonic acids. In the presence of the silica sulfuric
acid (0.23 g, equal to 0.6 mmol), the reaction of homoph-
thalic anhydride 1 (1 mmol), aldehyde 2a-m (1 mmol), and
amine 3a-m (1 mmol) in acetonitril was carried out in a
one-pot condensation at room temperature (Scheme 1).
alysts or promoters in organic synthesis has attracted great
interest from many chemists [1]. Silica sulfuric acid can
enhance the reactivity and selectivity of many types of
reaction, such as oxidation, reduction, carbon-carbon bond
formation, cycloaddition and protection.
Isoquinolonic acid and the derivatives are pharmacolog-
ically important and have biological activities [2] includ-
ing anti-inflammatory and psychotropic behaviour. In
addition, isoquinolonic acids have been reported as start-
ing materials for the total synthesis of natural compounds
such as nitidine chloride [3], 4-epicorynoline, corynoline,
6-oxocorynoline [4], decumbenine B [5]. Therefore, many
synthetic methods for preparing such compounds have
been developed [6]. The cycloaddition of homophthalic
anhydride with imines has been reported in the presence
ofa catalytic amount of Lewis acids (such as ZnCl FeCl ,
2,
3
AlCl ) bases (TEA, DIEA) etc., protic acids (CH COOH,
3
3
HCl), or absence catalyst, which often produce a mixture
of cis-and trans-isomers. Recently, BF -Et O [7] has been
The results (Table 1) show a series of aromatic aldehy-
des and amines that undergo the cyclocondensation to give
excellent yields (81-91%) of the products. The all cis-
stereochemistry of cycloadducts 4 was attributed from the
two doublets (J=4.6-6.9 Hz) observed close to 4.52-4.99
ppm and 4.96-5.97 ppm, for the H-3 and H-4 hydrogen
atoms, respectively.
3
2
employed for the preparation of trans-isoquinolonic acids,
and trimethyl orthoformate [8], ionic liquids [9a] and
ytteribium (III) triflate [9b] have been employed for the
synthesis of cis-isomers.
In connection with our ongoing work on multi-compo-
nent condensations (MCCs) [10], we now wish to report a
facile, rapid and stereoselective one-pot three-component
procedure for the preparation of cis-isoquinolonic acids
derivatives with silica sulfuric acid as a heterogeneous,
non-toxic, reusable, inexpensive and easily available
reagent, at room temperature. Very recently, we have
reported the preparation of cis-isoquinolonic acids by the
reaction of homophthalic anhydride with imines in the
This new procedure is also simple to operate. The
work-up consists of simple filtration and the catalyst is
reusable and can be applied several times without any
decrease in the yield of the reactions. All the products
1
13
were characterized by IR, H NMR, C NMR, MS, and
elemental analyses [13]. After the reaction was com-
pleted, the cis-isoquinolonic acids 4a-m precipitated
from the reaction mixture.
presence of KAl(SO ) .12H O [11]. In this paper, we
4 2
2

188
J. Azizian, A. A. Mohammadi, E. Soleimani, A. R. Karimi, and M. R. Mohammadizadeh
Vol. 43
Table 1
The Reaction of Homophthalic Anhydride, Amines and Aldehydes
2
1
a
Product
R
R
Time
(h)
Yield
(%)
M.P (°C)
Lit. M .P
(°C)
4
a
b
c
d
e
f
g
h
i
Ph
Ph
Ph
Ph
Ph
4-ClC H
7
6.5
6
7.5
8
8.5
9
7.5
7
88
90
91
88
87
84
85
86
89
87
81
201-3
200-1
187-8
179-80
180-1
198 [8]
182 [8]
178 [8]
6
4
4-MeC H
6
4
PhCH
PhCH
-
-
-
-
-
-
-
-
2
4-ClC H
6
4
2
Ph
Ph
PhCH CH
168-70
2
2
Benzimidazol
4-MeC H
222-4 dec.
246-8 dec.
225-6 dec.
210-1 dec.
216-8
4-NO C H
2
6
4
6 4
4-BrC H
4-ClC H
6
4
6 4
l
m
3-ClC H
4-ClC H
6 4
8
8.5
6
4
2-BrC H
PhCH
6
4
2
a
Yields of pure isolated product based on homophthalic anhydride.
Hz, H ), 5.49(d, 1H, J=6.9 Hz, H ), 7.01-7.30(m, 10H), 7.57-
7.60(m, 3H), 8.07(d, 1H, J=8.7 Hz), 12.04(broad, 1H). C NMR
In summary, we have described a successful strategy,
3
4
13
efficient and convenient green synthesis for the prepara-
tion of tetrahydroisoquinolonic acids in a valuable three-
component cyclocondensation reaction of homophthalic
anhydride, aldehydes and amines using the inexpensive,
non-toxic and easily available silica sulfuric acid catalyst.
The method offers several advantages including high yield
of products, a recyclable catalyst and easy experimental
work-up procedure. Surprisingly, this reaction is stereose-
lective in the preparation of cis-isoquinolonic acids, since
no detectable amount of trans-isomers, which makes it a
useful process for the synthesis of cis-isoquinolonic acids.
(DMSO) δ : 49.54, 65.12, 126.60, 128.10, 128.24, 128.36,
C
128.39, 128.44, 128.67, 129.47, 129.60, 132.64, 135.90, 136.15,
+
137.35, 139.55, 163.20, 171.10. MS (m/z, %): 343 (M , 75), 298
(30), 207 (25), 181 (100), 134 (45), 118 (35), 105 (35), 90 (25),
77 (80), 63 (35), 51 (50), 39(35).
Anal. Calcd. for C
H NO : C, 76.95; H, 4.99; N, 4.08.
22 17 3
Found: C, 76.78; H, 4.90; N, 4.00.
2-(4-Chlorophenyl)-1-oxo-3-phenyl-1,2,3,4-tetrahydro-isoquino-
line-4-carboxylic Acid (4b).
-1
White powder, yield 90%, mp 200-1 ˚C, IR(KBr), (ν
cm ):
max /
1
3070, 2913, 1723, 1630. H NMR (DMSO) δ : 4.86(d, 1H, J=4.6
Hz, H ), 5.52(d, 1H, J=4.6 Hz, H ), 7.04-7.57(m, 12H), 8.06(d,
1H, J=7.3 Hz), 12.91(broad, 1H). C NMR (DMSO) δ : 49.62,
64.57, 128.19, 128.22, 128.37, 128.43, 128.53, 128.67, 129.00,
129.38, 129.75, 131.30, 132.94, 134.94, 137.51, 140.86, 163.52,
H
3
4
13
EXPERIMENTAL
C
Melting points were measured on the Electro thermal 9100
apparatus and are uncorrected. IR spectra were measured on a
+
170.93. MS (m/z, %): 377 (M , 30), 358 (20), 333 (60), 250 (20),
214 (100), 178 (50),138 (30), 118 (95), 111 (80), 90 (95), 75 (80),
63 (85), 51 (70), 39(55).
1
13
Shimadzu IR-470 Spectrophotometer. H NMR and C NMR
spectra were determined on Bruker 500 DRX AVNCE instrument
at 500 and 125 MHz, respectively. Elemental analyses were per-
formed using a Heracus CHN-O-Rapid analyzer.
Anal. Calcd. for C H NO Cl: C, 69.94; H, 4.27; N, 3.71.
22 16
3
Found: C, 69.87; H, 4.18; N, 3.60.
1-Oxo-3-phenyl-2-p-tolyl-1,2,3,4-tetrahydro-isoquinoline-4-car-
boxylic Acid (4c).
General Procedure for the Preparation of cis-Isoquinolonic
Acids.
-1
White powder, yield 91%, mp 187-8 ˚C, IR(KBr), (ν
cm ):
max /
A mixture of homophthalic anhydride (1 mmol, 162 mg), alde-
hydes (1.2 mmol), amine (1 mmol), silica sulfuric acid (0.23 g)
and acetonitrile (8-10 ml) in a 25 ml flask was stirred at room
temperature for the time period as indicated in Table 1. After
completion the reaction (monitored by TLC, ethyl acetate/n-
hexane 1/1), the solvent was evaporated under reduced pressure,
then water (25 ml) was add to the reaction mixture and the result-
ing solid was separated by filtration. The crude product was
washed with ether to afford pure cis-isoquinolonic acids in 81-
91% yields.
1
3010, 2910, 1723, 1614. H NMR (DMSO) δ : 2.23(s, 3H, CH ),
H
3
4.93(d, 1H, J=5.7 Hz, H ), 5.43(d, 1H, J=5.7 Hz, H ), 6.99-
3
4
7.15(m, 9H), 7.45-7.60(m, 3H), 8.05(d, 1H, J=7.6 Hz),
13
12.90(broad, 1H). C NMR (DMSO) δ : 21.03, 49.44, 65.02,
C
127.64, 128.02, 128.22, 128.26, 128.33, 128.41, 128.57, 129.57,
129.69, 132.68, 134.70, 136.35, 137.76, 139.64, 163.31, 170.88.
MS (m/z, %): 357 (M , 30), 313 (35), 236 (25), 208 (45), 195
+
(100), 178 (70), 134 (30), 118 (75), 91 (85), 77 (95), 63 (50), 51
(70), 39(55).
Anal. Calcd. for C
H NO : C, 77.29; H, 5.36; N, 3.92.
23 19 3
Found: C, 77.17; H, 5.29; N, 3.85.
Spectral Data for Products.
1-Oxo-2,3-diphenyl-1,2,3,4-tetrahydro-isoquinoline-4-carbox-
2-Benzyl-1-oxo-3-phenyl-1,2,3,4-tetrahydro-isoquinoline-4-car-
ylic Acid (4a).
boxylic Acid (4d).
-1
-1
White powder, yield 88%, mp 201-3 ˚C, IR(KBr), (ν
cm ):
White powder, yield 88%, mp 179-80 ˚C, IR(KBr), (ν
cm ):
max /
max /
1
1
3020, 2915, 1723, 1633. H NMR (DMSO) δ : 4.94(d, 1H, J=6.9
3025, 2910, 1742, 1613. H NMR (DMSO) δ : 3.75(d, 1H, J=15.3
H
H

Jan-Feb 2006
A Stereoselective Three-component Reaction
189
Hz, CH ), 4.69(d, 1H, J=6.0 Hz, H ), 4.96(d, 1H, J=6.0 Hz, H ),
Hz, H ), 7.09(m, 4H), 7.31(d, 2H, J=8.2), 7.49-7.61(m, 3H),
2
3
4
4
5.31(d, 1H, J=15.3 Hz, CH ), 6.96-7.57(m, 13H), 8.08(d, 1H,
8.03(d, 2H, J=8.2 Hz), 8.08(d, 1H, J=7.2 Hz), 12.52(broad, 1H).
2
13
13
J=7.5 Hz), 12.99(broad, 1H). C NMR (DMSO) δ : 48.55, 48.57,
C NMR (DMSO) δ : 48.74, 63.40, 123.04, 127.15, 127.43,
C
C
61.18, 127.69, 127.93, 127.97, 128.03, 128.25, 128.50, 128.75,
127.73, 127.83, 129.10, 129.27, 132.38, 136.01, 138.59, 144.92,
+
129.01, 129.18, 132.52, 134.15, 137.79, 163.59, 170.72. MS (m/z,
146.95, 162.68, 170.20. MS (m/z, %): 402 (M , 10), 383 (15),
+
%): 358 (M , 25), 357 (35), 269 (30), 207 (25), 136 (30), 118 (80),
356 (50), 295 (40), 252 (25), 240 (50), 193 (30), 165 (20), 118
(70), 106 (100), 90 (60), 77 (30), 63 (35), 51 (30), 39 (50).
Anal. Calcd. for C H N O : C, 68.65; H, 4.51; N, 6.96.
116 (75), 91 (100), 77 (35), 62 (30), 51 (35), 39(30).
Anal. Calcd. for C
H NO : C, 77.29; H, 5.36; N, 3.92.
23 18
2 5
23 19 3
Found: C, 68.59; H, 4.47; N, 6.87.
Found: C, 77.20; H, 5.27; N, 3.83.
3-(4-Bromophenyl)-2-(4-chlorophenyl)-1-oxo-1,2,3,4-tetrahy-
2-Benzyl-3-(4-chlorophenyl)-1-oxo-3-phenyl-1,2,3,4-tetrahydro-
dro-isoquinoline-4-carboxylic Acid (4i).
isoquinoline-4-carboxylic Acid (4e).
-1
White powder, yield 89%, mp 225-6 dec.˚C, IR(KBr), (ν
White powder, yield 87%, mp 180-1 ˚C, IR(KBr), (ν
cm ):
max
max /
-1
1
1
cm ): 3065, 2920, 1723, 1630. H NMR (DMSO) δ : 4.86(d,
3050, 2905, 1737, 1608. H NMR (DMSO) δ : 3.83(d, 1H,
J=15.3 Hz, CH ), 4.70(d, 1H, J=6.2 Hz, H ), 4.99(d, 1H, J=6.2
Hz, H ), 5.24(d, 1H, J=15.3 Hz, CH ), 6.94-7.55(m, 13H), 8.07(d,
1H, J=7.5 Hz), 13.02(broad, 1H). C NMR (DMSO) δ : 48.52,
48.72, 60.55, 127.69, 128.03, 128.10, 128.49, 128.71, 128.97,
129.03, 130.08, 132.65, 133.39, 133.91, 136.24, 137.67, 163.46,
/
H
H
1H, J=4.9 Hz, H ), 5.54(d, 1H, J=4.9 Hz, H ), 6.94-6.99(m, 4H),
3
4
2
3
7.20-7.28(m, 4H), 7.36-7.59(m, 5H), 8.05(d, 1H, J=7.5 Hz),
4
2
13
13
2.43(broad, 1H). C NMR (DMSO) δ : 48.87, 63.17, 127.57,
C
C
127.68, 127.81, 128.48, 128.57, 128.96, 129.21, 129.99, 130.81,
131.00, 132.45, 134.11, 136.40, 139.38, 162.80, 170.24. MS
+
+
(m/z, %): 456 (M , 15), 412 (55), 345 (50), 301 (60), 267 (45),
170.69. MS (m/z, %): 391 (M , 15), 347 (40), 242 (40), 207 (30),
257 (35), 223 (25), 193 (30), 178 (20), 118 (60), 106 (100), 90
(50), 77 (35), 63 (30), 51 (30), 39 (55).
178 (35), 118 (45), 106 (45), 91 (100), 65 (50), 51 (30), 39(30).
Anal. Calcd. for C H NO Cl: C, 70.50; H, 4.63; N, 3.57.
23 18
3
Anal. Calcd. for C H NO BrCl: C, 57.86; H, 3.31; N, 3.07.
Found: C, 70.43; H, 4.54; N, 3.51.
22 15
3
Found: C, 57.78; H, 3.22; N, 2.98.
1-Oxo-2-ethylphenyl-3-phenyl-1,2,3,4-tetrahydro-isoquinoline-
4-carboxylic Acid (4f).
3-(3-Chlorophenyl)-2-(4-chlorophenyl)-1-oxo-1,2,3,4-tetrahy-
dro-isoquinoline-4-carboxylic Acid (4l).
-1
White powder, yield 84%, mp 168-70 ˚C, IR(KBr), (ν
cm ):
max /
1
White powder, yield 87%, mp 210-1 dec.˚C, IR(KBr), (ν
3025, 2910, 1738, 1614. H NMR (DMSO) δ : 2.67(m, 1H,
CH ), 2.86-2.92(m, 1H, CH ), 2.98-3.04(m, 1H, CH ), 4.01-
max
H
-1
1
cm ): 3040, 2915, 1722, 1630. H NMR (DMSO) δ : 4.83(d,
/
H
2
2
2
1H, J=5.3 Hz, H ), 5.60(d, 1H, J=5.3 Hz, H ), 7.01(d, 1H, J=7.2
4.06(m, 1H, CH ), 4.52(d, 1H, J=6.2 Hz, H ), 4.98(d, 1H, J=6.2
3
4
2
3
Hz), 7.10(s, 1H), 7.20-7.26(m, 4H), 7.36-7.38(m, 2H), 7.49-
Hz, H ), 6.97(d, 2H, J=6.2 Hz), 7.16-7.19(m, 6H), 7.25-7.28(m,
4
13
7.62(m, 3H), 8.05(d, 1H, J=7.7), 12.53(broad, 1H). C NMR
2H), 7.41-7.44(m, 1H), 7.49(m, 2H), 8.02(d, 1H, J=6.8 Hz),
13
(DMSO) δ : 49.09, 62.99, 126.53, 127.53, 127.75, 127.81,
12.91(broad, 1H). C NMR (DMSO) δ : 34.05, 48.14, 48.45,
C
C
127.86, 127.91, 128.43, 128.58, 129.18, 129.92, 130.76, 132.50,
62.00, 126.73, 127.70, 127.84, 128.24, 128.34, 128.63, 128.67,
128.89, 129.08, 129.40, 132.31, 134.06, 137.74, 139.54, 163.13,
170.79. MS (m/z, %): 371 (M , 10), 353 (15), 327 (25), 280 (35),
+
134.27, 139.50, 139.90, 162.92, 170.32. MS (m/z, %): 411 (M ,
+
15), 367 (25), 333 (40), 299 (45), 257 (45), 244 (50), 223 (35),
178 (35), 165 (25), 118 (100), 111 (25), 90 (45), 77 (30), 63 (30),
51 (35), 39 (50).
236 (80), 221 (30), 207 (60), 174 (40), 146 (25), 118 (40), 91
(100), 92 (30), 65 (30), 51 (30), 44 (30), 39(25).
Anal. Calcd. for C H NO Cl : C, 64.09; H, 3.67; N, 3.40.
22 15
3
2
Anal. Calcd. for C
H NO : C, 77.49; H, 6.50; N, 3.61.
25 25 3
Found: C, 64.00; H, 3.57; N, 3.32.
Found: C, 77.41; H, 6.43; N, 3.57.
2-Benzyl-3-(2-bromophenyl)-1-oxo-1,2,3,4-tetrahydro-isoquino-
line-4-carboxylic Acid (4m).
2-(1H-Benzoimidazol-yl)-1-oxo-3-phenyl-1,2,3,4-tetrahydro-
isoquinoline-4-carboxylic Acid (4g).
-1
White powder, yield 81%, mp 216-8 ˚C, IR(KBr), (ν
cm ):
max /
White powder, yield 85%, mp 222-4 dec.˚C, IR(KBr), (ν
max
1
3060, 2925, 1735, 1610. H NMR (DMSO) δ : 3.71(d, 1H,
J=15.2, CH ), 4.61(d, 1H, J=6.5 Hz, H ), 5.32(d, 1H, J=15.2 Hz,
-1
1
H
cm ): 3060, 2915, 1700, 1657. H NMR (DMSO) δ : 4.61(d,
/
H
2
3
1H, J=6.5 Hz, H ), 5.96(d, 1H, J=6.5 Hz, H ), 7.29-7.43(m, 7H),
3
4
CH ), 5.43(d, 1H, J=6.5 Hz, H ), 6.95(m, 1H), 7.14-7.34(m, 8H),
2
4
7.47-7.57(m, 3H), 7.65(m, 1H), 7.95(d, 1H, J=7.7 Hz), 8.03(d,
13
7.50-7.60(m, 3H), 8.08(d, 1H, J=7.6 Hz), 12.50(broad, 1H).
C
13
1H, J=7.6 Hz), 12.53(broad, 1H). C NMR (DMSO) δ : 49.19,
C
NMR (DMSO) δ : 47.67, 47.78, 58.09, 124.32, 127.18, 127.37,
C
79.08, 80.35, 124.91, 126.27, 127.28, 128.08, 128.21, 128.72,
128.93, 128.98, 129.02, 129.23, 129.83, 130.22, 134.40, 134.85,
137.26, 137.97, 163.97, 171.58. MS (m/z, %): 383 (M , 10), 368
127.48, 127.57, 127.70, 128.02, 128.24, 128.38, 128.60, 130.01,
132.30, 132.56, 133.68, 135.96, 136.72, 162.91, 169.98. MS
+
+
(m/z, %): 435 (M , 15), 391 (15), 356 (50), 345 (10), 312 (35),
(20), 313 (15), 250 (35), 178 (35), 118 (100), 105 (60), 90 (95),
77 (75), 63 (55), 51 (65), 39(45).
302 (10), 278 (35), 261 (10), 234 (40), 206 (45), 178 (55), 118
(20), 106 (35), 91 (100), 65 (45), 51 (35), 39 (30).
Anal. Calcd for C H N O : C, 72.05; H, 4.47; N, 10.96.
23 17
3 3
Anal. Calcd. for C H NO Br: C, 63.32; H, 4.16; N, 3.21.
23 18
3
Found: C, 71.91; H, 4.40; N, 10.87.
Found: C, 63.23; H, 4.10; N, 3.13.
3-(4-Nitrophnyl)-1-oxo-2-p-tolyl-1,2,3,4-tetrahydro-isoquinoline-
4-carboxylic acid (4h).
REFERENCES AND NOTES
White powder, yield 86%, mp 246-8 dec.˚C, IR(KBr), (ν
max
-1
1
cm ): 3065, 2915, 1723, 1630, 1598. H NMR (DMSO) δ :
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H
2.23(s, 3H, CH ), 4.99(d, 1H, J=5.1 Hz, H ), 5.97(d, 1H, J=5.1
3
3

190
J. Azizian, A. A. Mohammadi, E. Soleimani, A. R. Karimi, and M. R. Mohammadizadeh
Vol. 43
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