MCM-41-SO3H as a nanoreactor for the one-pot, solvent-free synthesis of 1,8-dioxo-9-aryl decahydroacridines

Article abstract of DOI:10.1002/jhet.692

One-pot four-component synthesis of 1,8-dioxo-9-aryl decahydroacridines in solvent-free condition was efficiently performed in the presence of MCM-41-SO₃H as a nanocatalyst and nanoreactor in good yields. The method provides several advantages

Full text of DOI:10.1002/jhet.692

January 2012
MCM-41-SO3H as a Nanoreactor for the One-Pot, Solvent-Free
Synthesis of 1,8-Dioxo-9-aryl Decahydroacridines
111
Shahnaz Rostamizadeh,* Asiyeh Amirahmadi, Nasrin Shadjou,
and Ali M. Amani
Department of Chemistry, K. N. Toosi University of Technology, Tehran, Iran
*E-mail: rostamizadeh@hotmail.com
Received April 23, 2010
DOI 10.1002/jhet.692
Published online 13 October 2011 in Wiley Online Library (wileyonlinelibrary.com).
One-pot four-component synthesis of 1,8-dioxo-9-aryl decahydroacridines in solvent-free condition
was efficiently performed in the presence of MCM-41-SO3H as a nanocatalyst and nanoreactor in good
yields. The method provides several advantages such as low cost, operational and experimental simplic-
ity, high yields, and short reaction times.
J. Heterocyclic Chem., 49, 111 (2012).
INTRODUCTION
ganic moieties [11]. Although several types of solid sul-
fonic acids have been created in recent years, there have
been only a few reports about their applications as cata-
lyst in chemical transformations. Furthermore, to the
best of our knowledge, there is no report on the use of
these materials as nanocatalysts in the synthesis of 1,8-
dioxo decahydroacridines.
1,8-Dioxo-9-aryl decahydroacridines and their deriva-
tives are well-known polyfunctionalized 1,4-dihydropyri-
dine derivatives that are widely prescribed as calcium
channel blockers and used for the treatment of hyperten-
sion and defibrillation [1]. In addition, acridines are im-
portant compounds reported to have antitumor properties
[2]. Reportedly, the conventional synthesis of 1,4-dihy-
dropyridine derivatives was performed in organic sol-
vents such as HOAc [3], CH3CN [4], DMF [5], and
water [6]. There has been considerable interest for fur-
ther research toward simple procedure, low-catalyst
loading, and using different substrates for the synthesis
of 1,8-dioxo-9-aryl decahydroacridines.
In continuation of our work to develop new and eco-
friendly synthetic methodologies toward different heter-
ocyclic compounds [12], herein, we report a novel,
green, facile, and an efficient one-pot method for the
synthesis of 1,8-dioxo-9-aryl decahydroacridines deriva-
tives from readily available starting materials, dimedone,
ammonium acetate, and an aromatic aldehyde in the
presence of MCM-41-SO3H as a nanoctalyst under sol-
vent-free conditions. (Scheme 1)
In recent years, more attractive possibilities have been
arisen by the development of various new silica materi-
als with ordered structure [7]. One of the best-known
examples is MCM-41, which is a structurally well-or-
dered mesoporous material with a narrow pore size dis-
tribution between 1.5 and 10 nm, and a very high-sur-
face area up to 1500 m2 gꢀ1 [8]. It has been proven that
RESULTS AND DISCUSSION
Compared with known methods, our procedure is rep-
resenting an expedient method for certain acridinedione
derivatives with new application for a catalyst that has
not been applied for this purpose till now. Additionally,
the work covers today’s basic trends in chemistry, such
as environmentally benign systems and economical
approaches with short workup procedures and higher
yields.
¨
Si-MCM-41 lacks Bronsted acid sites and exhibits only
weak hydrogen-bonding-type sites [9,10]. An additional
possibility to develop acidic solids is the modification of
the surface of suitable supporting materials, as the
chemical functionalities of these materials can be uni-
formly modified by covalent anchoring of different or-
C
V
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112
S. Rostamizadeh, A. Amirahmadi, N. Shadjou, and A. M. Amani
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Scheme 1. Four-component one-step synthesis of 1,8-dioxo-9-aryl
decahydroacridines.
Table 2
The effect of the solvent for the synthesis of 4k in the presence of
0.005-g catalyst.
Solvent
Time (min)
Yield (%)
EtOH (reflux)
CH3CN (reflux)
H2O (reflux)
Solvent free
140
130
195
10
85
70
79
98
¨
ent Bronsted acidity of ASO3H groups, which are capa-
ble of bonding with the carbonyl oxygen of the chalcone,
generation of ionic intermediates is assisted by activation
of the reactants. In other words, ionic intermediates are
generated inside the nanoreactor by sufficient energy
released during the collapse and strong polarity of the
ASO3H groups. Second, the Michael addition of the
enamine to the chalcone leads to the formation of inter-
mediate (3). Finally, ring closure, together with water,
elimination gives the product (4). Therefore, under this
reaction condition and by using this nanocatalyst, the
reaction rates and yields are enhanced. (Scheme 2).
During our investigation, at first, we chose 4-chloro-
benzaldehyde (1 mmol), dimedone (2 mmol), and am-
monium acetate (3 mmol) under solvent-free conditions
as model reactants and examined the effect of the
amount of MCM-41-SO3H, in which the optimum
amount of catalyst was 0.005 g as shown in Table 1.
To evaluate the effect of solvent, we examined differ-
ent solvents for the synthesis of 1,8-dioxo-9-aryl deca-
hydroacridines in the presence of catalyst (Table 2).
According to our findings, solvent-free conditions gave
the best result for this transformation.
CONCLUSION
In conclusion, we have used MCM-41-SO3H as an
effective nanocatalyst for the one-pot multicomponent
synthesis of 1,8-dioxo-9-aryl decahydroacridine deriva-
tives. This catalyst is highly efficient, easily available,
economical, and requires mild reaction condition. The
products were also formed in excellent yields with short
reaction times. This method offers several advantages,
such as omitting toxic solvents or catalyst, very simple
work-up and needs no chromatographic method for puri-
fication of the products. The starting materials are also
inexpensive and commercially available.
Subsequently, to optimize the reaction temperature, a
mixture of 4-chlorobenzaldehyde (1 mmol), dimedone
(2 mmol), ammonium acetate (3 mmol), and MCM-41-
SO3H (0.005 g) were mixed and heated in a paraffin
bath at different temperature (Table 3). According to the
data, the optimum temperature was selected as 110ꢁC.
All of the reactions were carried out within 10–110
min and no by-product was observed by TLC analysis.
The reaction worked well with electron-withdrawing
(Cl, CN) as well as electron-donating (Me, MeO)
groups, giving various acridine derivatives in 60–98%
yields. As shown in Table 4, the method is general and
includes a variety of functional groups.
EXPERIMENTAL
General remarks. Melting points were recorded on a Buchi
B-540 apparatus. IR spectra were recorded on an ABB Bomem
Model FTLA200-100 instrument. 1H NMR and 13C NMR
spectra were measured on a Bruker DRX-300 spectrometer, at
300 and 75 MHz, using TMS as an internal standard. Chemi-
cal shifts (d) were reported relative to TMS, and coupling
It seems that at first the reaction of 1 mmol of dime-
done with 1 mmol of an aldehyde as well as the reaction
of 1 mmol dimedone with an ammonium acetate resulted
in the formation of chalcone (1) and enamine (2) inside
the nanocatalyst channels. Then, together with, the inher-
Table 3
Table 1
The effect of reaction temperature for the synthesis of 4k in the
presence of 0.005-g catalyst.
Comparison of the amount of the catalyst and yields for the
synthesis of 4k.
Temperature (ꢁC)
Time (min)
Yield (%)
Amount of catalyst (g)
Time (min)
Yield (%)
80
90
35
25
25
10
15
82
86
90
98
98
–
55
15
15
10
80
80
85
95
0.001
0.003
0.005
100
110
116
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MCM-41-SO3H as a Nanoreactor for the One-Pot, Solvent-Free Synthesis
of 1,8-Dioxo-9-aryl Decahydroacridines
113
Table 4
The reaction time and the yield (%) of 1,8-dioxo-9-aryl decahydroacridines product.
Product
Ar
Time
Yielda (%)
M.P. (ꢁC) found
M.P. (ꢁC) reported
4a
4b
4c
4d
4e
2,3-Di-Cl2AC6H4A
4-AcetamidAC6H4A
4-CNAC6H4A
10
15
80
75
87
94
60
>323
–
331–333 [14]
324–326 [14]
341–342
328–330
165–167
296–298
25
15
4-BnAOAC6H4A
–
–
110
4f
20
20
98
97
>334
–
–
4g
305–307
4h
4j
4k
4l
4m
4n
4o
4p
2,4-Di-ClAC6H4
2-ClAC6H4A
4-ClAC6H4A
4-BrAC6H4A
4-OCH3AC6H4A
4-CH3AC6H4A
3-OHAC6H4A
4-OHAC6H4A
15
10
10
10
10
20
15
15
88
96
95
92
88
88
82
61
>321
309–310
303–305
330–332
311–313
332
>321 [15]
231–233 [16]
300–302 [17]
>300 [17]
274–275 [3(b)]
>300 [18]
>300 [19]
>302
>304
>300 [18]
a Isolated yield.
Scheme 2. A provisional mechanisms for the synthesis of 1,8-dioxo-9-aryl decahydroacridines product.
Journal of Heterocyclic Chemistry
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S. Rostamizadeh, A. Amirahmadi, N. Shadjou, and A. M. Amani
Vol 49
constants (J) were reported in hertz (Hz). Mass spectra were
recorded on a Shimadzu QP 1100 EX mass spectrometer with
70-eV ionization potential.
50.04, 105.27, 110.44, 118.94, 128.67, 131.53, 149.87, 152.40,
194.28 MS (EI): m/e ¼ 374 (9) [Mþ], 273 (25), 272 (100), 271
(40), 140 (17), 102 (15), 83 (27).
Synthesis and functionalization of MCM-41. In the pres-
ent work, MCM-41 was modified to covalently anchor sulfonic
acid on the inside surface of channels to provide the silica-sup-
3,3,6,6-Tetramethyl-9-(4-(benzyloxy)phenyl)-1,2,3,4,5,6,7,8,
9,10-decahydroacridin-1,8-dione (4d). Yellow solid, M.P.165–
167ꢁC, (KBr, cmꢀ1) Vmax: 3604, 3352, 3286, 3029, 2952,
2859, 1611, 1H NMR (300 MHz; CDCl3): d ¼ 0.83 (6H, s,
2CH3), 0.95 (6H, s, 2CH3), 2–2.30 (8H, m, 4CH2), 4.85(2H, s,
CH2), 4.85 (2H, s, CH2), 5.06 (1H, s, CH), 6.80 (2H, d, J ¼
8.63 Hz, 2CH), 7.26 (2H, d, J ¼ 8.65 Hz, 2CH), 7.31 (5H, m,
5CH), 8.30 (1H, s, NH). 13C NMR (75 MHz, CDCl3): 27.07,
29.52, 32.54, 32.69, 40.48, 50.87, 69.84, 113.15, 114.09,
127.67, 127.87, 128.46, 128.91, 136.97, 139.41, 149.44,
156.98, 196.18 MS (EI): m/e ¼ 455 (48) [Mþ], 364 (12), 272
(100), 91 (83), 65(17).
3,3,6,6-Tetramethyl-9-(anthracen-9-yl)-1,2,3,4,5,6,7,8,9,10-
decahydroacridin-1,8-dione (4e). Yellow solid, M.P ¼ 296–
298ꢁC (KBr, cmꢀ1) Vmax: 3346, 3044, 2952, 1649, 1596, 1H
NMR (300 MHz; DMSO-d6): d ¼ 0.66 (6H, s, 2CH3), 0.97
(6H, s, 2CH3),1.73 (2H, d, J ¼ 16.3 Hz, 2CH), 2.05 (2H, d, J
¼ 16.3 Hz, 2CH), 2.33 (2H, d, J ¼ 16.9 Hz, 2CH), 2.51 (2H,
d, J ¼ 16.9 Hz, 2CH), 6.42 (1H, s, 1CH), 7.33 (2H, m, 2CH),
7.48 (2H, m, 2CH), 7.96 (2H, m, CH), 8.26 (1H, d, J ¼ 8.6
Hz, CH), 8.34 (1H, s, 1CH), 9.11 (1H, d, J ¼ 8.6 Hz, CH),
9.59 (1H, s, NH). 13C NMR (75 MHz, DMSO-d6): 26.28,
29.12, 30.02, 31.56, 40.38, 50.23, 112.72, 124.00, 124.73,
126.25, 131.19, 139.73, 148.89, 194.46, MS (EI): m/e ¼ 449
(24), 432 (4) [Mþ], 365 (2), 272 (71), 215 (36), 178 (100).
3,3,6,6-Tetramethyl-9-(naphthalen-2-yl)-1,2,3,4,5,6,7,8,9,10-
decahydroacridin-1,8-dione (4f). Yellow solid, M.P > 334ꢁC
(KBr, cmꢀ1) Vmax: 3291, 3173, 3044, 2952, 2854, 1647, 1H
NMR (300 MHz; DMSO-d6): d ¼ 0.84 (6H, s, 2CH3), 1.00
(6H, s, 2CH3), 1.96 (2H, d, J ¼ 16.1 Hz, 2CH), 2.18 (2H, d, J
¼ 16.1 Hz, 2CH), 2.35 (2H, d, J ¼ 17 Hz, 2CH), 2.48 (2H, d,
J ¼ 16.8 Hz, 2CH), 5.54 (1H, s, CH), 7.36–7.43 (3H, m,
3CH), 7.59 (1H, s, 1CH), 7.69–7.77 (3H, m, 3CH), 9.35 (1H,
s, NH). 13C NMR (75 MHz, DMSO-d6): 26.38, 29.13, 32.14,
33.28, 40.35, 50.24, 111.28, 125.06, 125.57, 125.70, 126.83,
127.09, 127.22, 127.54, 131.53, 132.72, 144.57, 149.46,
194.43 MS (EI): m/e ¼ 399 (24) [Mþ], 382 (6), 314 (3), 272
(100), 256 (5), 216 (6), 188 (8), 127 (12), 77 (5).
¨
ported material with Bronsted acid properties. The MCM-41
was synthesized according to the previously described method
using cetyltrimethylammonium bromide (CTMABr), as the tem-
plating agent [13]. The surfactant template was then removed
from the synthesized material by calcination at 540ꢁC for 6 h.
MCM-41 was modified using a 100-mL suction flask
equipped with a constant-pressure dropping funnel containing
chlorosulfonic acid (81.13 g and 0.7 mol) and a gas inlet tube
for conducting HCl gas over an adsorbing solution. Then, 60.0
g of MCM-41 was charged into it and chlorosulfonic acid was
added dropwise over a period of 30 min at room temperature.
HCl gas evolved from the reaction vessel immediately. After
completion of addition, the mixture was shaken for 30 min,
and the white solid (MCM-41-SO3H) was obtained (115.9 g).
General procedure for the synthesis of 1,8-dioxo-9-aryl
decahydroacridines. A mixture of aldehyde (1 mmol), dime-
done (2 mmol), ammonium acetate (3 mmol), MCM-41-SO3H
(0.005 g) were mixed and heated in a paraffin bath at 110ꢁC
for different periods of time (Table 4). After completion of the
reaction (monitored by TLC; petroleum ether and EtOAc, 1:2),
excess ammonium acetate was washed away by water. Subse-
quently, products were crystallized from ethanol.
The spectral data of some representative products. 3,3,
6,6-Tetramethyl-9-(2,3-dichlorophenyl)-1,2,3,4,5,6,7,8,9,10-deca-
hydroacridin-1,8-dione (4a). Yellow solid, M.P. >322ꢁC (KBr,
cmꢀ1) Vmax: 3286, 3178, 3049, 2957, 2859, 1647, 1H NMR
(300 MHz; DMSO-d6): d ¼ 0.84 (6H, s, 2CH3), 0.99 (6H, s,
2CH3), 1.92 (2H, d, J ¼ 16.0 Hz, 2CH), 0.14 (2H, d, J ¼ 16.1
Hz, 2CH), 2.28 (2H, d, J ¼ 17 Hz, 2CH), 2.45 (2H, d, J ¼ 17
Hz, 2CH), 5.14 (1H, s, 1CH), 7.13–7.31 (3H, m, CH), 9.37
(1H, s, NH),13C NMR (75 MHz, DMSO-d6): 26.35, 29.01,
31.95, 33.67, 40.16, 50.16, 110.87, 126.98, 127.56, 129.05,
130.54, 131.41, 147.18, 149.78, 194.17. MS (EI): m/e ¼ 417
(4) [Mþ], 382 (43), 272 (100), 256 (2), 216 (6), 188 (8), 160
(3), 144 (3), 109 (2), 83 (6), 77 (5), 55 (6).
3,3,6,6-Tetramethyl-9-(naphthalen-1-yl)-1,2,3,4,5,6,7,8,9,10-
decahydroacridin-1,8-dione (4g). Yellow solid, M.P. 305–
307ꢁC, (KBr, cmꢀ1) Vmax:3512, 3301, 3203, 3065, 2962, 2870,
1653, 1622, 1478 H NMR (300 MHz; CDCl3): d ¼ 0.81 (6H,
N-(4-(1,2,3,4,5,6,7,8,9,10-Decahydro-3,3,6,6-tetramethyl-1,8-
dioxoacridin-9yl)phenyl)acetamide (4b). Yellow solid, M.P.
341–342ꢁC, (KBr, cmꢀ1) Vmax: 3471, 3306, 3038, 2951, 1615,
1H NMR (300 MHz; CDCl3): d ¼ 0.85 (6H, s, 2CH3), 0.99
(6H, s, 2CH3), 1.99 (3H, s, CH3), 1.94–2.49 (8H, m, 4CH2),
4.74 (1H, s, CH), 7.04 (2H, d, J ¼ 8.48 Hz, 2CH), 7.31 (2H,
d, J ¼ 8.4 Hz, 2CH), 9.23(1H, s, NH). 13C NMR (75 MHz,
CDCl3): 23.82, 25.44, 29.07, 32.10, 32.2, 38.66, 39.22, 39.50,
39.78, 40.05, 50.25, 11.50, 118.52, 127.88, 136.72, 142.08,
149.11, 167.88, 194.34 MS (EI): m/e ¼ 406 (8) [Mþ], 405
(5), 377 (5), 272 (100), 102 (12), 43 (29).
3,3,6,6-Tetramethyl-9-(4-cyanophenyl)-1,2,3,4,5,6,7,8,9,10-
decahydroacridin-1,8-dione(4c). Yellow solid, M.P. 328–
330ꢁC , (KBr, cmꢀ1) Vmax:3327, 3234, 3080, 2957, 2233, 1642,
1H NMR (300 MHz; CDCl3): d ¼ 0.84 (6H, s, 2CH3), 0.99 (6H,
s, 2CH3), 1.98 (2H, d, J ¼ 16 Hz, 2CH), 2.17 (2H, d, J ¼ 16 Hz,
2CH), 2.33 (2H, d, J ¼ 17 Hz, 2CH), 2.45 (2H, d, J ¼ 17 Hz,
2CH), 4.85 (1H, s, CH), 7.33 (2H, d, J ¼ 8.2 Hz, 2CH), 7.63
(2H, d, J ¼ 18 Hz, 2CH), 9.40 (1H, s, NH). 13C NMR (75 MHz,
CDCl3): 26.44, 28.93, 32.08, 33.82, 38.66, 39.21, 39.77, 40.05,
1
S, 2CH3),1.00 (6H, s, 2CH3), 1.86 (2H, d, J ¼ 16.2 Hz, 2CH),
2.14 (2H, d, J ¼ 16.1 Hz, 2CH), 2.35 (2H, d, J ¼ 17.04 Hz,
2CH), 2.51 (2H, d, J ¼ 16.7 Hz, 2CH), 5.5 (1H, s, CH),7.2
(1H, d, J ¼ 8.2 Hz, 1CH), 7.4 (1H, d, J ¼ 7.3 Hz, 1CH), 7.5
(1H, d, J ¼ 7.6 Hz, 1CH),7.6 (1H, d, J ¼ 7.7 Hz, 1CH),7.8
(1H, d, J ¼ 8.0 Hz, 1CH), 8.7(1H, d, J ¼ 8.5 Hz, 1CH), 9.3
(1H, s, NH).13C NMR (75 MHz, DMSO-d6):18.55, 26.26,
29.15, 32.05, 50.18, 56.01, 113.16, 124.82, 125.34, 125.97,
126.12, 127.46, 132.76, 148.86, 194.47, MS (EI): m/e ¼ 399
(140), 382 (2), 314 (4), 272 (100), 127 (42), 77 (16), 41 (23).
3,3,6,6-Tetramethyl-9-(2-chlorophenyl)-1,2,3,4,5,6,7,8,9,10-
decahydroacridin-1,8-dione(4j). Yellow solid, M.P. 309–
310ꢁC (KBr, cmꢀ1) Vmax: 3286, 3198, 3055, 2957, 2859,1647,
1617 1H NMR (300 MHz; DMSO-d6): d ¼ 0.86 (6H, s,
2CH3), 0.89 (6H, s, 2CH3), 1.99 (2H, d, J ¼ 9.55 Hz, 2CH),
2.17 (2H, d, J ¼ 8.07 Hz, 2CH), 2.33 (2H, d, J ¼ 7.03 Hz,
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115
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