ZnFe2O4 nanoparticles as a robust and reusable magnetically catalyst in the four component synthesis of [(5-hydroxy-3-methyl-1H-pyrazol-4yl) (phenyl) methyl]propanedinitriles and substituted 6-amino-pyrano[2,3-c]pyrazoles

Article abstract of DOI:10.3184/174751915X14358475706316

A simple method has been developed for the synthesis of [(5-hydroxy-3-methyl-1H-pyrazol-4-yl)(phenyl)methyl]propanedinitriles and 6-amino-4-aryl-3-methyl-2,4-dihydro pyrano[2,3-c]pyrazole-5-carbonitrile derivatives through a one-pot four-component condens

Full text of DOI:10.3184/174751915X14358475706316

410 RESEARCH PAPER
VOL. 39 JULY, 410–413
JOURNAL OF CHEMICAL RESEARCH 2015
ZnFe O nanoparticles as a robust and reusable magnetically catalyst in the
2
4
four component synthesis of [(5-hydroxy-3-methyl-1H-pyrazol-4yl) (phenyl)
methyl]propanedinitriles and substituted 6-amino-pyrano[2,3-c]pyrazoles
Javad Safaei-Ghomi*, Hossein Shahbazi-Alavi and Elham Heidari-Baghbahadorani
Department of Organic Chemistry, Faculty of Chemistry, University of Kashan, Kashan, PO Box 87317-51167, Iran
A simple method has been developed for the synthesis of [(5-hydroxy-3-methyl-1H-pyrazol-4-yl)(phenyl)methyl]propanedinitriles and
6
-amino-4-aryl-3-methyl-2,4-dihydro pyrano[2,3-c]pyrazole-5-carbonitrile derivatives through a one-pot four-component condensation
reaction of aromatic aldehydes, malononitrile, ethyl acetoacetate and hydrazine hydrate using ZnFe O nanoparticles under solvent-free
2
4
conditions. This has the advantages of excellent yields, short reaction times, simple workup and environmentally benign.
Keywords: pyranopyrazoles, pyrazolpropanedinitriles, ZnFe O4 nanoparticles, one-pot condensation reaction, solvent-free conditions, robust
2
catalyst
The pyranopyrazole ring is one of the important heterocyclic
systems which show some pharmacological and biological
catalysts. Separation of magnetic nanoparticles is simple,
16
convenient, economical and environmentally benign. We
now report the synthesis of [(5-hydroxy-3-methyl-1H-pyrazol-
4-yl) (phenyl)methyl]propanedinitriles and 6-amino-4-aryl-
1
properties such as Molluscicidal, analgesic and anti-
2
3
inflammatory, Chk1 inhibitors activities. The development
of new, rapid and clean synthetic routes towards libraries
of such compounds is of value to both medicinal and
synthetic chemistsThe synthesis of pyranopyrazoles through
multicomponent reactions (MCRs) received attention owing
to their excellent synthetic efficiency, inherent atom economy,
3-methyl-2,4-dihydropyrano[2,3-c]
pyrazole-5-carbonitrile
derivatives by a one-pot four-component condensation reaction
of aromatic aldehydes, malononitrile, ethyl acetoacetate and
hydrazine hydrate catalysed by ZnFe O NPs (Scheme 1).
2
4
4
-6
Results and discussion
procedural simplicity, and environmental friendliness.
Substituted 6-aminopyrano[2,3-c]pyrazoles were first
In order to optimise the reaction conditions, the condensation
reaction of 4-nitrobenzaldehyde, malononitrile, hydrazine
hydrate and ethyl acetoacetate was selected as a model. We
studied the effects of the catalyst and solvent on the synthesis
synthesised by a reaction between 3-methyl-5-pyrazolone
7
with tetracyanoethylene. Various 2,4-dihydropyrano [2,3-c]
8
pyrazole-5-carbonitriles were synthesised using γ-alumina,
9
10
11
piperidine, imidazole, glycine, [(CH ) SO HMIM][HSO ],
as a catalyst. Although many methods for the synthesis of
of
6-amino-4-(4-nitrophenyl)-3-methyl-2,4-dihydropyrano
2
4
3
4
12
[2,3-c]pyrazole-5-carbonitrile (Scheme 2). A wide variety
pyrano[2,3-c]pyrazoles are known, some have drawbacks,
including long reaction times, difficult purification, high
catalyst loading and non-reusable catalyst, and may require
special conditions. Our method provides several advantages
including mild reaction condition, applicability to wide range of
substrates, easy purification, reusability of the catalyst and low
catalyst loading.
of catalysts including P O , ZnCl , CaO, CuO, ZrO , ZrOCl
2
5
2
2
2
and ZnFe O NPs were employed to test their efficacy for the
2
4
synthesis of pyranopyrazoles. Next, we optimised the amount
of ZnFe O NPs required; the optimum amount was found to
2
4
be 8 mol %. We examined the reaction in different solvents
including acetonitrile, ethanol, water and solvent-free. The best
results were obtained under solvent-free conditions. The results
are presented in Table 1. The generality of this four-component
reaction was studied under optimal conditions by varying the
structure of the aldehydes (Table 2).
Organic reactions under solvent free conditions have attracted
interest from chemists particularly from the viewpoints of
green chemistry. Green chemistry emphasises the development
of environmentally benign chemical processes. From this point
An important feature of this method is that both electron-
releasing and withdrawing groups give excellent yields. A
decrease in the temperature led to a decrease of cyclisation rate,
so under these conditions only compound 5 was produced.
The recoverability of the nano‑ZnFe O catalyst was
13,14
of view, solvent-free MCRs are appealing procedures.
Expansion of new catalytic transformations with simple
separation and recyclability of the catalyst is an essential task in
15
chemical synthesis. To overcome the separation problems of the
nano catalysts, magnetic materials have emerged as recoverable
2
4
examined for the synthesis of product 6f and it was found that
R
R
CHO
O
O
N
CN
R
CN
CN
ZnFe O NPs
2 4
+
+
NH2-NH2
+
N
N
O
CN
0
RT
N
80 C
OH
N
O
NH2
H
H
1
2
3
4
5
6 a-j
Scheme 1 Synthesis of pyranopyrazoles from aldehydes, malononitrile, ethyl acetoacetate, and hydrazine hydrate using ZnFe O nanoparticles.
2
4
*
Correspondent. E-mail: safaei@kashanu.ac.ir

JOURNAL OF CHEMICAL RESEARCH 2015 411
NO2
CHO
NO2
O
O
CN
CN
+
NH2
ZnFe O NPs
+
2 4
+
OEt
H N
2
CN
N
N
O
NH2
H
Scheme 2 The model reaction for the preparation of 6-amino-4-(4-nitrophenyl)-3-methyl-2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile 6f.
a
Table1 Optimisation of reaction condition using different catalysts
b
Entry
Solvent
EtOH
Conditions
Reflux
40° C
Reflux
40 °C
80 ° C
50 °C
40° C
Reflux
Reflux
80 °C
Catalyst/mol
P O (3)
Time/min
50
Yield/%
31
29
38
43
37
49
62
58
73
82
92
91
1
2
3
4
5
6
7
8
9
2
5
CH CN
ZnCl (3)
60
55
45
50
60
40
40
30
3
2
H2O
CaO (5)
CuO (5)
CH CN
3
H2O
EtOH
ZrO (4)
2
H PO (2)
3
4
CH CN
ZrOCl (5)
3
2
EtOH
EtOH
Solvent-free
Solvent-free
Solvent-free
ZrO (4)
2
ZnFe O NPs (8)
2
4
1
0
ZnFe O NPs (5)
15
15
15
2
4
1
1
80 °C
80 °C
ZnFe O NPs (8)
2
4
12
ZnFe O NPs (12)
2
4
a
4
-Nitrobenzaldehyde (1mmol), malononitrile (1mmol), ethyl acetoacetate (1mmol) hydrazine hydrate (1mmol) for synthesis 6-amino-4-(4-nitrophenyl)-3-methyl-2,4-dihydropyrano[2,3-c]
pyrazole-5-carbonitrile .
b
Isolated yield.
Table 2 Synthesis of [(5-hydroxy-3-methyl-1H-pyrazol-4-yl)(phenyl)methyl]propanedinitriles (5a,b) and 6-amino-4-aryl-3-methyl-2,4-
dihydropyrano[2,3-c]pyrazole-5-carbonitriles (6a–j)
b
ref
Entry
Aldehyde (R)
H
4-OMe
H
4-Me
2-Me
3-Me
2-OMe
4-NO2
4-Cl
Products
Time/min
9
Yield/℅
91
88
88
90
89
89
85
92
92
M.p./º C
18
1
2
3
4
5
6
7
8
9
5a
5b
6a
6b
6c
6d
6e
6f
256–258
18
12
15
14
15
17
19
15
14
207–208
244–246
206–208
8
8
209–211
212–214
215–217
8
251–253
234–236
8
6g
6h
6i
1
0
2-F
4-Br
15
14
90
91
163–165
8
11
178–180
210–212
8
1
2
4-OMe
6j
16
87
a
b
Hyrazine hydrate (1 mmol), ethyl acetooacetate (1 mmol), malononitrile (1mmol), aldehydes (1 mmol)with ZnFe O nanoparticles.
Isolated yield.
2
4
product yields decreased to a small extent on each reuse (run 1,
2%; run 2, 91%; run 3, 91%; run 4, 90%; run 5, 90%). In the
recycling procedure of ZnFe O NPs, after completion of the
reaction, 5 mL ethanol was added and magnet was introduced
into the mixture in the form of a magnetic stirrer bar and
catalyst was separated magnetically. It is important to note that
the catalyst could be recovered magnetically and washed with
acetone to remove the residual product.
1H-pyrazol-4-yl) (phenyl) methyl] propanedinitrile derivatives
were formed. Mild reaction conditions, operational simplicity,
the use of green catalyst, no organic solvent and high isolated
yields of pure products are significant advantages of the method
described here.
9
2
4
Experimental
All organic materials were purchased commercially from Sigma-
Aldrich and Merck and were used without further purification. All
melting points were uncorrected and were determined in a capillary
tube on a Boetius melting point microscope or on Electro thermal
9200. The elemental analyses (C, H, N) were obtained from a Carlo
ERBA Model EA 1108 analyser. FTIR spectra were recorded with KBr
pellets using a Magna-IR, spectrometer 550 Nicolet. NMR spectra
In conclusion, it was found that under the optimal conditions
the reaction between malononitrile, hydrazine hydrate, ethyl
acetoacetate and aromatic aldehydes in the presence of 8 mol %
of ZnFe O at 80 °C leads to pyrano[2,3-c]pyrazoles selectively
2
4
in excellent yields. A decrease in the temperature led to
decrease of cyclisation rate, so that only [(5-hydroxy-3-methyl-

412 JOURNAL OF CHEMICAL RESEARCH 2015
were recorded on a Bruker 400 MHz spectrometer with DMSO as
solvent and TMS as an internal standard. Powder XRD was carried
out on a Philips diffractometer of X’pert Company. Microscopic
morphology of the products was visualised by SEM (MIRA 3
TESCAN).
C H N O: C, 66.65; H, 4.79; N, 22.21; found: C, 66.60, H, 4.83, N,
14 12 4
22.26%.
6-Amino-2,4-dihydro-3-methyl-4-p-tolylpyrano[2,3-c]pyrazole-
8
5-carbonitrile (6b): M.p. 208–210 °C, (lit. 206–208); IR (KBr):
-1
1
νmax 3405, 3315, 3190, 2191, 1644, 1601 cm ; H NMR (400 MHz,
DMSO-d ): 1.76 (s, CH , 3H), 2.25 (s, CH , 3H), 4.52 (s, 1H), 6.85-
6
3
3
Synthesis of ZnFe O nanoparticles
2
4
13
7
.11 (m, 6H), 12.08(1H, NH) ppm; C NMR (100 MHz, DMSO-d ): δ
10.25, 21.23, 36.69, 57.65, 99.14, 121.24, 127.19, 127.91, 128.89, 136.03,
6
ZnFe O nanoparticle was prepared according to the procedure
2
4
17
reported in the literature. Iron (III) chloride hexahydrate
FeCl .6H O), zinc (II) chloride (ZnCl ), sodium hydroxide (NaOH)
1
44.89, 155.21, 161.31 ppm. Anal. calcd for C H N O: C, 67.65; H,
15 14 4
(
3
2
2
5.30; N, 21.04; found: C, 67.71; H, 5.21; N, 20.98%.
-Amino-2,4-dihydro-3-methyl-4-o-tolylpyrano[2,3-c]pyrazole-
-carbonitrile (6c): M.p. 209-211 °C, IR (KBr): ν 3399, 3311, 3168,
and acetone were analytical grade. A mixed aqueous solution was
prepared by dissolving the required weights of iron and zinc chloride
with the molar ratio of Fe to Zn as 2:1, in distilled water (100 mL). An
aqueous solution of 1.5 M NaOH (50 mL) was used as the precipitating
agent. Metal chloride and NaOH solutions were added dropwise
from two separate burettes into a reaction vessel containing 100 mL
of distilled water for obtaining uniform particle size distribution.
The reaction vessel was heated up to the desired temperature under
magnetic stirring. The resultant precipitates were collected and
centrifuged at 6000 rpm and then washed with distilled water and
acetone for several times and finally dried in air.
6
5
max
-1
1
2925, 2190, 1649, 1468 cm ; H NMR (400 MHz, DMSO-d ): 1.65 (s,
6
CH , 3H), 2.24 (s, CH , 3H), 4.81 (s, 1H), 6.81–7.09 (m, 6H), 12.05
3
3
13
(
5
1H, NH) ppm; C NMR (100 MHz, DMSO-d ): δ 10.21, 21.22, 36.52,
7.65, 99.14, 121.24, 127.19, 127.31,127.95, 128.83, 129.22, 136.02,
6
1
44.85, 155.20, 161.33 ppm. Anal. calcd for C H N O: C, 67.65; H,
15
14
4
5
.30; N, 21.04; found: C, 67.73; H, 5.23; N, 20.96%.
-Amino-4-(3-methylphenyl)-3-methyl-2,4-dihydropyrano[2,3-c]
pyrazole-5-carbonitrile (6d): M.p. 212–214 °C, IR (KBr): ν 3470,
6
max
-1
1
3
307, 3181, 2923, 2189, 1639 cm , H NMR (400 MHz, DMSO-d ): δ
6
1
1
3
.79 (s, CH , 3H), 2.25 (s, CH , 3H), 4.53 (s, 1H), 6.87-7.25 (m, 6H),
Synthesis of [(5-hydroxy-3-methyl-1H-pyrazol-4-yl)(phenyl)methyl]
propanedinitrile derivatives (5a,b); general procedure
3
3
13
2.09 (1H, NH) ppm C NMR (100 MHz, DMSO-d ): δ 10.25, 21.54,
6
6.61, 57.67, 98.15, 121.35, 125.16, 127.93, 128.36, 129.1, 136.06,
Hydrazine monohydrate (1 mmol) and ethyl acetoacetate (1 mmol)
were mixed, then, aromatic aldehydes (1 mmol), malononitrile (1
mmol) and ZnFe O NPs (8 mol%) as catalyst were added and stirred
1
37.98, 144.99, 155.27, 161.33. Anal. calcd for C H N O: C, 67.65; H,
15 14 4
5
.30; N, 21.04; found: C 67.72; H, 5.25; N, 20.98%.
-Amino-2,4-dihydro-4-(2-methoxyphenyl)-3-methylpyrano
2,3-c]pyrazole-5-carbonitrile (6e): M.p. 215–217 °C, IR (KBr):
2
4
6
at room temperature under solvent-free conditions for the specific time.
After completion of the reaction, ethanol (5 mL) was added and magnet
was introduced into the mixture in the form of a magnetic stirrer bar
and catalyst was separated magnetically. The precipitate was filtered
off and washed with a mixture of ethyl acetate/hexane (20:80).
[
-1
1
νmax 3376, 3163, 2928, 2193, 1654, 1604, 1488 cm , H NMR (400
MHz, DMSO-d ): δ 1.77 (s, CH , 3H), 3.77 (s, OCH , 3H), 4.95 (s,
6
3
3
13
1
H), 6.79–7.18 (m, 6H), 12.00 (1H, NH) ppm; C NMR (100 MHz,
DMSO-d ): δ 10.23, 36.55, 55.95, 57.65, 99.18, 121.28, 127.19,
6
Synthesis of 6-amino-4-aryl-3-methyl-2,4-dihydro pyrano[2,3-c]
pyrazole-5-carbonitrile derivatives (6a–j); general procedure
127.36,127.97, 128.83, 129.25, 136.01, 144.82, 155.22, 161.34 ppm.
Anal. calcd for C H N O : C, 63.82; H, 5.00; N, 19.85; found: C,
15
14
4
2
Hydrazine monohydrate (1 mmol) and ethyl acetoacetate(1 mmol)
were mixed and then the aromatic aldehyde (1 mmol), malononitrile
63.78; H, 5.09; N, 19.72%.
6-Amino-2,4-dihydro-3-methyl-4-(4-nitrophenyl)pyrano[2,3-c]
pyrazole-5-carbonitrile (6f): M.p. 250–252 °C, (lit. 251–253) IR
8
(
1 mmol) and ZnFe O NPs (8 mol%) as the catalyst were added. The
2
4
-1
1
mixture was stirred at 80° C under solvent-free conditions for the
specific time (Table 1). After completion of the reaction, ethanol (5
mL) was added. A magnet in the form of a magnetic stirrer bar was
added and the catalyst was separated magnetically. The precipitated
(KBr): νmax 3425, 3231, 2925, 2192, 1644, 1403 cm , H NMR (400
MHz, DMSO-d ): δ 1.78 (s, CH , 3H), 4.96 (s, 1H), 7.07 (NH , 2H),
6
3
2
7.44–7.46 (d, J= 8 Hz, 2H), 8.25–8.27 (d, J= 8 Hz, 2H), 12.14 (1H,
13
NH) ppm; C NMR (100 MHz, DMSO-d ): δ 10.20, 36.36, 56.39,
6
solid was filtered and washed with a mixture of ethyl acetate/hexane
97.01, 120.96, 124.35, 129.30, 136.37, 146.84, 152.56, 155.13, 161.61
1
(
20:80). The purity of obtained products was assessed by H NMR
ppm. Anal. calcd for C H N O : C, 56.56; H, 3.73; N, 23.56; found: C,
14
11
5
3
spectroscopy.
(5-Hydroxy-3-methyl-1H-pyrazol-4-yl) (phenyl)methyl] propane-
56.48; H, 3.65; N, 23.61%.
6-Amino-4-(4-chlorophenyl)-3-methyl-2,4-dihydropyrano[2,3-c]
pyrazole-5-carbonitrile (6g): M.p. 228–230 °C, (lit. 234–236); IR
[
18
8
dinitrile (5a): M.p. 254–256 °C, (lit. 256-258); IR (KBr): ν 3383,
max
-1
1
-1
1
3
4
(
300, 2207 cm ; H NMR (400 MHz, DMSO-d ): δ 2.09 (3H, s, CH ),
.65 (1H, d, J=11.2 Hz, CH), 5.52 (1H, d, J= 11.2 Hz, CH),7.20-7.55
m, 5H, Ar), 10.5-11.5 (br s, 2H, NH, OH) ppm; C NMR (100 MHz,
(KBr): νmax 3408, 3369, 3307, 2188, 1643 cm , H NMR (400 MHz,
DMSO-d ): δ 1.77 (3H, s, CH ), 4.62 (s, 1H), 6.94 (2H, s, NH ),
6
3
6
3
2
13
7.17–7.19 (2H, d, J= 8Hz), 7.35–7.37 (2H, d, J= 8Hz) 12.09 (1H, NH)
13
DMSO-d ): δ 9.6, 18.4, 27.6, 99.8, 113.9 (2 C), 114.1, 128.8 (2 C), 131.6,
ppm; C NMR (100 MHz, DMSO-d ): δ 10.2, 36.3, 56.7, 99.0, 120.6,
6
6
1
37.7, 158.5, 159.0. Anal. calcd for C H N O: C, 66.65; H, 4.79; N,
128.4, 129.3, 131.2, 135.6, 143.4, 154.7,160.9 ppm. Anal. calcd for
14
12
4
2
2.21; found: C 66.60; H, 4.70; N, 22.19%.
(5-Hydroxy-3-methyl-1H-pyrazol-4-yl) (4-methoxyphenyl)methyl]
C H ClN O: C, 58.65; H, 3.87; N, 19.54; found: C 58.60; H, 3.80; N,
19.48%.
6-Amino-4-(2-fluorophenyl)-2,4-dihydro-3-methylpyrano[2,3-
14
11
4
[
18
malononitrile (5b): M.p. 207–209 °C, (lit. 207–208); IR (KBr):
-1
1
νmax 3481, 3354, 3255, 2950, 2192, 1641 cm ; H NMR (400 MHz,
DMSO-d ): δ 2.08 (s, 3H, CH ), 3.74 (s, 3H, OCH ), 4.59 (d, J =
c]pyrazole-5-carbonitrile (6h): M.p. 163–165°C, IR (KBr): ν 3366,
max
-1 1
3312, 2186, 1641 cm , H NMR (400 MHz, DMSO-d ): δ 1.78 (3H, s,
CH ), 4.84 (s, 1H), 6.96 (2H, s, NH ), 7.14–7.16 (m, 3H), 7.26–7.28 (m,
1H), 12.13 (1H, NH) ppm; C NMR (100 MHz, DMSO-d ): δ 9.6, 36.0,
56.5, 98.5, 120.6, 121.3, 121.4, 128.4, 129.3, 129.5, 131.3,135.6, 143.3,
6
3
3
6
11.4 Hz, 1H, CH), 5.45 (d, J = 11.4 Hz, 1H, CH), 6.93 (d, J = 8.5 Hz,
3
2
13
2
H, Ar), 7.42 (d, J = 8.5 Hz, 2H, Ar), 10.86 (br s, 2H, NH and OH);
6
13
C NMR (100 MHz, DMSO-d ): δ 9.7, 18.5, 27.7, 55.1, 98.9, 113.9
6
(
2 C), 114.1, 128.9 (2 C), 131.8, 137.8, 158.6, 159.0; Anal calcd for
154.8,161.1 ppm. Anal. calcd for C H FN O: C, 62.22; H, 4.10; N,
14
11
4
C H N O : C, 63.82; H, 5.00; N, 19.85; found: C, 63.71; H, 5.09; N,
20.73; found: C, 62.15; H, 4.16; N, 20.67%.
15
14
4
2
1
9.78%.
6-Amino-4-(4-bromophenyl)-2,4-dihydro-3-methylpyrano[2,3-c]
8
6
-Amino-3-methyl-4-phenyl-2,4-dihydro pyrano[2,3-c]-pyrazole-
pyrazole-5-carbonitrile (6i): M.p. 179–181 °C, (lit. 178–180); IR
8
-1
1
5
3
3
-carbonitrile (6a): M.p. 244–246°C, (lit. 244–246); IR (KBr): ν
(KBr): νmax 3470, 3234, 3117, 2192, 1645 cm , H NMR (400 MHz,
DMSO-d ): δ 1.77 (3H, s, CH ), 4.61 (s, 1H), 6.92 (2H, s, NH ),
max
-
1 1
371, 3248, 2192 cm ; H NMR (400 MHz, DMSO-d ): 1.76 (s, CH ,
H), 4.57 (s, 1H), 6.89–7.30 (m, 7H), 12.09 (1H, NH) ppm; C NMR
6
3
6
3
2
13
7.16–7.18 (2H, d, J= 8Hz), 7.34-7.36 (2H, d, J= 8Hz), 12.12 (1H, NH)
13
(
1
100 MHz, DMSO-d ): δ 10.17, 36.67, 57.64, 99.14, 121.24, 127.19,
ppm; C NMR (100 MHz, DMSO-d ): δ 10.3, 36.6, 56.8, 99.1, 120.7,
6
6
27.91, 128.89, 136.03, 144.89, 155.21, 161.31 ppm. Anal. calcd for
128.5, 129.4, 131.3, 135.6, 143.6, 154.7,161.1 ppm. Anal. calcd for

JOURNAL OF CHEMICAL RESEARCH 2015 413
C H BrN O: C, 50.77; H, 3.35; N, 16.92; found: C, 50.65; H, 3.26; N,
2
3
S.C. Kuo, L.J. Huang and H. Nakamura, J. Med. Chem., 1984, 27, 539.
N. Foloppe, L.M. Fisher, R. Howes, A. Potter, A.G.S. Robertson and A.E.
Surgenor, Bioorg. Med. Chem., 2006, 14, 4792.
J. Safaei-Ghomi, M. R. Saberi‑Moghadam, H. Shahbazi‑Alavi and M.
Asgari‑Kheirabadi, J. Chem. Res., 2014, 38, 583.
B. Jiang, T. Rajale, W. Wever, S.J. Tu and G. Li, Chem. Asian J., 2010, 5,
2318.
F. Yu, R. Huang, H. Ni, J. Fan, S. Yan and J. Lin. Green Chem., 2013, 15,
453.
H. Junek and H. Aigner, Chem. Ber., 1973, 106, 914.
H. Mecadon, M.R. Rohman, M. Rajbangshi and B. Myrboh, Tetrahedron
Lett., 2011, 52, 2523.
14
11
4
16.88%.
6
-Amino-2,4-dihydro-4-(4-methoxyphenyl)-3-methylpyrano[2,3-c]
4
5
6
8
pyrazole-5-carbonitrile (6j): M.p. 208–210 °C, (lit. 210–212);
IR (KBr): νmax 3420, 3249, 2899, 2201, 1644 cm , H NMR (400
-
1
1
MHz, DMSO-d ): δ 1.75 (3H, s, CH ), 3.70 (3H, s, OCH ), 4.51 (s,
6
3
3
13
1
H), 6.83–7.06 (m, 6H), 12.07 (1H, NH) ppm; C NMR (100 MHz,
DMSO-d ): δ 10.21, 36.52, 55.90, 57.62, 99.09, 121.28, 127.19, 127.97,
6
7
8
1
28.82, 136.01, 144.72, 155.16, 161.24 ppm. Anal. calcd for C H N O :
15 14 4 2
C, 63.82; H, 5.00; N, 19.85; found: C, 63.91; H, 5.10; N, 19.74%.
9
10
G. Vasuki and K. Kumaravel, Tetrahedron Lett., 2008, 49, 5636.
A. Siddekha, A. Nizam and M.A. Pasha, Spectrochim. Acta Part A, 2011,
81, 431.
Electronic Supplementary Information
The spectral data of products are described in the ESI available
through: stl.publisher.ingentaconnect.com/content/stl/jcr/supp
11 M.B. Madhusudana Reddy, V.P. Jayashankara and M.A. Pasha, Synthetic
Commun., 2010, 40, 2930.
‑
data.
12
J. Ebrahimi, A. Mohammadi, V. Pakjoo, E. Bahramzade and A. Habibi. J.
Chem. Sci., 2012, 124, 1013.
M.A.P. Martins, C.P. Frizzo, D.N. Moreira, L. Buriol and P. Machado,
Chem. Rev., 2009, 109, 4140.
The authors are grateful to University of Kashan for supporting
this work through grant no. 463562/VI.
13
14
R. Kumar, K. Raghuvanshi, R.K. Verma and M.S. Singh, Tetrahedron
Lett., 2010, 51, 5933.
Received 3 March 2015; accepted 24 June 2015
Paper 1503280 doi: 10.3184/174751915X14358475706316
Published online: 9 July 2015
1
5
J. Safaei-Ghomi, E. Heidari-Baghbahadorani and H. Shahbazi-Alavi.
Monatsh Chem., 2015, 146, 181.
C.W. Lim and I.S. Lee, Nano Today, 2010, 5, 412.
R. Raeisi Shahraki, M. Ebrahimi, S.A. Seyyed Ebrahimi and S.M.
Masoudpanah, J. Magnet. Magnetic Mater., 2012, 324, 3762.
1
6
17
References
1
F. M. Abdelrazek, P. Metz, N. H. Metwally and S. F. El-Mahrouky, Arch.
Pharm. Chem. Life Sci., 2006, 339, 456–460.
18 M.N. Elinson, R. F. Nasybullin and G. I. Nikishin, C. r. Chim., 2013, 16,
789-794.