Efficient NaOH-catalyzed reaction of aromatic aldehyde, cyclic ketones, and malononitrile under solvent-free conditions using a grinding method

Article abstract of DOI:10.1080/00397910802164724

An efficient and facile synthesis of 2,6-dicyanoanilines via a one-pot reaction of aromatic aldehydes, malononitrile, and cyclic ketones in the presence of NaOH under solvent-free conditions using a grinding method has been developed. Compared with the classical reaction conditions, the new synthetic method has the advantages of excellent yields, shorter reaction times, and mild reaction conditions. Copyright Taylor & Francis Group, LLC.

Full text of DOI:10.1080/00397910802164724

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Efficient NaOH-Catalyzed
Reaction of Aromatic
Aldehyde, Cyclic Ketones,
and Malononitrile Under
Solvent-Free Conditions Using a
Grinding Method
Liangce Rong a b , Hongxia Han a , Hong Jiang b &
Shujiang Tu a b
a College of Chemistry and Chemical Engineering,
Xuzhou Normal University, Xuzhou, Jiangsu, P.R.
China
b The Key Laboratory of Biotechnology for Medicinal
Plants, Xuzhou, Jiangsu, P.R. China
Published online: 29 Sep 2008.
To cite this article: Liangce Rong , Hongxia Han , Hong Jiang & Shujiang Tu (2008):
Efficient NaOH-Catalyzed Reaction of Aromatic Aldehyde, Cyclic Ketones, and
Malononitrile Under Solvent-Free Conditions Using a Grinding Method, Synthetic
Communications: An International Journal for Rapid Communication of Synthetic
Organic Chemistry, 38:20, 3530-3542
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Synthetic Communications1, 38: 3530–3542, 2008
Copyright # Taylor & Francis Group, LLC
ISSN: 0039-7911 print=1532-2432 online
DOI: 10.1080/00397910802164724
Efficient NaOH-Catalyzed Reaction of Aromatic
Aldehyde, Cyclic Ketones, and Malononitrile
Under Solvent-Free Conditions Using a
Grinding Method
Liangce Rong,1,2 Hongxia Han,1 Hong Jiang,2 and Shujiang Tu1,2
1College of Chemistry and Chemical Engineering, Xuzhou Normal
University, Xuzhou, Jiangsu, P.R. China
2The Key Laboratory of Biotechnology for Medicinal Plants, Xuzhou,
Jiangsu, P.R. China
Abstract: An efficient and facile synthesis of 2,6-dicyanoanilines via a one-pot reac-
tion of aromatic aldehydes, malononitrile, and cyclic ketones in the presence of
NaOH under solvent-free conditions using a grinding method has been developed.
Compared with the classical reaction conditions, the new synthetic method has the
advantages of excellent yields, shorter reaction times, and mild reaction conditions.
Keywords: 2,6-Dicyanoanilines, green chemistry, grinding, solvent free, synthesis
Developing green organic syntheses is very important now. Organic
synthesis in the absence of solvent is a powerful tool for the generation
of structurally diverse molecules, and it is attractive because of reduced
pollution, low costs, mild reaction conditions, easy separation, and easy
purification. Therefore, in recent years, solvent-free organic reactions
have attracted great interest.[1] Many reactions proceed efficiently with-
out solvent. Indeed, in many cases, the solvent-free organic reaction
occurs more efficiently and more selectively than does its solution coun-
terpart, because molecules in a solid state are arranged tightly and regu-
larly. Some solvent-free reactions can be carried out just by grinding.[2]
Received February 2, 2008.
Address correspondence to Liangce Rong, College of Chemistry and Chemical
Engineering, Xuzhou Normal University, Xuzhou, Jiangsu-221116, China.
E-mail: lcrong2005@yahoo.com
3530

Synthesis of 2,6-dicyanoanilines
3531
Currently, solvent-free organic reactions have attracted much interest not
only for laboratory synthesis but also in the chemical industry.
2,6-Dicyanoanilines are typical acceptor–donor–acceptor (A-D-A) sys-
tems comprising one electron donor and two electron acceptors,[3,4] which
are very important compounds for their optical properties[5] and are the
basis for artificial photosynthetic systems,[6,7] materials presenting semicon-
ducting or nonlinear optical properties,[8] and molecular electronic devices.[9]
The synthesis of these compounds has attracted attention of chemists.
Though several methods for their synthesis have been reported,[10–13] many
of these procedures are not fully satisfactory with regard to operational sim-
plicity, cost of the reagent, and isolated yield; moreover, the majority of
those synthetic methods were carried out in nocuous organic solvent.
In continuation of our current studies on the application of solvent-
free conditions for the synthesis of organic compounds,[14–17] herein,
we report a practical and simple method to prepare polysubstituted
2,6-dicyanoaniline derivatives by grinding the starting materials under
dry conditions at room temperatures.
In an initial endeavor, 4-methylbenzaldehyde and cyclohexanone were
chosen to react with malononitrile as a model reaction in the presence of
different catalysts. We found when weak bases (K2CO3, Al2O3) or acidic
catalysts [H2SO4, B(OH)3] were used, the reaction could not be carried
out. However, when a strong base, such as NaOH was used, the reacion
could be carried out smoothly. The other stronger base, KOH, also could
promote the reaction, but it did not improve the yield more than NaOH
Table 1. Synthesis of 3a under solvent-free conditions in the presence of different
catalystsa
Entry
Amount (g)
Catalyst
Yieldb (%)
1
2
3
4
5
6
7
8
9
1
1
1
2
2
3
2
0.2
0.2
ZnCl2
0
0
0
0
0
B(OH)3
H2SO4
Na2CO3
K2CO3
c
Al2O3
0
Ba(OH)2
NaOH
KOH
30
63
60
aReagents and conditions: 4-methylbenzaldehyde 1 (2 mmol), malononitrile 2
(5 mmol), cyclohexanone 3 (2 mmol), and NaOH (0.2 g).
bIsolated yields.
cBasic.

3532
L. Rong et al.
Table 2. Optimizing the reaction conditionsa
Entry
Amount (g)
Time (min)
Yieldb (%)
1
2
3
4
0.1
0.2
0.3
0.4
10
3
5
40
63
50
48
5
aReagents and conditions: 4-methylbenzaldehyde 1 (2 mmol), malononitrile 2
(5 mmol).
bIsolated yields.
did. The results are listed in Table 1. Among these catalysts, NaOH was the
most efficient catalyst of choice in terms of yields and cost.
With this optimistic result in hand, we further investigated the best
reaction conditions. We investigated the reaction outcome using different
amounts of NaOH. To increase the quantity of NaOH from 0.1 to 0.4 g,
the reaction gave different outcomes, resulting in the isolation of 3a in
about 40, 63, 50, and 48% yields, respectively. Higher loading of the cat-
alyst did not improve the yields of the reaction. Perhaps more NaOH
could turn the reagents into solid more quickly, which hindered the reac-
tion from completion. The results of the reaction are listed in Table 2. As
shown in Table 2, the best amount of NaOH was 0.2 g.
Using this condition, a series of 2,6-dicyanoaniline derivatives was
synthesized from aromatic aldehyde, malononitrile, and cyclohexanone
or cyclopentanone (Scheme 1). The results are summarized in Table 3.
From Table 3, we find that the aldehydes bearing either electron-with
drawing or electron-donating groups perform well in this reaction. There-
fore, we concluded that the electronic nature of the substituents has no
significant effect on this reaction.
Scheme 1. The reactions of aromatic aldehyde, cyclic ketones, and malonitrile
under solvent-free conditions.

Synthesis of 2,6-dicyanoanilines
3533
Table 3. Synthetic results of compounds 4
Entry
Ar
n
Time (min)
Product
Yield (%)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
4-CH3C6H4
3,4-Cl2C6H3
4-CH3OC6H4
2-ClC6H4
2,4-Cl2C6H3
3,4-(CH3)2C6H3
3,4-(CH3O)2C6H3
4-FC6H4
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
3
2
2
2
2
3
3
2
2
2
2
2
2
2
2
2
4a
4b
4c
4d
4e
4f
63
66
71
68
67
60
58
73
71
72
70
70
72
68
63
65
4g
4h
4i
4-CH3C6H4
2-ClC6H4
4-ClC6H4
4j
4k
4l
3-ClC6H4
2,4-Cl2C6H3
3,4-Cl2C6H3
3,4-(CH3)2C6H3
4-CH3OC6H4
4m
4n
4o
4p
According to the product, the possible mechanism could be explained
by Scheme 2. To our delight, we obtained the intermediate 5 of product 4d.
X-ray diffraction analysis of the intermediate 5 confirmed our conjecture.
The structures of 4 were characterized by 1H NMR, IR, and elemen-
tal analysis, and the structures of 4a and the intermediate 5 were
Figure 1. Structure of compound 4a.

3534
L. Rong et al.
Figure 2. Structure of compound 5.
Scheme 2. Mechanisms of the reaction.

Synthesis of 2,6-dicyanoanilines
3535
additionally confirmed by X-ray diffraction analysis. The crystal struc-
tures of 4a and 5 are shown in Figs. 1 and 2, respectively.
In conclusion, we have successfully developed an efficient and facile
method to prepare a variety of polysubstituted 2,6-dicyanoaniline deriva-
tives via the one-pot reaction of different aromatic aldehydes, cyclic
ketones, and malononitrile under solvent-free conditions. We found that
NaOH was an excellent catalyst, because the reaction completed within
2–3 min. The important intermediate 5 was obtained successfully to con-
firm the presented mechanism. Because no toxic organic solvent was used,
this new protocol has the advantages of good yields, lower cost, reduced
environmental impact, and convenient procedure.
EXPERIMENTAL
General Procedure
Melting points were uncorrected. IR spectra were recorded on a Tensor 27
spectrometer in KBr. 1H NMR spectra were obtained in DMSO-d6 solution
with Me4Si as internal standard using a Bruker-400 spectrometer. Elemental
analyses were carried out using a Perkin-Elmer 240 II analyzer. X-ray dif-
fractions were recorded on a Siemens P4 or Simart-1000 diffractometer.
General Procedure for the Syntheses of 2,6-Dicyanoaniline Derivatives
The general procedure is represented as follows: aromatic aldehyde 1
(2 mmol), malononitrile 2 (5 mmol), ketone 3 (2 mmol), and NaOH
(0.2 g) were added to a mortar. The mixture was ground with a pestle
at room temperature. The reaction was completed within 2–3 min, and
the reaction mixture was poured into water. The product was filtered,
dried, and recrystallized from 95% ethanol.
Data
2-Amino-5,6,7,8-tetrahydro-4-p-tolylnaphthalene-1,3-dicarbonitrile (4a)
Mp: 189–191ꢀC. IR (KBr) v: 3443, 3357, 3250, 2958, 2873, 2220, 2210,
1648, 1566, 1518, 1458, 1436, 1318, 1269, 1171, 1021, 850, 816,
.
737 cmꢁ1 1H NMR (400 MHz, DMSO-d6) (d, ppm): 1.55 (2H, t,
J ¼ 5.6 Hz, CH2), 1.71 (2H, t, J ¼ 5.6 Hz, CH2), 2.16 (2H, t, J ¼ 6.0 Hz,
CH2), 2.38 (3H, s, CH3), 2.84 (2H, t, J ¼ 6.0 Hz, CH2), 6.43 (2H, s,
NH2), 7.15 (2H, d, J ¼ 8.0 Hz, ArH), 7.31 (2H, d, J ¼ 8.0 Hz, ArH). Anal.

3536
L. Rong et al.
calcd. for C19H17N3: C, 79.41; H, 5.96; N, 14.62. Found: C, 79.49; H,
5.93; N, 14.69.
2-Amino-4-(3,4-dichlorophenyl)-5,6,7,8-tetrahydronaphthalene-1,3-
dicarbonitrile (4b)
Mp: 229–230 ꢀC. IR (KBr) v: 3415, 3345, 3249, 2939, 2864, 2216, 1655,
1563, 1477, 1460, 1327, 1281, 1269, 1170, 1128, 1032, 888, 824, 816,
.
737 cmꢁ1 1H NMR (400 MHz, DMSO-d6) (d, ppm): 1.59 (2H, t,
J ¼ 6.4 Hz, CH2), 1.72 (2H, t, J ¼ 6.4 Hz, CH2), 2.17 (2H, t, J ¼ 6.0 Hz,
CH2), 2.86 (2H, t, J ¼ 6.0 Hz, CH2), 6.51 (2H, s, NH2), 7.31–7.34 (1H,
dd, J ¼ 2.0 Hz, J ¼ 2.0 Hz, ArH), 7.67 (1H, d, J ¼ 2.0 Hz, ArH), 7.78
(1H, d, J ¼ 8.4 Hz, ArH). Anal. calcd. for C18H13Cl2N3: C, 63.17; H,
3.83; N, 12.28. Found: C, 63.25; H, 3.75; N, 12.39.
2-Amino-4-(4-methoxyphenyl)-5,6,7,8-tetrahydronaphthalene-1,3-
dicarbonitrile (4c)
Mp: 192–194 ꢀC. IR (KBr) v: 3417, 3352, 2934, 2838, 2214, 1654, 1608, 1559,
1
1516, 1455, 1420, 1293, 1279, 1255, 1175, 1030, 824, 804cmꢁ1; H NMR
(400MHz, DMSO-d6) (d, ppm): 1.56 (2H, t, J¼ 6.0 Hz, CH2), 1.72 (2H, t,
J¼ 6.0 Hz, CH2), 2.19 (2H, t, J ¼ 6.4Hz, CH2), 2.84 (2H, t, J ¼ 6.4 Hz,
CH2), 3.82 (3H, s, OCH3), 6.40 (2H, s, NH2), 7.05 (2H, d, J ¼ 8.4 Hz,
ArH), 7.21 (2H, d, J ¼ 8.8 Hz, ArH). Anal. calcd. for C19H17N3O: C,
75.23; H, 5.65; N, 13.85. Found: C, 75.16; H, 5.76; N, 13.79.
2-Amino-4-(2-chlorophenyl)-5,6,7,8-tetrahydronaphthalene-1,3-
dicarbonitrile (4d)
Mp: 201–203 ꢀC. IR (KBr) v: 3413, 3345, 3249, 2936, 2863, 2216, 1655, 1562,
1461, 1406, 1282, 1255, 1171, 1090, 1078, 880, 807, 788, 731, 717 cmꢁ1. 1H
NMR (400 MHz, DMSO-d6) (d, ppm): 1.59 (2H, t, J ¼ 6.4 Hz, CH2), 1.69
(2H, t, J ¼ 6.4 Hz, CH2), 2.16 (2H, t, J ¼ 6.0 Hz, CH2), 2.85 (2H, t,
J¼ 6.0 Hz, CH2), 6.51 (2H, s, NH2), 7.25?7.27 (1H, m, ArH), 7.42 (1H, d,
J¼ 0.8 Hz, ArH), 7.54 (2H, d, J ¼ 8.0 Hz, ArH). Anal. calcd. for
C18H14ClN3: C, 70.24; H, 4.58; N, 13.65. Found: C, 70.16; H, 4.64; N, 13.77.
2-Amino-4-(2,4-dichlorophenyl)-5,6,7,8-tetrahydronaphthalene-1,3-
dicarbonitrile (4e)
ꢀ
Mp: 185–187 C. IR (KBr) v: 3451, 3348, 3245, 2952, 2863, 2226, 2213,
1645, 1589, 1563, 1481, 1458, 1435, 1381, 1276, 1170, 1104, 1056, 885,

Synthesis of 2,6-dicyanoanilines
3537
1
818, 752 cmꢁ1. H NMR (400 MHz, DMSO-d6) (d, ppm): 1.59 (2H, t,
J ¼ 6.0 Hz, CH2), 1.72 (2H, t, J ¼ 6.0 Hz, CH2), 2.18 (2H, t, J ¼ 6.4 Hz,
CH2), 2.85 (2H, t, J ¼ 6.4 Hz, CH2), 6.60 (2H, s, NH2), 7.40 (1H, d,
J ¼ 8.4 Hz, ArH), 7.59?7.61 (1H, dd, J ¼ 2.0 Hz, J ¼ 1.6 Hz, ArH), 7.86
(1H, d, J ¼ 2.0 Hz, ArH). Anal. calcd for C18H13Cl2N3: C, 63.17; H,
3.83; N, 12.28. Found: C, 63.23; H, 3.76; N, 12.17.
2-Amino-4-(3,4-dimethylphenyl)-5,6,7,8-tetrahydronaphthalene-1,3-
dicarbonitrile (4f)
Mp: 210–212 ꢀC. IR (KBr) v: 3464, 3359, 3238, 2941, 2865, 2213, 1636,
.
1565, 1505, 1454, 1282, 1262, 1172, 1125, 1031, 816, 734 cmꢁ1 1H
NMR (400 MHz, DMSO-d6) (d, ppm): 1.55 (2H, t, J ¼ 2.4 Hz, CH2),
1.681.74 (2H, m, CH2), 2.09–2.18 (2H, m, CH2), 2.26 (3H, s, CH3),
2.28 (3H, s, CH3), 2.83 (2H, t, J ¼ 6.4 Hz, CH2), 6.40 (2H, s, NH2),
6.96 (1H, d, J ¼ 7.6 Hz, ArH), 7.03 (1H, s, ArH), 7.25 (1H, d, J ¼ 7.6 Hz,
ArH). Anal. calcd. for C20H19N3: C, 79.70; H, 6.35; N, 13.94. Found: C,
79.77; H, 6.29; N, 13.85.
2-Amino-4-(3,4-dimethoxyphenyl)-5,6,7,8-tetrahydronaphthalene-1,3-
dicarbonitrile (4g)
Mp: 223–225 ꢀC. IR (KBr) v: 3428, 3349, 3247, 2965, 2924, 2863, 2838,
2213, 1644, 1566, 1516, 1456, 1436, 1319, 1255, 1172, 1143, 1027, 819,
.
735 cmꢁ1 1H NMR (400 MHz, DMSO-d6) (d, ppm): 1.56 (2H, t,
J ¼ 6.0 Hz, CH2), 1.72 (2H, t, J ¼ 6.0 Hz, CH2), 2.25 (2H, t, J ¼ 6.0 Hz,
CH2), 2.85 (2H, t, J ¼ 6.4 Hz, CH2), 3.75 (3H, s, OCH3), 3.81 (3H, s,
OCH3), 6.40 (2H, s, NH2), 6.80 (1H, d, J ¼ 8.0 Hz, ArH), 6.86 (1H, d,
J ¼ 1.2 Hz, ArH), 7.06 (1H, d, J ¼ 8.4 Hz, ArH). Anal. calcd. for
C20H19N3: C, 72.05; H, 5.74; N, 12.60. Found: C, 72.13; H, 5.65; N,
12.71.
2-Amino-4-(4-fluorophenyl)-5,6,7,8-tetrahydronaphthalene-1,3-
dicarbonitrile (4h)
Mp: 255–256 ꢀC. IR (KBr) v: 3420, 3342, 3255, 3232, 2951, 2873, 2212,
1
1649, 1605, 1511, 1456, 1392, 1272, 1231, 1165, 845, 808, 755 cmꢁ1. H
NMR (400 MHz, DMSO-d6) (d, ppm): 1.56 (2H, t, J ¼ 6.0 Hz, CH2),
1.72 (2H, t, J ¼ 6.0 Hz, CH2), 2.15 (2H, t, J ¼ 6.4 Hz, CH2), 2.84 (2H, t,
J ¼ 6.4 Hz, CH2), 6.47 (2H, s, NH2), 7.35 (4H, d, J ¼ 7.2 Hz, ArH). Anal.

3538
L. Rong et al.
calcd. for C18H14FN3: C, 74.21; H, 4.84; N, 14.42. Found: C, 74.13; H,
4.91; N, 14.31.
5-Amino-2,3-dihydro-7-p-tolyl-1H-indene-4,6-dicarbonitrile (4i)
Mp: 181–182 ꢀC. R (KBr) v: 3409, 3350, 3252, 2957, 2217, 1655, 1571,
1516, 1459, 1403, 1366, 1319, 1305, 1265, 1180, 1119, 1021, 815,
.
745 cmꢁ1 1H NMR (400 MHz, DMSO-d6) (d, ppm): 1.99 (2H, q,
J ¼ 7.2 Hz, 7.6 Hz, CH2), 2.38 (3H, s, CH3), 2.62 (2H, t, J ¼ 7.6 Hz,
CH2), 2.99 (2H, t, J ¼ 7.2 Hz, CH2), 6.53 (2H, s, NH2), 7.31 (4H, s,
ArH). Anal. calcd. for C18H15N3: C, 79.10; H, 5.53; N, 15.37. Found:
C, 79.21; H, 5.41; N, 15.31.
5-Amino-7-(2-chlorophenyl)-2,3-dihydro-1H-indene-4,6-dicarbonitrile (4j)
Mp: 162–164 ꢀC. IR (KBr) v: 3417, 3352, 3251, 2955, 2221, 1654, 1637,
1573, 1507, 1460, 1420, 1369, 1319, 1304, 1268, 1211, 1054, 1031, 771,
.
746 cmꢁ1 1H NMR (400 MHz, DMSO-d6) (d, ppm): 2.02 (2H, q,
J ¼ 7.2 Hz, 7.6 Hz, CH2), 2.45 (2H, t, J ¼ 7.6 Hz, CH2), 3.04 (2H, t,
J ¼ 7.2 Hz, CH2), 6.67 (2H, s, NH2), 7.38–7.40 (1H, m, ArH), 7.47–7.54
(2H, m, ArH), 7.63–7.66 (1H, m, ArH). Anal. calcd. for C17H12ClN3:
C, 69.51; H, 4.12; N, 14.30. Found: C, 69.45; H, 4.19; N, 14.22.
5-Amino-7-(4-chlorophenyl)-2,3-dihydro-1H-indene-4,6-dicarbonitrile (4k)
Mp: 152–154 ꢀC. IR (KBr) v: 3417, 3350, 3251, 2954, 2220, 1653,
1573, 1460, 1434, 1419, 1319, 1305, 1268, 1055, 1031, 770,
.
745 cmꢁ1 1H NMR (400 MHz, DMSO-d6) (d, ppm): 2.01 (2H, q,
J ¼ 7.2 Hz, 7.6 Hz, CH2), 2.45 (2H, t, J ¼ 7.6 Hz, CH2), 3.04 (2H, t,
J ¼ 7.2 Hz, CH2), 6.67 (2H, s, NH2), 7.40 (1H, d, J ¼ 8.0 Hz, ArH),
7.45–7.63 (2H, m, ArH), 7.64 (1H, d, J ¼ 8.0 Hz, ArH). Anal. calcd.
for C17H12ClN3: C, 69.51; H, 4.12; N, 14.30. Found: C, 69.56; H,
4.07; N, 14.39.
5-Amino-7-(3-chlorophenyl)-2,3-dihydro-1H-indene-4,6-dicarbonitrile (4l)
Mp: 161–165 ꢀC. IR (KBr) v: 3409, 3347, 3249, 2958, 2213, 1653, 1567,
1481, 1457, 1406, 1319, 1305, 1274, 1260, 1694, 1080, 882, 793, 745,
.
693 cmꢁ1 1H NMR (400 MHz, DMSO-d6) (d, ppm): 2.00 (2H, q,
J ¼ 7.2 Hz, 7.6 Hz, CH2), 2.61 (2H, t, J ¼ 7.6 Hz, CH2), 3.02 (2H, t,

Synthesis of 2,6-dicyanoanilines
3539
J ¼ 7.2 Hz, CH2), 6.64 (2H, s, NH2), 7.38–7.43 (1H, m, ArH), 7.47–7.58
(3H, m, ArH). Anal. calcd. for C17H12ClN3: C, 69.51; H, 4.12; N,
14.30. Found: C, 69.58; H, 4.19; N, 14.26.
5-Amino-7-(2,4-dichlorophenyl)-2,3-dihydro-1H-indene-4,6-
dicarbonitrile (4m)
Mp: 201–203 ꢀC. IR (KBr) v: 3421, 3347, 3251, 2965, 2216, 1652, 1590,
1751, 1485, 1460, 1419, 1385, 1271, 1255, 1104, 1055, 893, 819,
.
780 cmꢁ1 1H NMR (400 MHz, DMSO-d6) (d, ppm): 2.01 (2H, q,
J ¼ 7.2 Hz, 7.6 Hz, CH2), 2.46 (2H, t, J ¼ 7.2 Hz, CH2), 3.04 (2H, t,
J ¼ 7.6 Hz, CH2), 6.72 (2H, s, NH2), 7.45 (1H, d, J ¼ 8.0 Hz, ArH),
7.58–7.60 (1H, dd, J1 ¼ 2.0 Hz, J2 ¼ 2.0 Hz, ArH), 7.85 (1H, d, J ¼ 2.0 Hz,
Hz, ArH). Anal. calcd. for C17H11Cl2N3: C, 62.21; H, 3.38; N, 12.80.
Found: C, 62.30; H, 3.30; N, 12.88.
5-Amino-7-(3,4-dichlorophenyl)-2,3-dihydro-1H-indene-4,6-
dicarbonitrile (4n)
Mp: 257–259 ꢀC; IR (KBr) v: 3461, 3359, 3233, 2919, 2215, 1626, 1564,
1543, 1473, 1455, 1436, 1373, 1315, 1282, 1249, 1132, 1030, 894,
1
756 cmꢁ1. H NMR (400 MHz, DMSO-d6) (d, ppm): 1.95–2.09 (2H, m,
CH2), 2.62–2.2.69 (2H, m, CH2), 2.93–3.10 (2H, m, CH2), 6.78 (2H, s,
NH2), 7.48–7.52 (1H, m, ArH), 7.67–7.75 (1H, m, ArH), 7.81–7.85
(1H, m, ArH). Anal. calcd for C17H11Cl2N3: C, 62.21; H, 3.38; N,
12.80. Found: C, 62.38; H, 3.45; N, 12.73.
5-Amino-7-(3,4-dimethylphenyl)-2,3-dihydro-1H-indene-4,6-
dicarbonitrile (4o)
ꢀ
Mp: 140–142 C. IR (KBr) v: 3416, 3350, 3251, 2945, 2918, 2216, 1655,
1571, 1505, 1458, 1383, 1379, 1318, 1305, 1267, 1125, 1018, 823,
749 cmꢁ1 1H NMR (400 MHz, DMSO-d6) (d, ppm): 1.98 (2H, q,
.
J ¼ 7.2 Hz, 7.6 Hz, CH2), 2.27 (3H, s, CH3), 2.28 (3H, s, CH3), 2.61
(2H, t, J ¼ 7.2 Hz, CH2), 3.00 (2H, t, J ¼ 7.6 Hz, CH2), 6.54 (2H, s,
NH2), 7.12 (1H, d, J ¼ 7.8 Hz, ArH), 7.18 (1H, s, ArH), 7.25 (1H, d,
J ¼ 8.0 Hz, ArH). Anal. calcd. for C19H17N3: C, 79.41; H, 5.96; N,
14.62. Found: C, 79.48; H, 5.89; N, 14.73.

3540
L. Rong et al.
5-Amino-2,3-dihydro-7-(4-methoxyphenyl)-1H-indene-4,6-
dicarbonitrile (4p)
ꢀ
Mp: 189–191 C. IR (KBr) v: 3403, 3345, 3249, 2967, 2936, 2217, 1655,
1609, 1565, 1517, 1458, 1408, 1365, 1318, 1294, 1254, 1176, 1032, 838,
761 cmꢁ1 1H NMR (400 MHz, DMSO-d6) (d, ppm): 1.99 (2H, q,
.
J ¼ 7.2 Hz, 7.6 Hz, CH2), 2.64 (2H, t, J ¼ 7.6 Hz, CH2), 3.00 (2H, t,
J ¼ 7.2 Hz, CH2), 3.82 (3H, s, OCH3), 6.52 (2H, s, NH2), 7.06 (2H, d,
J ¼ 8.4 Hz, ArH), 7.37 (2H, d, J ¼ 8.4 Hz, ArH). Anal. calcd. for
C18H15N3O: C, 74.72; H, 5.23; N, 14.52. Found: C, 74.58; H, 5.32; N
14.63.
X-ray Crystallography for 4a
Empirical formula C19H17N3, Fw ¼ 287.36, T ¼ 294(2) K, monclinic,
space group C2=c, a ¼ 22.837 (6); b ¼ 7.906(2), c ¼ 17.920(4), a ¼ 90ꢀ,
b ¼ 105.995(5)ꢀ, c ¼ 90ꢀ, V ¼ 3110.8(14)3, Z ¼ 8, Dc ¼ 1.227 Mg=m3, k
(MoKa) ¼ 0.71073, l ¼ 0.074 mmꢁ1, F(000) ¼ 1216. 2.36ꢀ < h < 25.00ꢀ,
R ¼ 0.0492, wR ¼ 0.1184, S ¼ 0.999. Largest diff. peak and hole: 0.184
and ꢁ 0.159 eꢁ3
.
X-Ray Crystallography for 5
Empirical formula C19H15ClN4, Fw ¼ 334.8, T ¼ 294(2) K, monoclinic,
space group p 2(1)=c, a ¼ 13.0487 (18), b ¼ 9.1339 (12), c ¼ 13.9867
(19), a ¼ 90ꢀ, b ¼ 90.124(2)ꢀ, c ¼ 90ꢀ, V ¼ 1667.0 (4)3, Z ¼ 4,
Dc ¼ 1.334 Mg=m3, k (MoKa) ¼ 0.71073; l ¼ 0.236 mmꢁ1, F(000) ¼ 696,
1.56ꢀ < h < 26.43ꢀ, R ¼ 0.0394, wR ¼ 0.0913, S ¼ 1.034. Largest diff. peak
and hole: 0.227 and ꢁ0.268 eꢁ3
.
ACKNOWLEDGMENTS
We thank the PeiYu Foundation (07PYL06) of Xuzhou Normal Univer-
sity for financial support.
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