Month 2017
A Green Synthesis of 2-Amino-4-(9H-carbazole-3-yl)thiophene-3-carbonitriles by
a Step-wise and One-pot Three-component Gewald Reaction
120.3, 120.7, 120.9, 122.7, 123.4, 124.7, 125.8, 127.0,
140.7, 142.2, 181.7. (Aromatic C): MS (positive mode):
m/z = 300 [M + H]+. Anal. Calcd (%) for C20H17N3; C,
80.24. H, 5.72. N, 14.04. Found: C, 80.28. H, 5.70. N,
1H, Ar-H), 8.17–8.15 (d, 1H, Ar-H), 8.35–8.32 (d, 1H,
Ar-H); 13C-NMR (100 MHz, CDCl3): 13.9, 37.7
(aliphatic C) 89.3, 104.7, 108.7, 116.2, 119.1, 119.3,
120.7, 122.9, 123.2, 125.1, 125.3, 126.0, 139.8, 140.4,
141.1, 163.3. (Aromatic C): MS (positive mode): m/
z = 318 [M + H]+. Anal. Calcd (%) for C19H15N3S; C,
14.02.
2-(1-(6-Bromo-9-ethyl-9H-carbazole-yl)propylidene)
malononitrile (4h).
Yellow solid; yield (68%); m.p.
71.90. H, 4.76. N, 13.24. Found: C, 71.82. H, 4.81. N, 13.15.
198–200°C; IR (KBr): 3048, 2950, 2851, 2230, 1715,
1588, 1447, 1366, 1215, 805; 1H-NMR (400 MHz,
CDCl3/TMS): δ 1.32–1.20 (t, 3H, CH3), 1.59–1.46 (t,
3H, CH3), 3.17–3.11 (m, 2H, CH2), 4.41–4.36 (m, 2H,
CH2), 7.36–728 (t, 1H, Ar-H), 7.51–7.49 (d, 1H, Ar-H),
7.65–7.62 (m, 1H, Ar-H), 7.75–7.73 (m, 1H, Ar-H),
8.29–8.27 (m, 2H, Ar-H); 13C-NMR (100 MHz, CDCl3):
13.6, 13.8, 30.1, 37.9 (aliphatic) 80.7, 108.1, 108.9,
109.2, 113.6, 114.3, 120.3, 120.8, 120.9, 122.6, 123.3,
124.7, 125.8, 127.0, 140.6, 142.1, 181.7. (Aromatic C):
MS (positive mode): m/z = 379 [M + H]+. Anal. Calcd
(%) for C20H16BrN3; C, 63.50. H, 4.26. N, 11.11.
2-Amino-4-(9-butyl-9H-carbazole-3-yl)thiophene-3-
carbonitrile (5c).
Dark blue solid; yield (85%); m.p.
98–100°C; IR (KBr): 3430, 3320, 3194, 2958, 2871,
2197, 1715, 1594, 1457, 1386, 1205, 805; 1H-NMR
(400 MHz, CDCl3/TMS): δ 1.00–0.96 (t, 3H, CH3),
1.46–1.43 (t, 2H, CH2), 1.19–1.89 (d, 2H, CH2), 4.35–
4.33 (d, 2H, CH2), 4.94 (s, 2H, NH2), 6.38 (s, 1H, Ar-H),
7.29–7.28 (s, 1H, Ar-H), 7.51–7.47 (m, 3H, Ar-H), 7.72–
7.70 (s, 1H, Ar-H), 8.17–8.15 (d, 1H, Ar-H), 8.32 (s, 1H,
Ar-H); 13C-NMR (100 MHz, CDCl3): 13.9, 20.6, 31.2,
42.9 (aliphatic C) 89.2, 104.7, 108.9, 116.2, 119.1, 119.2,
120.6, 122.8, 123.1, 125.1, 125.22, 125.98, 140.29,
140.91, 141.08, 163.4. (Aromatic C): MS (positive
mode): m/z = 346 [M + H]+. Anal. Calcd (%) for
C21H19N3S; C, 73.01. H, 5.54. N, 12.16. Found: C,
Found: C, 63.54. H, 4.28. N, 11.13.
2,20-(1,1-(9-Ethyl-9H-carbazole-3,6-diyl)bis(ethan-1-yl-1-
ylidene))dimalononitrile (16). Yellow solid; yield (65%);
m.p. 170–172°C; IR (KBr): 3084, 2948, 2851,2230, 2158,
73.12. H, 5.48. N, 12.26.
2-Amino-4-(6-bromo-9-methyl-9H-carbazole-3-yl)thiophene-
3-carbonitrile (8). Brown solid; yield (80%); m.p. 258–
1
1715, 1688, 1447, 1366, 1215, 805; H-NMR (400 MHz,
CDCl3/TMS): δ 1.02–1.00 (t, 3H, CH3), 2.86 (s, 6H, CH3,
CH3), 4.06–4.01 (m, 2H, CH2), 7.28–726 (d, 2H, Ar-H),
7.45–7.43 (d, 2H, Ar-H), 7.53 (s, 1H, Ar-H), 8.15 (s,
1H, Ar-H); 13C-NMR (100 MHz, CDCl3): 13.2, 23.4,
39.3 (aliphatic C) 80.2, 110.4, 115.4, 118.5, 127.5,
119.2, 138.5, 148.7, 180.0. (Aromatic C): MS (positive
mode): m/z = 376 [M + H]+. Anal. Calcd (%) for
C24H17N5; C, 76.78. H, 4.56. N, 18.65. Found: C, 76.74.
H, 4.58. N, 18.67.
260°C; IR (KBr): 3320, 3205, 2197, 1621, 1506, 1452,
1380, 1287, 1238, 1145, 854, 783, 706; 1H-NMR
(400 MHz, DMSO-d6/TMS): δ 3.88 (s, 3H, CH3), 6.51
(s, 1H, Ar-H), 7.26 (s, 2H, NH2), 7.68–7.59 (m, 4H, Ar-
H), 8.39–8.38 (t, 2H, Ar-H); 13C-NMR (100 MHz,
DMSO-d6): 29.7 (aliphatic C) 84.4, 109.9, 111.5, 111.9,
117.4, 119.8, 121.6, 123.4, 124.3, 126.3, 162.5, 128.8,
139.9, 140.2, 140.9, 166.7. (Aromatic C): MS (positive
mode): m/z = 381 [M + H]+. Anal. Calcd (%) for
C18H12BrN3S; C, 56.55. H, 3.16. N, 10.99. Found: C,
Spectral data for title compounds. 2-Amino-4-(9-methyl-
9H-carbazole-3-yl)thiophene-3-carbonitrile (5a). Dark blue
solid; yield (90%); m.p. 110–112°C; IR (KBr): 3420,
56.48. H, 3.23. N, 10.85.
2-Amino-5-methyl-4-(9-methyl-9H-carbazole-3-yl)thiophene-
3-carbonitrile (14a). Brown solid; yield (75%); m.p. 190–
3330, 3284, 2948, 2851, 2158, 1715, 1588, 1447, 1366,
1
1215, 805; H-NMR (400 MHz, CDCl3/TMS): δ 3.86 (s,
192°C; IR (KBr): 3320, 3240, 3124, 2958, 2841, 2167,
1715, 1584, 1437, 1356, 1226, 809; H-NMR (400 MHz,
3H, CH3), 4.91 (s, 2H, NH2), 6.38 (s, 1H, Ar-H), 7.30–
721 (t, 1H, Ar-H), 7.45–7.41 (m, 2H, Ar-H), 7.54–7.50
(t, 1H, Ar-H), 7.73–7.71 (m, 1H, Ar-H), 8.16–8.14 (d,
1H, Ar-H), 8.31 (s, 1H, Ar-H); 13C-NMR (100 MHz,
CDCl3): 29.20 (aliphatic C) 89.2, 104.7, 108.7, 116.2,
119.1, 119.2, 120.5, 122.7, 123.0, 125.1, 125.3, 126.1,
140.8, 141.1, 141.4, 163.4. (Aromatic C): MS (positive
mode): m/z = 304 [M + H]+. Anal. Calcd (%) for
C18H13N3S; C, 71.26. H, 4.32. N, 13.85. Found: C,
1
CDCl3/TMS): δ 2.30 (s, 3H, CH3), 3.87 (s, 3H, CH3),
7.28–7.26 (m, 1H, Ar-H), 7.53–742 (m, 4H, Ar-H), 8.08–
8.07 (d, 1H, Ar-H), 8.13–8.12 (d, 1H, Ar-H); 13C-NMR
(100 MHz, CDCl3): 13.5, 29.2 (aliphatic C) 90.6, 108.5,
108.6, 116.2, 118.5, 119.1, 120.5, 121.0, 122.7, 122.8,
124.5, 125.9, 126.8, 136.1, 140.5, 141.4, 159.57.
(Aromatic C): MS (positive mode): m/z = 318 [M + H]+.
Anal. Calcd (%) for C19H15N3S; C, 71.90. H, 4.76. N,
13.24. Found: C, 71.95. H, 4.82. N, 13.15.
71.15. H, 4.41. N, 13.72.
2-Amino-4-(9-ethyl-9H-carbazole-3-yl)thiophene-3-carbonitrile
(5b). Dark blue solid; yield (89%); m.p. 112–114°C; IR
2-Amino-4-(6-bromo-9-methyl-9H-carbazole-3-yl)-5-methylthio
(KBr): 3410, 3340, 3184, 2958, 2851, 2177, 1715, 1564,
1437, 1376, 1205, 805; 1H-NMR (400 MHz, CDCl3/
TMS): δ 1.49–1.45 (t, 3H, CH3), 4.43–4.32 (m, 2H,
CH2), 4.92 (s, 2H, NH2), 6.39 (s, 1H, Ar-H), 7.29–7.26
(m, 1H, Ar-H), 7.52–7.44 (m, 3H, Ar-H), 7.73–7.71 (m,
phene-3-carbonitrile (12a).
(70%); m.p. 242–244°C; IR (KBr): 3430, 3298,
Light yellow solid; yield
3205, 2197, 1621, 1512, 1446, 1282, 1137, 1019,
1
783; H-NMR (400 MHz, DMSO-d6/TMS): δ 2.17 (s,
3H, CH3), 3.88 (s, 3H, CH3), 7.06 (s, 1H, Ar-H), 7.46–
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet