Y. V. D. Nageswar et al.
FULL PAPER
chromatography using silica gel (ethyl acetate/hexane, 1:9) to ob-
tain the pure product 3a (181 mg, 94%) as a pale-yellow oil. All
the products were characterized by 1H and 13C NMR, and MS
analyses and compared with literature values. The same procedure
was extended for further cycles.
δ = 7.48–7.45 (d, J = 7.88 Hz, 1 H), 7.23–7.20 (m, 2 H), 7.03–6.95
(m, 5 H), 6.28 (s, 1 H), 3.86 (s, 3 H), 2.26 (s, 3 H) ppm. 13C NMR
(75 MHz, CDCl3): δ = 158.9, 138.5, 137.0, 130.7, 129.1, 128.0,
120.9, 119.8, 119.5, 114.5, 109.9, 100.9, 55.4, 13.3 ppm. IR: ν
=
˜
max
2924, 1585, 1518, 1456, 1134, 1014, 876, 756 cm–1. ESI-MS: m/z =
238 [M + H].
1-Phenyl-1H-indole (3a):[13] Table 2, Entry 1. Yield: 189 mg (98%);
yellowish oil. H NMR (300 MHz, CDCl3): δ = 7.62–7.60 (d, J = 1-Phenyl-1H-indole-5-carbonitrile (3i):[27g] Table 2, Entry 9. Yield:
1
7.96 Hz, 1 H), 7.51–7.44 (m, 5 H), 7.33–7.27 (m, 2 H), 7.20–7.04
(m, 2 H), 6.62–6.61 (d, J = 2.3 Hz, 1 H) ppm. 13C NMR (75 MHz,
CDCl3): δ = 139.8, 135.8, 129.5, 129.2, 127.9, 126.4, 124.3, 122.3,
198 mg (91%); yellowish oil. 1H NMR (400 MHz, CDCl3): δ =
7.59–7.35 (m, 7 H), 7.32–7.30 (m, 1 H), 7.15–7.11 (m, 1 H), 6.65–
6.64 (d, J = 3.39 Hz, 1 H) ppm. 13C NMR (100 MHz, CDCl3): δ
= 139.2, 134.6, 130.9, 129.6, 129.0, 128.0, 126.8, 125.1, 124.2, 123.5,
121.0, 120.3, 110.4, 103.5 ppm. IR: ν
= 2923, 1596, 1503, 1137,
˜
max
745, 689 cm–1. ESI-MS: m/z = 194.5 [M + H].
113.6, 111.9, 102.9 ppm. IR: ν
= 2924, 2250, 1567, 1538, 1074,
˜
max
956, 845, 723 cm–1. ESI-MS: m/z = 219.5 [M + H].
1-(4-Methoxyphenyl)-1H-indole (3b):[18g] Table 2, Entry 2. Yield:
205 mg (92%); yellowish oil. 1H NMR (400 MHz, CDCl3): δ =
7.61–7.59 (d, J = 7.32 Hz, 1 H), 7.39–7.36 (m, 3 H), 7.23–7.20 (m,
1 H), 7.15–7.06 (m, 2 H), 6.99–6.96 (m, 2 H), 6.58–6.57 (d, J =
5-Nitro-1-phenyl-1H-indole (3j):[27g] Table 2, Entry 10 Yield: 216 mg
(91%); yellow solid; m.p. 83 °C. H NMR (400 MHz, CDCl3): δ =
1
8.65–8.60 (d, J = 1.7 Hz, 1 H), 8.12–8.06 (d, J = 9.0 Hz, 1 H),
2.93 Hz, 1 H), 3.85 (s, 3 H) ppm. 13C NMR (100 MHz, CDCl3): δ 7.58–7.40 (m, 7 H), 6.83–6.82 (d, J = 3.02 Hz, 1 H) ppm. 13C NMR
= 158.1, 136.2, 132.7, 128.8, 128.2, 125.8, 122.0, 120.9, 120.0, 114.6,
(100 MHz, CDCl3): δ = 142.1, 138.5, 131.2, 129.9, 128.4, 127.7,
110.2, 102.8, 55.4 ppm. IR: ν
= 2924, 1586, 1248, 1118, 1014,
124.7, 118.2, 117.8, 110.3, 105.6, 96.1 ppm. IR: ν
= 2924, 1587,
˜
˜
max
max
821, 787 cm–1. ESI-MS: m/z = 224 [M + H].
1518, 1014, 821, 787 cm–1. ESI-MS: m/z = 239 [M + H].
1-p-Tolyl-1H-indole (3c):[25] Table 2, Entry 3. Yield: 190 mg (92%);
1-(4-Nitrophenyl)-1H-indole (3k):[27a] (Table 2, Entry 17. Yield:
1
1
yellowish oil. H NMR (400 MHz, CDCl3): δ = 7.61–7.58 (d, J = 162 mg (68%); yellow solid; m.p.[35] 132 °C. H NMR (300 MHz,
7.55 Hz, 1 H), 7.46–7.44 (d, J = 7.55 Hz, 1 H), 7.36–7.33 (d, J = CDCl3): δ = 8.42–8.37 (m, 2 H), 7.71–7.64 (m, 4 H), 7.39–7.37 (m,
8.30 Hz, 2 H), 7.25–7.22 (m, 3 H), 7.19–7.05 (m, 2 H), 6.59–6.58
(d, J = 3.77 Hz, 1 H), 2.41 (s, 3 H) ppm. 13C NMR (100 MHz,
CDCl3): δ = 137.2, 136.2, 135.9, 130.1, 129.1, 128.0, 124.2, 122.1,
1 H), 7.32–7.21 (m, 2 H), 6.78–6.77 (d, J = 3.77 Hz, 1 H) ppm. 13
NMR (75 MHz, CDCl3): δ = 148.1, 145.4, 144.2, 131, 125.5, 122.7,
C
120.1, 118, 111.4, 104.2 ppm. IR: ν
= 1599, 1553, 1459, 1388,
˜
max
121.0, 120.1, 110.4, 103.1, 21.0 ppm. IR: ν
= 2924, 1587, 1518,
1324, 1277, 1224, 774, 746, 708 cm–1. ESI-MS: m/z = 239 [M + H].
˜
max
1014, 821, 787 cm–1. ESI-MS: m/z = 208 [M + H].
1-[4-(1H-Indol-1-yl)phenyl]ethanone (3l):[23e] Table 2, Entry 18.
1-(2-Methoxyphenyl)-1H-indole (3d):[23e] Table 2, Entry 4. Yield: Yield: 164 mg (70%); yellowish oil. H NMR (300 MHz, CDCl3):
1
173 mg (78%); yellowish oil. 1H NMR (400 MHz, CDCl3): δ =
7.64–7.61 (m, 1 H), 7.45–7.33 (m, 2 H), 7.25–7.05 (m, 6 H), 6.62–
6.61 (d, J = 3.39 Hz, 1 H), 3.79 (s, 3 H) ppm. 13C NMR (100 MHz,
CDCl3): δ = 138.0, 133.9, 133.7, 129.2, 128.9, 128.1, 127.5, 126.8,
δ = 7.78–7.64 (d, J = 1.9 Hz, 1 H), 7.39–7.51 (m, 4 H), 7.09–7.33
(m, 4 H), 6.52–6.53 (d, J = 3.12 Hz, 1 H), 2.52 (s, 3 H) ppm. 13C
NMR (75 MHz, CDCl3): δ = 191.2, 144.1, 133.3, 130.1, 129.2,
125.6, 121, 120, 118.3, 110.2, 104.1, 29.2 ppm. IR: ν
= 3200,
˜
max
125.0, 123.5, 122.0, 121.6, 55.6 ppm. IR: ν
= 2926, 1577, 1248,
1657, 1519, 1568, 1456, 1314, 1213, 845, 745 cm–1. ESI-MS: m/z =
˜
max
1112, 1011, 821, 788 cm–1. ESI-MS: m/z = 224 [M + H].
236 [M + H].
1-[4-(Trifluoromethyl)phenyl]-1H-indole (3e):[12b] Table 2, Entry 5. Methyl 4-(1H-Indol-1-yl)benzoate (3m):[17a] Table 2, Entry 19.
1
1
Yield: 232 mg (89%); yellowish oil. H NMR (400 MHz, CDCl3): Yield: 163 mg (65%); yellowish oil. H NMR (400 MHz, CDCl3):
δ = 7.66–7.58 (m, 3 H), 7.49–7.43 (m, 1 H), 7.41–7.36 (m, 2 H), δ = 8.25–8.18 (d, J = 8.03 Hz, 1 H), 7.70–7.52 (m, 3 H), 7.39–7.34
7.26–7.23 (m, 2 H), 7.20–7.08 (m, 1 H), 6.64–6.61 (d, J = 3.02 Hz,
1 H) ppm. 13C NMR (100 MHz, CDCl3): δ = 142.7, 135.4, 129.6,
127.3, 126.8, 125.7, 123.8, 122.9, 121.4, 120.9, 110.3, 104.8 ppm.
(m, 2 H), 7.29–7.10 (m, 3 H), 6.73–6.72 (d, J = 3.77 Hz, 1 H) ppm.
13C NMR (100 MHz, CDCl3): δ = 165.5, 143.8, 135, 131.3, 129.8,
127.6, 127.5, 123.3, 122.0, 121.6, 121.0, 110.7, 104, 52.0 ppm. IR:
IR: νmax = 1585, 1346, 1416, 1350, 1020, 1013, 810, 776 cm–1. ESI-
ν
= 3045, 2945, 1705, 1538, 1456, 1213, 1052, 777, 745,
˜
˜
max
MS: m/z = 262 [M + H].
686 cm–1. ESI-MS: m/z = 252 [M + H].
1-(Pyridin-3-yl)-1H-indole (3f):[27g] Table 2, Entry 6. Yield: 174 mg Ethyl 4-(1H-Indol-1-yl)benzoate (3n):[27g] Table 2, Entry 20. Yield:
1
(90%); yellowish oil. H NMR (400 MHz, CDCl3): δ = 7.61–7.58 177 mg (67%); yellowish oil. 1H NMR (300 MHz, CDCl3): δ =
(d, J = 8.12 Hz, 1 H), 7.51–7.48 (d, J = 8.49 Hz, 1 H), 7.41–7.37
(m, 1 H), 7.27–7.05 (m, 6 H), 6.58–6.57 (d, J = 3.21 Hz, 1 H) ppm.
8.21–8.23 (m, 2 H), 7.51–7.78 (m, 4 H), 7.10–7.28 (m, 3 H), 6.71–
6.72 (t, J = 3.75 Hz, 1 H), 3.99–4.04 (br. s, 2 H), 1.33 (t, J =
13C NMR (100 MHz, CDCl3): δ = 138.5, 136.0, 128.9, 127.8, 126.0, 8.02 Hz, 3 H) ppm. 13C NMR (75 MHz, CDCl3): δ = 165.1, 146.3,
123.6, 122.4, 121.0, 120.5, 114.7, 110.5, 103.3, 96.1 ppm. IR: ν
130.5, 126.1, 125.4, 122.3, 121.1, 120.5, 118.5, 111.4, 104.1, 61.2,
˜
max
= 2898, 2100, 1585, 1521, 1456, 1134, 1014, 876, 756 cm–1. ESI- 14.9 ppm. IR: ν
= 3046, 3100, 2948, 1978, 1705, 1538, 1503,
˜
max
MS: m/z = 195.2 [M + H].
1213, 1345, 1052, 777, 748, 694 cm–1. ESI-MS: m/z = 266 [M + H].
2-Methyl-1-phenyl-1H-indole (3g):[32] Table 2, Entry 7. Yield: 1-Phenyl-1H-pyrazole (4a):[13] Table 3, Entry 1. Yield: 118 mg
184 mg (89%); yellowish oil. 1H NMR (300 MHz, CDCl3): δ =
(82%); yellowish oil. H NMR (300 MHz, CDCl3): δ = 7.89–7.88
1
7.53–7.23 (m, 6 H), 7.06–6.98 (m, 3 H), 6.32 (s, 1 H), 2.30 (s, 3 H) (m, 1 H), 7.69–7.65 (m, 3 H), 7.45–7.39 (m, 2 H), 7.27–7.20 (m, 1
ppm. 13C NMR (75 MHz, CDCl3): δ = 138.1, 137.9, 136.9, 129.3,
H), 6.42 (t, J = 2.26 Hz, 1 H) ppm. 13C NMR (75 MHz, CDCl3):
δ = 140.9, 140.1, 129.4, 126.8, 126.5, 119.2, 107.5 ppm. IR: ν
128.1, 127.9, 127.6, 120.9, 119.9, 119.4, 109.9, 101.2, 13.3 ppm. IR:
=
˜
max
ν
˜
max = 2924, 2167, 1739, 1587, 1558, 1064, 857, 767 cm–1. ESI-MS: 1601, 1592, 1464, 1157, 837, 750, 749 cm–1. ESI-MS: m/z = 145 [M
m/z = 208 [M + H].
+ H].
1-(4-Methoxylphenyl)-2-methyl-1H-indole (3h):[23e] Table 2, Entry 8. 1-(4-Fluorophenyl)-1H-pyrazole (4b):[13] Table 3, Entry 2. Yield:
1
Yield: 213 mg (90%); yellowish oil. H NMR (300 MHz, CDCl3): 131 mg (81%); white solid; m.p. 62 °C. 1H NMR (300 MHz,
6682
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Eur. J. Org. Chem. 2010, 6678–6684