Helvetica Chimica Acta – Vol. 92 (2009)
1005
After completion of the reaction (as indicated by TLC), the solvent was removed under reduced
pressure, then the mixture was diluted with H2O and extracted with AcOEt. The org. layer was dried
(Na2SO4) and concentrated under reduced pressure. The crude mixture was purified by column
chromatography (CC) to obtain the pure product. The characteristic data of some representative
compounds are given below.
3-[1-(2-Chlorophenyl)-2-nitroethyl]-1H-indole (3b). Brick colour solid. M.p. 1428. IR (KBr): 3438,
3060, 2919, 1546, 1379. 1H-NMR (200 MHz, CDCl3): 4.95 (d, J ¼ 7.5, 2 H); 5.65 – 5.75 (m, 1 H); 7.00 – 7.50
(m, 9 H); 8.10 (br. s, 1 H). FAB-MS: 324 ([M þ Na]þ), 302 ([M þ 1]þ), 100.
3-[2-Nitro-1-(2-nitrophenyl)ethyl]-1H-indole (3c). Semisolid. IR (KBr): 3423, 3045, 2933, 2865,
1602, 1547, 1450. 1H-NMR (200 MHz, CDCl3): 4.91 – 5.15 (m, 2 H); 5.82 (t, J ¼ 7.5, 1 H); 6.90 (t, J ¼ 7.5,
1 H); 7.02 – 7.10 (m, 1 H); 7.14 (t, J ¼ 7.7, 1 H); 7.20 – 7.30 (m, 2 H); 7.30 – 7.70 (m, 2 H); 7.87 (d, J ¼ 7.7,
1 H); 8.10 (br. s, 1 H). FAB-MS: 312 ([M þ 1]þ), 311 (Mþ).
3-[1-(Naphthalen-1-yl)-2-nitroethyl]-1H-indole (3e). Black solid. M.p. 1658. IR (KBr): 3423, 3054,
2922, 2855, 1602, 1548, 1450. 1H-NMR (200 MHz, CDCl3): 5.00 – 5.10 (m, 2 H); 5.98 – 6.10 (m, 1 H); 7.00
(t, J ¼ 7.3, 2 H); 7.18 (t, J ¼ 7.3, 1 H); 7.29 (d, J ¼ 8.0, 1 H); 7.30 – 7.40 (m, 4 H); 7.55 (quint, J ¼ 7.3, 1 H);
8.00 (br. s, 1 H); 8.25 (d, J ¼ 8.0, 1 H). FAB-MS: 339 ([M þ Na]þ), 154.
3-[1-(2-Chlorophenyl)-2-nitroethyl]-2-methyl-1H-indole (3h). Brick colour solid. M.p. 1218. IR
1
(KBr): 3414, 3058, 2918, 1547, 1461, 1376. H-NMR (200 MHz, CDCl3): 2.40 (s, 3 H); 5.10 (d, J ¼ 8.3,
2 H); 5.40 – 5.50 (m, 1 H); 7.00 – 7.50 (m, 8 H); 7.82 (br. s, 1 H). FAB-MS: 338 ([M þ Na]þ), 315, 254, 102.
3-[1-(4-Methoxyphenyl)-2-nitroethyl]-2-methyl-1H-indole (3j). White solid. M.p. 1208. IR (KBr):
3431, 3011, 2936, 1602, 1550, 1367. 1H-NMR (200 MHz, CDCl3): 2.45 (s, 3 H); 3.7 (s, 3 H); 5.00 – 5.20 (m,
3 H); 6.80 (d, J ¼ 8.8, 2 H); 7.00 – 7.40 (m, 8 H); 7.81 (br. s, 1 H). FAB-MS: 310 (Mþ).
5-Bromo-3-[1-(2-chlorophenyl)-2-nitroethyl]-1H-indole (3n). Brick colour solid. M.p. 1408. IR
1
(KBr): 3444, 3130, 2920, 1548, 1458. H-NMR (200 MHz, CDCl3): 4.90 (d, J ¼ 7.5, 2 H); 5.59 – 5.66 (m,
1 H); 7.10 – 7.50 (m, 8 H); 8.10 (br. s, 1 H). FAB-MS: 403 ([M þ Na]þ), 380, 303, 210.
5-Bromo-3-[1-(4-methoxyphenyl)-2-nitroethyl]-1H-indole (3p). Orange colour solid. M.p. 1458. IR
1
(KBr): 3385, 2921, 1609, 1546, 1510, 1248. H-NMR (200 MHz, CDCl3): 3.77 (s, 3 H); 4.80 – 5.10 (m,
3 H); 6.80 (d, J ¼ 9.0, 2 H); 7.00 (d, J ¼ 1.5, 1 H); 7.18 (d, J ¼ 8.3, 2 H); 7.25 (d, J ¼ 6.7, 2 H); 7.48 (s, 1 H);
8.05 (br. s, 1 H). FAB-MS: 377 ([M þ 2]þ), 352, 303, 134, 100.
3-[1-(2-Chlorophenyl)-2-nitroethyl]-1H-indole-5-carbonitrile (3t). Red colour solid. M.p. 1368. IR
(KBr): 3382, 2922, 2853, 2220, 1616, 1543, 1429. 1H-NMR (200 MHz, CDCl3): 4.92 (d, J ¼ 7.5, 2 H); 5.64 –
5.72 (m, 1 H); 7.05 (d, J ¼ 7.5, 1 H); 7.18 (t, J ¼ 7.5, 1 H); 7.22 – 7.40 (m, 4 H); 7.48 (d, J ¼ 7.5, 1 H); 7.67 (s,
1 H); 8.70 (br. s, 1 H). FAB-MS: 349 ([M þ Na]þ), 326 ([M þ 1]þ).
3-[1-(2-Chlorophenyl)-2-nitroethyl]-5-methoxy-1H-indole (3z). Brick colour solid. M.p. 1228. IR
(KBr): 3452, 2926, 1550, 1477, 1207, 1034. 1H-NMR (200 MHz, CDCl3): 4.90 – 4.95 (m, 2 H); 5.65 (t, J ¼
7.5, 1 H); 6.72 – 6.82 (m, 2 H); 7.05 (s, 1 H); 7.15 – 7.20 (m, 4 H); 7.40 (d, J ¼ 8.3, 1 H); 7.90 (br. s, 1 H).
FAB-MS: 331 (Mþ), 284, 270, 100.
5-Methoxy-3-[2-nitro-1-(2-nitrophenyl)ethyl]-1H-indole (3a1). Semisolid. IR (KBr): 3432, 3054,
2922, 1598, 1549, 1445, 1250. 1H-NMR (200 MHz, CDCl3): 3.71 (s, 3 H); 5.00 – 5.10 (m, 2 H); 5.75 (t, J ¼
7.5, 1 H); 6.60 – 6.65 (m, 1 H); 6.79 (dd, J ¼ 2.2, 9.0, 1 H); 7.08 – 7.10 (m, 1 H); 7.18 (d, J ¼ 9.0, 1 H); 7.39 –
7.52 (m, 3 H); 7.90 (d, J ¼ 7.5, 1 H); 8.00 (br. s, 1 H). FAB-MS: 341 (Mþ).
3-[1-(Furan-2-yl)-2-nitroethyl]-1H-pyrrole (3v1). Viscous liquid. IR (KBr): 3420, 2923, 2853, 1549.
1H-NMR (200 MHz, CDCl3): 4.70 – 4.91 (m, 2 H); 4.98 (t, J ¼ 7.5, 1 H); 5.98 – 6.20 (m, 3 H); 6.27 – 6.36
(m, 1 H); 6.56 – 6.73 (m, 1 H); 7.35 – 7.41 (m, 1 H); 8.14 (br. s, 1 H). FAB-MS: 206 (Mþ).
REFERENCES
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