8721
11. 2,3-Diphenyl-1-(phenylsulfonyl)indole (3a) (83%): Mp 174–176°C; IR (KBr) max 1446, 1356, 1176, 1086 cm−1; 1H
NMR (CDCl3) l 8.43 (m, 1H), 7.51–7.41 (m, 5H), 7.36–7.21 (m, 11H), 7.11–7.07 (m, 2H); 13C NMR (CDCl3)
l 138.4, 137.5, 137.0, 133.7, 132.8, 132.3, 131.0, 130.7, 130.0, 128.9, 128.7, 128.4, 127.5, 127.2, 127.1, 125.5, 125.1,
124.5, 120.2, 116.5. HRMS m/z calcd for C26H19NO2S (M+) 409.1137, found 409.1138. Anal. calcd for
C26H19NO2S: C, 76.26; H, 4.68; N, 3.42; S, 7.83. Found: C, 76.34; H, 4.73; N, 3.50; S, 7.82. 2,3-Bis(4-
methylphenyl)-1-(phenylsulfonyl)indole (3b) (98%): Mp 153–155°C; IR (KBr)
1444, 1383, 1180, 1079, 1000,
max
826 cm−1; H NMR (d6-acetone) l 8.35 (m, 1H), 7.62 (m, 1H), 7.54 (m, 2H), 7.48–7.40 (m, 4H), 7.32 (m, 1H),
7.19 (m, 2H), 7.13 (m, 2H), 7.09 (m, 2H), 7.02 (m, 2H), 2.36 (s, 3H), 2.28 (s, 3H); 13C NMR (CDCl3) l 138.5,
138.3, 137.5, 137.0, 136.8, 133.7, 132.1, 131.0, 129.8, 129.2, 128.8, 128.3, 128.1, 127.1, 125.3, 124.9, 124.4, 120.2,
116.5, 21.7, 21.4. HRMS m/z calcd for C28H23NO2S (M+) 437.1450, found 437.1446. Anal. calcd for
C28H23NO2S: C, 76.86; H, 5.30; N, 3.20; S, 7.33. Found: C, 76.98; H, 5.37; N, 3.26; S, 7.30. 2,3-Bis(4-
methoxyphenyl)-1-(phenylsulfonyl)indole (3c) (85%): Mp 197–199°C; IR (KBr) max 1607, 1500, 1444, 1287, 1242,
1175, 1076, 1030, 832 cm−1; 1H NMR (d6-acetone) l 8.35 (m, 1H), 7.61–7.42 (m, 7H), 7.32 (m, 1H), 7.20 (m, 2H),
7.06 (m, 2H), 6.85 (m, 4H), 3.84 (s, 3H), 3.76 (s, 3H); 13C NMR (CDCl3) l 159.8. 158.6, 138.4, 137.5, 136.6,
133.7, 133.6, 131.1, 130.9, 128.8, 127.1, 125.2, 125.1, 124.41, 124.39, 123.2, 120.1, 116.5, 113.9, 113.0, 55.4, 55.3.
HRMS m/z calcd for C28H23NO4S (M+) 469.1348, found 469.1353. Anal. calcd for C28H23NO4S: C, 71.62; H,
1
4.94; N, 2.98; S, 6.82. Found: C, 71.44; H, 5.03; N, 3.03; S, 6.71. 2,3-Bis(3-methoxyphenyl)-1-(phenylsul-
1
fonyl)indole (3d) (87%): Mp 112.5–114.5°C; IR (KBr)
1597, 1446, 1374, 1262, 1178, 1090 cm−1; H NMR
max
(d6-acetone) l 8.37 (m, 1H), 7.63–7.58 (m, 3H), 7.50–7.45 (m, 4H), 7.35 (m, 1H), 7.25–7.19 (m, 2H), 6.96 (m, 1H),
6.89 (m, 2H), 6.81–6.76 (m, 2H), 6.66 (m, 1H), 3.74 (s, 3H), 3.62 (s, 3H); 13C NMR (CDCl3) l 159.5, 158.7, 138.4,
137.5, 136.8, 134.1, 133.8, 132.2, 130.5, 129.4, 128.9, 128.5, 127.2, 125.5, 124.9, 124.8, 124.5, 122.4, 120.3, 117.6,
116.4, 115.2, 114.8, 113.3, 55.5, 55.3. HRMS m/z calcd for C28H23NO4S (M+) 469.1348, found 469.1344. Anal.
calcd for C28H23NO4S: C, 71.62; H, 4.94; N, 2.98; S, 6.82. Found: C, 71.42; H, 5.03; N, 3.04; S, 6.71.
2,3-Bis(4-chlorophenyl)-1-(phenylsulfonyl)indole (3e) (55%): Mp 150.5–152°C; IR (KBr)
1495, 1444, 1371,
max
1186, 1090, 995, 832 cm−1; 1H NMR (d6-acetone) l 8.36 (m, 1H), 7.65 (m, 1H), 7.58 (m, 2H), 7.51–7.33 (m, 11H),
7.16 (m, 2H); 13C NMR (CDCl3) l 138.2, 137.5, 135.8, 135.1, 134.0, 133.43, 133.40, 131.2, 130.9, 130.2, 129.2,
129.0, 128.9, 128.1, 127.0, 125.9, 124.8, 124.4, 120.1, 116.5. HRMS m/z calcd for C26H17NCl2O2S (M+) 477.0357,
found 477.0350. Anal. calcd for C26H17NCl2O2S: C, 65.28; H, 3.58; N, 2.93; Cl, 14.82. Found: C, 65.29; H, 3.68;
N, 2.92; Cl, 14.74. 2,3-Bis(4-formylphenyl)-1-(phenylsulfonyl)indole (3f) (50%): Mp 208–210°C; IR (KBr)
max
1702, 1607, 1444, 1376, 1186, 1085, 843 cm−1, H NMR (CDCl3) l 10.07 (s, 1H), 9.97 (s, 1H), 8.44 (m, 1H), 7.84
1
(m, 2H), 7.77 (m, 2H), 7.53–7.43 (m, 7H), 7.38–7.32 (m, 3H), 7.24 (m, 2H); 13C NMR (CDCl3) l 192.0, 191.9,
138.9, 137.8, 137.7, 136.8, 136.3, 136.2, 135.3, 134.3, 132.8, 130.6, 130.0, 129.8, 129.2, 129.0, 127.0, 126.5, 125.2,
125.1, 120.2, 116.7. HRMS m/z calcd for C28H19NO4S (M+) 465.1035, found 465.1041. Anal. calcd for
C28H19NO4S: C, 72.24; H, 4.12; N, 3.01. Found: C, 71.87; H, 4.31; N, 2.99. 2,3-Bis(3-formylphenyl)-1-(phenylsul-
1
fonyl)indole (3g) (44%): Mp 152–154°C; IR (KBr)
1700, 1450, 1376, 1189, 805 cm−1; H NMR (CDCl3) l
max
10.01 (s, 1H), 9.95 (s, 1H), 8.40 (m, 1H), 7.97–7.37 (m, 16H); 13C NMR (CDCl3) l 192.1, 191.8, 138.1, 137.5,
136.8, 136.4, 136.0, 135.9, 135.7, 134.3, 133.5, 133.2, 131.8, 130.9, 130.1, 129.9, 129.5, 129.2, 129.1, 128.6, 126.9,
126.3, 125.0, 124.6, 120.1, 116.4. HRMS m/z calcd for C28H19NO4S (M+) 465.1035, found 465.1032. Anal. calcd
for C28H19NO4S: C, 72.24; H, 4.12; N, 3.01. Found: C, 71.72; H, 4.14; N, 2.95.
12. General procedure: A mixture of 1a (0.100 g, 0.196 mmol), arylboronic acid (0.432 mmol), palladium acetate (4.4
mg, 0.0196 mmol), tri(o-tolyl)phosphine (12 mg, 0.039 mmol), and potassium carbonate (0.33 g, 2.4 mmol) in a
3-neck round bottom flask was flushed with nitrogen for 10 min. A solution of acetone (10 mL) and water (5 mL)
was added by syringe and the mixture was heated at 70°C (reflux) for 5 h under nitrogen (monitored by TLC).
The cooled reaction mixture was extracted with ether. The ether layer was dried (MgSO4) and evaporated to
afford crude product. Flash chromatography over silica gel (EtOAc/hexane, 30/70) gave pure products.11
Recrystallization from mixtures of ether and hexane afforded analytical samples.11
13. For a recent review of these and other indole ring syntheses, see Gribble, G. W. J. Chem. Soc., Perkin Trans. 1
2000, 1045–1075.
.