M. De Rosa, A. Soriente / Tetrahedron 66 (2010) 2981–2986
2985
(hexane/AcOEt 8/2) 0.51; nmax(liquid film)¼3430, 3125, 2920,
2360, 1554, 1503, 1433, 1375, 1337, 1184, 1147, 1095, 1012, 918, 797,
730; dH (400 MHz; CDCl3) 3.54 (s, 3H), 4.85 (dd, J¼12.8, 8.0 Hz,
1H), 4.92–5.04 (m, 2H), 6.04–6.05 (m, 1H), 6.09–6.12 (m, 2H),
6.29–6.31 (m, 1H), 6.60–6.61 (m, 1H), 7.36–7.37 (m, 1H). dC
(100 MHz; CDCl3) 33.6, 35.2, 79.0, 106.5, 107.1, 107.6, 110.4, 122.9,
127.0, 142.5, 151.1; m/z 221 (Mþ).
7.35–7.23 (m, 6H), 7.86 (br s, 1H). dC (100 MHz; CDCl3) 11.9, 40.2,
55.8, 78.3, 101.4, 108.4, 110.3, 111.2, 127.0, 127.2, 128.7, 130.0, 133.7,
139.3, 153.8; m/z 310 (Mþ).
4.2.15. 5-Chloro-2-methyl-3-(2-nitro-1-phenyl-ethyl)-1H-indole
(15a). Yield (125.6 mg, 80%) as colorless oil; (found: C, 64.83; H,
4.77; N, 8.88. C17H15ClN2O2 requires C, 64.87; H, 4.80; N, 8.90%); Rf
(hexane/AcOEt 8/2) 0.31; nmax(liquid film)¼3410, 2920, 1548, 1510,
1432; dH (300 MHz; CDCl3) 2.29 (s, 3H), 5.06–5.21 (m, 3H), 7.02–7.11
(m, 2H), 7.22–7.34 (m, 6H), 7.93 (br s, 1H). dC (75.5 MHz; CDCl3) 11.9,
40.2, 78.4, 108.4, 111.7, 117.8, 121.5, 125.2, 127.1, 127.3, 127.8, 128.9,
133.7, 134.7, 138.9; m/z 314 (Mþ).
4.2.9. 2-Methyl-3-[2-nitro-1-(4-nitro-phenyl)-ethyl]-1H-indole
(5b). Yield (161 mg, 99%) as brown solid, mp 165–166 ꢀC; (found: C,
62.73; H, 4.67; N, 12.95. C17H15N3O4 requires C, 62.76; H, 4.65; N,
12.92%); Rf (hexane/AcOEt 8/2) 0.49; nmax(neat)¼3750, 2920, 2850,
1549, 1515, 1347; dH (400 MHz; CDCl3) 2.41 (s, 3H), 5.07–5.13 (m,
1H), 5.25–5.31 (m, 2H), 7.03–7.07 (m, 1H), 7.02–7.16 (m, 1H),
7.27–7.30 (m, 2H), 7.47 (d, J¼8.8, 2H), 8.11 (br s, 1H), 8.13 (d,
J¼8.8 Hz, 2H). dC (100 MHz; CDCl3) 11.9, 40.2, 80.9, 102.5, 110.9,
117.9, 120.0, 121.6, 123.9, 126.2, 128.2, 133.1, 135.4, 146.8, 147.0; m/z
325 (Mþ).
Acknowledgements
This work was supported by the Italian Ministry of Education
(MIUR).
References and notes
4.2.10. 3-[1-(4-Bromo-phenyl)-2-nitro-ethyl]-2-methyl-1H-indole
(5c). Yield (177.2 mg, 99%) as pale yellow oil; (found: C, 56.81; H,
4.18; N, 7.82. C17H15BrN2O2 requires C, 56.84; H, 4.21; N, 7.80%); Rf
(hexane/AcOEt 8/2) 0.47; nmax(liquid film)¼3420, 2920, 1549,
1487, 1375; dH (300 MHz; CDCl3) 2.33 (s, 3H), 5.04–5.20 (m, 3H),
7.06–7.25 (m, 5H), 7.35 (d, J¼7.8 Hz, 1H), 7.41 (d, J¼8.4 Hz, 2H),
8.03 (br s, 1H). dC (75 MHz; CDCl3) 11.9, 39.9, 78.2, 108.2, 110.8,
118.3, 119.8, 121.0, 121.4, 126.5, 129.0, 131.8, 132.9, 135.3, 138.5; m/z
358 (Mþ).
`
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4.2.11. 3-[1-(4-Chloro-phenyl)-2-nitro-ethyl]-2-methyl-1H-indole
(5d). Yield (155.4 mg, 99%) as pale yellow solid, mp 155–156 ꢀC;
(found: C, 64.90; H, 4.78; N, 8.91. C17H15ClN2O2 requires C, 64.87; H,
4.80; N, 8.90%); Rf (hexane/AcOEt 8/2) 0.48; nmax(KBr)¼3413, 3056,
2918, 1546, 1463, 1375; dH (400 MHz; CDCl3) 2.36 (s, 3H), 5.06 (dd,
J¼10.8, 7.4 Hz, 1H), 5.13–5.23 (m, 2H), 7.02–7.06 (m, 1H), 7.10–7.14
(m, 1H), 7.24–7.27 (m, 5H), 7.32 (d, J¼8 Hz, 1H), 8.02 (br s, 1H). dC
(100 MHz; CDCl3) 12.0, 39.8, 78.3, 108.3, 110.8, 118.3, 119.8, 121.4,
126.5, 128.6, 128.8, 132.9, 135.4, 137.4, 138.0; m/z 314 (Mþ).
4.2.12. 3-[1-(2-Methoxy-phenyl)-2-nitro-ethyl]-2-methyl-1H-indole
(5f). Yield (150.3 mg, 97%) as brown solid, mp 128–129 ꢀC; (found:
C, 69.68; H, 5.90; N, 9.07. C18H18N2O3 requires C, 69.66; H, 5.85; N,
9.03%); Rf (hexane/AcOEt 8/2) 0.30; nmax (KBr)¼3407, 2925, 1612,
1549, 1509, 1463, 1375, 1249, 1114, 1025, 743; dH (250 MHz; CDCl3)
2.36 (s, 3H), 3.88 (s, 3H), 5.15 (dd, J¼12.4, 9.9 Hz, 1H), 5.26 (dd,
J¼12.4, 5.8 Hz, 1H), 5.48 (dd, J¼9.9, 5.8 Hz, 1H), 6.86–7.37 (m, 8H),
7.81 (br s, 1H). dC (62.9 MHz; CDCl3) 11.8, 35.6, 55.2, 77.5, 107.7,
110.4, 110.6, 118.7, 119.4,119.5, 120.4, 120.8, 127.2, 128.2, 128.3, 133.2,
135.2, 156.7; m/z 310 (Mþ).
4.2.13. Dimethyl-{4-[1-(2-methyl-1H-indol-3-yl)-2-nitro-ethyl]-phe-
nyl}-amine (5g). Yield (155.0 mg, 96%) as orange solid, mp 161–
162 ꢀC; (found: C, 70.59; H, 6.58; N, 13.01. C19H21N3O2 requires C,
70.57; H, 6.55; N, 12.99%); Rf (hexane/AcOEt 8/2) 0.31;
nmax(KBr)¼3425, 2980, 1547, 1380, 1290; dH (400 MHz; CDCl3) 2.38
(s, 3H), 2.90 (s, 3H), 5.07–5.19 (m, 3H), 6.67 (d, J¼8.8 Hz, 2H), 7.0–
7.48 (m, 7H), 7.90 (br s, 1H). dC (62.9 MHz; CDCl3) 12.0, 39.7, 40.8,
79.0, 109.2, 110.6, 111.8, 113.1, 118.8, 119.6, 121.1, 126.9, 128.1, 131.5,
132.6, 135.4, 149.4; m/z 323 (Mþ).
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4.2.14. 5-Methoxy-2-methyl-3-(2-nitro-1-phenyl-ethyl)-1H-indole
(13a). Yield (139.5 mg, 96%) as pale yellow oil; (found: C, 69.72; H,
5.88; N, 9.01. C18H18N2O3 requires C, 69.66; H, 5.85; N, 9.03%); Rf
(hexane/AcOEt 8/2) 0.47; nmax(liquid film)¼3398, 3065, 1560, 1480,
1372; dH (400 MHz; CDCl3) 2.31 (s, 3H), 3.78 (s, 3H), 5.05–5.13 (m,
1H), 5.17–5.24 (m, 2H), 6.77–6.83(m, 1H), 7.11 (d, J¼8.0 Hz, 1H),