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5.3.27. 5-Amino-1-(3,5-dimethylbenzyl)-1H-indole (34). A
mixture of 5-nitro-1H-indole (320 mg) and 1.2 equiv of
potassium carbonate, 1.0 equiv of 3,5-dimethylbenzyl
bromide and N,N-dimethylformamide (20 mL) was stir-
red at 50 °C overnight. The whole was poured into
water, and the product was extracted with ethyl acetate.
The organic layer was washed with water and brine,
dried over anhydrous MgSO4, and filtered. The filtrate
was concentrated and the residue was purified by silica
gel column chromatography (n-hexane–ethyl ace-
tate = 3:1 as the eluant) to give 490 mg (87.5%) of the
precursor nitro derivative 31: 1H NMR (500 MHz,
CDCl3): d 8.61 (d, J = 2.1 Hz, 1H), 8.08 (dd, J = 9.0,
2.1 Hz, 1H), 7.32 (d, J = 9.0 Hz, 1H), 7.27 (s, 1H),
7.26 (s, 4H), 5.28 (s, 2H), 2.26 (s, 6H);MS(FAB) m/z
281 (M+H)+. Anal. Calcd for C17H16N2O2: C, 72.84;
H, 5.75;N, 9.99. Found: C, 72.57;H, 5.75;N, 9.97.
NMR (500 MHz, CDCl3): d 8.54 (d, J = 3.0 Hz, 1H),
8.47 (d, J = 3.0 Hz, 1H), 8.22 (dd, J = 9.0, 3.0 Hz, 1H),
8.08 (d, J = 9.0 Hz, 1H), 7.74 (d, J = 9.0 Hz, 1H), 7.50
(s, 1H), 7.20 (s, 1H), 6.82 (d, J = 3.0 Hz, 1H), 2.33 (s,
6H);MS(FAB) m/z 331 (M+H)+. Anal. Calcd for
C16H14N2O4S: C, 58.17;H, 4.27;N, 8.48. Found: C,
58.06;H, 4.47;N, 8.33.
5.3.30. 5-Amino-1-(3,5-dimethylbenzenesulfonyl)-1H-
indole (36). The nitro derivative 33 was hydrogenated
using 10% palladium on charcoal, to afford the desired
1
compound (36): H NMR (500 MHz, CDCl3): d 7.77
(d, J = 9.0 Hz, 1H), 7.45 (d, J = 3.9 Hz, 1H), 7.43 (s,
2H), 7.11 (s, 1H), 6.78 (d, J = 2.1 Hz, 1H), 6.71 (dd,
J = 9.0, 2.1 Hz, 1H), 6.48 (d, J = 3.9 Hz, 1H), 3.87 (br,
2H), 2.29 (s, 6H);MS(FAB) m/z 300 (M+H)+. Anal.
Calcd for C16H16N2O2S: C, 63.98;H, 5.37;N, 9.33.
Found: C, 63.68;H, 5.09;N, 9.21.
The nitro derivative (31) (280 mg) was hydrogenated
using 10% palladium on charcoal, to afford 240 mg
(96.0%) of the desired compound (34): 1H NMR
(500 MHz, CDCl3): d 7.08 (d, J = 9.0 Hz, 1H), 7.03 (d,
J = 3.0 Hz, 1H), 6.95 (d, J = 3.0 Hz, 1H), 6.88 (s, 1H),
6.74 (s, 2H), 6.64 (dd, J = 9.0, 3.0 Hz, 1H), 6.34 (d,
J = 3.0 Hz, 1H), 5.16 (s, 2H), 2.24 (s, 6H), 1.56 (br,
2H);MS(FAB) m/z 250 (M+H)+. Anal. Calcd for
C17H16N2O2Æ1/6H2O: C, 80.59;H, 7.29;N, 11.06.
Found: C, 80.71;H, 7.30;N, 10.83.
5.3.31. 2,3-Dihydro-1-(3,5-dimethylbenzyl)-5-nitro-1H-
indole (43). This compound was prepared from 2,3-dihy-
dro-5-nitro-1H-indole, using the same procedures as de-
1
scribed for the preparation of 32: H NMR (500 MHz,
DMSO-d6): d 8.05 (d, J = 9.0 Hz, 1H), 7.91 (s, 1H),
6.94 (s, 1H), 6.86 (s, 2H), 6.35 (d, J = 9.0 Hz, 1H),
4.35 (s, 2H), 3.63 (t, J = 8.6 Hz, 2H), 3.09 (t,
J = 8.6 Hz, 2H), 2.30 (s, 6H);MS(FAB)
m/z 283
(M+H)+. Anal. Calcd for C17H184N2O2: C, 72.32;H,
6.43;N, 9.92. Found: C, 72.30;H, 6.49;N, 9.87.
5.3.28. 1-(3,5-Dimethylbenzoyl)-5-nitro-1H-indole (35). A
mixture of 5-nitro-1H-indole (320 mg) and 1.2 equiv of
60% NaH, and N,N-dimethylformamide (10 mL) was
stirred for 30 min at 0 °C under an argon atmosphere.
Then, a solution of 1.0 equiv of 3,5-dimethylbenzoyl
chloride in N,N-dimethylformamide (5 mL) was added
dropwise at 0 °C. After the addition was complete, the
reaction mixture was stirred overnight at 60 °C. The
whole was poured into water, and the product was ex-
tracted with ethyl acetate. The organic layer was washed
with water and brine, dried over anhydrous MgSO4, and
filtered. The filtrate was concentrated and the residue
was purified by silica gel column chromatography (n-
hexane–ethyl acetate = 3:1 as the eluant) to give
500 mg (85.0%) of the precursor nitro compound 32:
1H NMR (500 MHz, CDCl3): d 8.54 (d, J = 2.1 Hz,
1H), 8.47 (d, J = 9.0 Hz, 1H), 8.27 (dd, J = 9.0, 2.1 Hz,
1H), 7.51 (d, J = 3.9 Hz, 1H), 7.35 (s, 2H), 7.28
(s, 1H), 6.75 (d, J = 3.9 Hz, 1H), 2.42 (s, 6H);MS(FAB)
m/z, 295. Anal. Calcd for C17H14N2O3: C, 69.38;H,
4.79;N, 9.52. Found: C, 69.17;H, 5.06;N, 9.42. The
nitro derivative 32 (294 mg) was hydrogenated using 10%
palladium on charcoal, to afford 233 mg (88.3%) of the
5.3.32. 2,3-Dihydro-1-(3,5-dimethylbenzoyl)-5-nitro-1H-
indole (44). This compound was prepared from 2,3-dihy-
dro-5-nitro-1H-indole, using the same procedures as de-
1
scribed for the preparation of 33: H NMR (500 MHz,
CDCl3):
d 8.07 (s, 2H), 7.15 (s, 4H), 4.18 (t,
J = 8.6 Hz, 2H), 3.20 (t, J = 8.6 Hz, 2H), 2.36 (s, 6H);
MS(FAB) m/z 297 (M+H)+. Anal. Calcd for
C17H16N2O3: C, 68.85;H, 5.44;N, 9.45. Found: C,
68.85;H, 5.51;N, 9.42.
5.3.33.
2,3-Dihydro-1-(3,5-dimethylbenzesulfonyl)-5-
nitro-1H-indole (45). This compound was prepared from
2,3-dihydro-5-nitro-1H-indole, using the same proce-
dures as described for the preparation of 32: H NMR
1
(500 MHz, CDCl3): d 8.13 (d, J = 9.0 Hz, 2H), 7.68 (d,
J = 9.0 Hz, 1H), 7.45 (s, 2H), 7.23 (s, 1H), 4.05 (t,
J = 8.6 Hz, 2H), 3.10 (t, J = 8.6 Hz, 2H), 2.35 (s, 6H);
MS(FAB) m/z 333 (M+H)+. Anal. Calcd for
C17H16N2O3S: C, 57.82;H, 4.85;N, 8.43. Found: C,
57.96;H, 4.89;N, 8.47.
5.3.34. 5-Amino-2,3-dihydro-1-(3,5-dimethylbenzyl)-1H-
indole (46). This compound was prepared by the hydro-
genation of 43 with 10% palladium on charcoal: 1H
NMR (500 MHz, DMSO-d6): d 7.01 (s, 1H), 6.97 (d,
J = 8.6 Hz, 1H), 6.92 (s, 2H), 6.89 (s, 1H), 6.58 (d,
J = 8.6 Hz, 1H), 4.18 (s, 2H), 4.05 (t, J = 8.6 Hz, 2H),
3.10 (t, J = 8.6 Hz, 2H), 2.23 (s, 6H);MS(FAB) m/z 252
(M+H)+. Anal. Calcd for C17H20N2Æ2HCl: C, 62.77;H,
6.82;N, 8.61. Found: C, 62.61;H, 6.65;N, 8.56.
1
desired compound (35): H NMR (500 MHz, CDCl3):
d 8.20 (d, J = 9.0 Hz, 1H), 7.30 (s, 2H), 7.21 (d,
J = 3.9 Hz, 1H), 7.20 (s, 1H), 6.86 (d, J = 2.1 Hz, 1H),
6.76 (dd, J = 9.0, 2.1 Hz, 1H), 6.43 (d, J = 3.9 Hz, 1H),
2.38 (s, 6H), 1.56 (br, 2H);MS(FAB)
m/z 265
(M+H)+. Anal. Calcd for C17H16N2OÆ1HCl: C, 66.88;
H, 5.78;N, 9.18. Found: C, 67.04;H, 6.06;N, 8.73.
5.3.29. 1-(3,5-Dimethylbenzenesulfonyl)-5-nitro-1H-
indole (33). This compound was prepared using the same
5.3.35. 5-Amino-2,3-dihydro-1-(3,5-dimethylbenzoyl)-1H-
indole (47). This compound was prepared by the
1
procedures as described for the preparation of 32: H