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silica gel flash column chromatography (8:1 hexanes/ether,
RfZ0.34), to afford an orange solid upon cooling in the
freezer overnight (20 mg, 40%); mp 41–43 8C; H NMR
7.4 Hz), 2.37 (s, 3H), 1.62 (p, 2H, JZ7.4 Hz), 1.30 (m, 8H),
0.90 (t, 3H, JZ6.9 Hz); 13C NMR (75 MHz, CDCl3) d
135.40, 130.73, 129.00, 120.90, 119.09, 118.35, 112.69,
110.27, 32.15, 31.01, 29.82, 29.50, 24.33, 22.92, 14.35,
11.86; IR (neat) 3407 (s), 2930 (s), 2860 (s), 1466 (s), 1306
(m), 739 (s); CIMS (methane) m/z: 230 (MCH), 144.
1
(400 MHz, CDCl3) d 7.69 (br s, 1H), 7.5 (d, 1H, JZ7.5 Hz),
7.27 (d, 1H, JZ7.0 Hz), 7.11 (m, 2H), 2.73 (t, 2H, JZ
7.5 Hz), 2.25 (s, 3H), 1.64 (p, 2H, JZ7.5 Hz), 1.39 (sextet,
2H, JZ7.6 Hz), 0.95 (t, 3H, JZ7.5 Hz); 13C NMR
(100 MHz, CDCl3) d 135.49, 135.29, 129.56, 121.04,
119.11, 118.21, 110.28, 106.98, 32.05, 26.04, 22.60,
14.11, 8.69; IR (neat) 3403 (s), 2969 (s), 2924 (s), 1470
(s), 1336 (m), 1306 (m), 744 (s); CIMS (methane) m/z: 188
(MCH), 144.
4.4.2. 3-Allyl-2-phenylindole (4m).27 Synthesized follow-
ing procedure E, except the reaction was heated at 90 8C for
19 h. The product was purified by silica gel flash column
chromatography (8:1 hexanes/ether, RfZ0.3), to afford a
yellow/white powder (26 mg, 52%): mp 98–99 8C, lit. mp28
1
72–73 8C; H NMR (300 MHz, CDCl3) d 8.02 (br s, 1H),
4.3.3. 2-Ethyl-3-propylindole (4i). Synthesized following
either procedure C or D. The product was purified by silica
gel flash column chromatography (8:1 hexanes/ether, RfZ
0.26), to afford a waxy orange solid after standing (10 mg,
7.56 (m, 3H), 7.44 (t, 2H, JZ7.3 Hz), 7.34 (m, 2H), 7.19 (t,
1H, JZ8.1 Hz), 7.11 (t, 1H, JZ7.9 Hz), 6.12 (m, 1H), 5.08
(m, 2H), 3.61 (dt, 2H, JZ1.8, 5.6 Hz); 13C NMR (75 MHz,
CDCl3) d 137.57, 136.10, 135.01, 133.16, 129.55, 129.04,
128.02, 127.86, 122.53, 119.84, 119.59, 115.38, 110.96,
110.66, 29.15; IR (neat) 3402 (s), 3078 (w), 3014 (w), 1610
(w), 1455 (s), 1306 (m), 992 (m), 928 (m), 759 (s), 700 (m);
CIMS (methane) m/z: 234 (MCH), 206.
1
20%); H NMR (400 MHz, CDCl3) d 7.73 (br s, 1H), 7.52
(d, 1H, JZ6.8 Hz), 7.28 (d, 1H, JZ7.3 Hz), 7.09 (m, 2H),
2.76 (q, 2H, JZ7.6 Hz), 2.67 (t, 2H, JZ7.6 Hz), 1.65
(sextet, 2H, JZ7.5 Hz), 1.28 (t, 3H, JZ7.6 Hz), 0.95 (t, 3H,
JZ7.4 Hz); 13C NMR (100 MHz, CDCl3) d 136.75, 135.40,
129.02, 120.98, 119.10, 118.57, 111.60, 110.39, 26.35,
24.31, 19.54, 14.56, 14.42; IR (neat) 3402 (s), 2959 (s),
2929 (s), 1461 (s), 1321 (m), 744 (s); CIMS (methane) m/z:
188 (MCH), 158.
4.4.3. 3-Allyl-5-methoxy-2-phenylindole (4n). Syn-
thesized following procedure E, except the reaction was
heated at 90 8C for 15 h. The product was purified by silica
gel flash column chromatography (45 mL of 8:1 hexanes/
ether, then 4:1 hexanes/ether), to afford a white powder
(27 mg, 54%): mp 102–104 8C; 1H NMR (500 MHz,
CDCl3) d 7.95 (br s, 1H), 7.55 (d, 2H, JZ8.1 Hz), 7.46
(t, 2H, JZ7.9 Hz), 7.36 (t, 1H, JZ7.4 Hz), 7.28 (d, 1H, JZ
8.7 Hz), 7.04 (sd, 1H, JZ2.4 Hz), 6.87 (dd, 1H, JZ2.4,
8.8 Hz), 6.13 (m, 1H), 5.11 (m, 2H), 3.87 (s, 3H), 3.60 (dt,
2H, JZ1.8, 5.7 Hz); 13C NMR (125 MHz, CDCl3) d 154.32,
137.44, 135.97, 133.26, 131.33, 130.06, 129.02, 127.95,
127.80, 115.37, 112.53, 111.71, 110.44, 101.52, 56.14,
29.20; IR (neat) 3402 (m), 2939 (w), 1625 (m), 1486 (s),
1456 (s), 1222 (s), 1037 (w), 763 (m), 699 (m); CIMS
(methane) m/z: 264 (MCH), 249.
4.3.4. 5-Methoxy-3-methyl-2-phenylindole (4j).24 Syn-
thesized following procedure D. The product was purified
by silica gel flash column chromatography (4:1 hexanes/
ether, RfZ0.3), to afford a white powder (16 mg, 32%): mp
116–117 8C, lit. mp25 114–116 8C; 1H NMR (400 MHz,
CDCl3) d 7.89 (br s, 1H), 7.57 (d, 2H, JZ8.3 Hz), 7.47
(t, 2H, JZ8.9 Hz), 7.35 (t, 1H, JZ7.4 Hz), 7.27 (d, 1H, JZ
8.3 Hz), 7.04 (d, 1H, JZ2.4 Hz), 6.87 (dd, 1H, JZ2.4,
8.7 Hz), 3.90 (s, 3H), 2.44 (s, 3H); 13C NMR (125 MHz,
CDCl3) d 154.32, 135.16, 133.58, 131.18, 130.60, 129.00,
127.85, 127.47, 112.62, 111.65, 108.69, 101.00, 56.16, 9.97;
IR (neat) 3412 (m), 2929 (w), 1620 (m), 1585 (m), 1486 (s),
1461 (s), 1291 (m), 1217 (s), 774 (m), 699 (m); CIMS
(methane) m/z: 238 (MCH), 223.
4.4.4. 3-Allyl-2-(30,50-dibromophenyl)-5-methoxyindole
(4o). Synthesized following procedure E, except the reac-
tion was heated at 90 8C for 15 h. The product was purified
by silica gel flash column chromatography (4:1 hexanes/
ether, RfZ0.3), to afford a pale yellow powder (15 mg,
29%): mp 111–114 8C; 1H NMR (500 MHz, CDCl3) d 7.89
(br s, 1H), 7.60 (s, 3H), 7.25 (d, 1H, JZ8.8 Hz), 6.99 (sd,
1H, JZ2.4 Hz), 6.88 (dd, 1H, JZ2.4, 8.8 Hz), 6.07 (m, 1H),
5.08 (m, 2H), 3.84 (s, 3H), 3.55 (dt, 2H, JZ1.8, 5.7 Hz); 13C
NMR (125 MHz, CDCl3) d 154.56, 136.77, 136.60, 132.93,
132.71, 131.55, 129.76, 129.35, 123.51, 115.91, 113.74,
112.34, 112.01, 101.37, 56.07, 29.08; IR (neat) 3408 (m),
2929 (m), 1585 (s), 1540 (m), 1490 (m), 1216 (s), 749 (s);
CIMS (methane) m/z: 422 (MCH), 342, 264.
4.4. Representative procedure for the synthesis of
indoles and indolenines from carboxylic acids and
organolithiums
4.4.1. Procedure E:26 synthesis of 3-heptyl-2-methylin-
dole (4l) Methyllithium in ether (0.28 mL, 0.45 mmol) was
added to a stirring ether (1.0 mL) solution at 0 8C, under
argon. A solution of nonanoic acid (38 mL, 0.22 mmol) in
ether (0.1 mL) was added over 3 min. The reaction mixture
was stirred at 0 8C for 5 min, then at rt 10 min. The reaction
mixture was then heated at 45 8C for 30 min. The resulting
heterogeneous mixture was cooled to 0 8C and phenyl-
hydrazine$HCl (96 mg, 0.67 mmol) quickly added. The
reaction mixture was stirred 5 min at 0 8C, 5 min at rt, then
concentrated to remove ether. Glacial acetic acid (0.9 mL)
added and the reaction mixture was heated to 90 8C for 3 h.
Following the extractive workup of procedure A, the pro-
duct was purified by silica gel flash column chromatography
(8:1 hexanes/ether, RfZ0.3), to afford a yellow oil (28 mg,
55%); 1H NMR (300 MHz, CDCl3) d 7.65 (br s, 1H), 7.53
(m, 1H), 7.26 (m, 1H), 7.11 (m, 2H), 2.69 (t, 2H, JZ
4.4.5. 2-Butyl-3,3-dimethylindolenine (6b). The product
was purified by silica gel flash column chromatography (8:1
hexanes/ether, RfZ0.3), to afford a yellow oil (33 mg,
66%); 1H NMR (300 MHz, CDCl3) d 7.57 (d, 1H, JZ
7.6 Hz), 7.28 (m, 2H), 7.17 (t, 1H, JZ7.3 Hz), 2.52 (t, 2H,
JZ8.2 Hz), 1.83 (p, 2H, JZ8.0 Hz) 1.45 (sextet, 2H, JZ
7.6 Hz), 1.28 (s, 6H), 0.97 (t, 3H, JZ7.3 Hz); 13C NMR
(125 MHz, CDCl3) d 191.36, 154.02, 145.81, 127.72,
125.16, 121.35, 120.19, 53.97, 28.89, 28.76, 23.40, 23.11,