The Journal of Organic Chemistry
Page 6 of 14
1
2
3
4
5
6
7
8
9
8.17 – 8.12 (m, 1H), 7.69 (dd, J = 7.4, 1.9 Hz, 1H), 7.55 (d, J =
Hz, 1H), 3.13 (d, J = 4.7 Hz, 1H), 3.04 – 2.93 (m, 1H), 2.43 (s,
3H), 1.87 – 1.55 (m, 5H), 1.30 – 1.11 (m, 5H).
9.1 Hz, 1H), 7.47 (dd, J = 7.8, 1.4 Hz, 1H), 7.34 (tdd, J = 14.6,
7.2, 1.4 Hz, 2H), 7.13 (ddd, J = 9.0, 6.7, 1.3 Hz, 1H), 6.80 (td,
J = 6.8, 1.0 Hz, 1H), 3.30 (d, J = 7.3 Hz, 1H), 2.67 (qd, J = 9.9,
3.8 Hz, 1H), 1.71 – 1.43 (m, 5H), 1.11 – 0.95 (m, 5H).
N-Cyclohexyl-2-(o-tolyl)imidazo[1,2-a]pyridin-3-amine (1l):
15d
o
1
Yellow solid, m.p. 108 – 109 C, 356 mg, 82% yield; H
NMR (400 MHz, CDCl3) δ 8.10 (dt, J = 6.9, 1.1 Hz, 1H), 7.53
(dt, J = 9.0, 1.0 Hz, 1H), 7.35 (d, J = 7.1 Hz, 1H), 7.32 – 7.28
(m, 2H), 7.24 (ddd, J = 5.9, 5.1, 3.5 Hz, 1H), 7.13 (ddd, J = 9.0,
6.7, 1.3 Hz, 1H), 6.80 (td, J = 6.8, 1.1 Hz, 1H), 3.00 (s, 1H),
2.73 (s, 1H), 2.34 (s, 3H), 2.34 (s, 3H), 1.74 – 1.64 (m, 2H),
1.59 (dd, J = 9.4, 4.0 Hz, 2H), 1.52 – 1.45 (m, 1H), 1.17 – 0.88
(m, 5H).
2-(4-Bromophenyl)-N-cyclohexylimidazo[1,2-a]pyridin-3-
amine (1e): Pale yellow solid, m.p. 164 – 166 °C (Lit.15b 166-
1
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
168 °C), 384 mg, 74% yield; H NMR (400 MHz, CDCl3) δ
8.07 (d, J = 6.9 Hz, 1H), 7.97 (d, J = 8.6 Hz, 2H), 7.56 (d, J =
8.6 Hz, 2H), 7.53 (d, J = 9.1 Hz, 1H), 7.14 (ddd, J = 9.0, 6.7,
1.3 Hz, 1H), 6.79 (td, J = 6.8, 1.1 Hz, 1H), 3.04 (d, J = 4.8 Hz,
1H), 2.93 (ddd, J = 14.4, 10.0, 4.6 Hz, 1H), 1.80 – 1.65 (m, 2H),
1.58 (m, 5H), 1.20 (m, 5H).
N-Cyclohexyl-2-(4-methoxyphenyl)imidazo[1,2-a]pyridin-3-
amine (1m): White solid, m.p. 153 – 155 °C (Lit. 15d 154 °C),
358 mg, 79% yield; 1H NMR (400 MHz, CDCl3) δ 8.06 (d, J =
6.8 Hz, 1H), 7.98 (d, J = 8.9 Hz, 2H), 7.50 (d, J = 9.0 Hz, 1H),
7.13 – 7.06 (m, 1H), 6.98 (d, J = 8.7 Hz, 2H), 6.74 (t, J = 6.7
Hz, 1H), 3.84 (s, 3H), 3.05 (d, J = 4.3 Hz, 1H), 2.94 (dt, J =
13.5, 6.9 Hz, 1H), 1.79 (d, J = 10.7 Hz, 2H), 1.67 (d, J = 4.6 Hz,
2H), 1.56 (s, 1H), 1.26 – 1.11 (m, 5H).
2-(3-Bromophenyl)-N-cyclohexylimidazo[1,2-a]pyridin-3-
amine (1f): Brown solid, m.p. 76 – 78 °C (Lit. 15b 79 – 81 °C),
372 mg, 71% yield; 1H NMR (400 MHz, CDCl3) δ 8.29 (t, J =
1.7 Hz, 1H), 8.08 (dt, J = 6.9, 1.1 Hz, 1H), 8.04 – 7.97 (m, 1H),
7.54 (d, J = 9.1 Hz, 1H), 7.43 (ddd, J = 7.9, 1.9, 1.0 Hz, 1H),
7.30 (d, J = 7.9 Hz, 1H), 7.15 (ddd, J = 9.0, 6.7, 1.3 Hz, 1H),
6.80 (td, J = 6.8, 1.0 Hz, 1H), 3.05 (d, J = 4.8 Hz, 1H), 3.01 –
2.90 (m, 1H), 1.86 – 1.56 (m, 5H), 1.31 – 1.05 (m, 5H).
N-Cyclohexyl-2-(3-methoxyphenyl)imidazo[1,2-a]pyridin-3-
amine (1n): White solid, m.p. 151 – 152 °C ( Lit.15d 153 –
1
2-(2-Bromophenyl)-N-cyclohexylimidazo[1,2-a]pyridin-3-
155 °C), 382 mg, 84% yield; H NMR (400 MHz, CDCl3) δ
amine (1g): Brown solid, m.p. 139 – 141°C (Lit.15c 140 –
8.08 (d, J = 6.9 Hz, 1H), 7.65 (dd, J = 2.4, 1.6 Hz, 1H), 7.63 –
7.59 (m, 1H), 7.53 (d, J = 9.0 Hz, 1H), 7.35 (t, J = 7.9 Hz, 1H),
7.11 (ddd, J = 9.0, 6.7, 1.2 Hz, 1H), 6.87 (ddd, J = 8.2, 2.6, 0.7
Hz, 1H), 6.76 (td, J = 6.8, 1.0 Hz, 1H), 3.89 (s, 3H), 3.13 (d, J
= 5.0 Hz, 1H), 3.02 – 2.92 (m, 1H), 1.67 (m, 5H), 1.30 – 1.07
(m, 5H).
1
142 °C), 365 mg, 70% yield; H NMR (400 MHz, CDCl3) δ
8.15 (dt, J = 6.9, 1.1 Hz, 1H), 7.64 (ddd, J = 12.2, 7.9, 1.4 Hz,
2H), 7.57 – 7.52 (m, 1H), 7.40 (td, J = 7.5, 1.2 Hz, 1H), 7.27 –
7.20 (m, 1H), 7.13 (ddd, J = 9.0, 6.7, 1.3 Hz, 1H), 6.80 (td, J =
6.8, 1.0 Hz, 1H), 3.29 (d, J = 7.0 Hz, 1H), 2.69 – 2.66 (m, 1H),
1.67 – 1.45 (m, 1H), 1.13 – 0.93 (m, 5H).
N-Cyclohexyl-2-(2-methoxyphenyl)imidazo[1,2-a]pyridin-3-
1
N-Cyclohexyl-2-(4-fluorophenyl)imidazo[1,2-a]pyridin-3-
amine (1o): Viscous brown oil, 345 mg, 76% yield; H NMR
amine (1h): White solid, m.p. 165 – 167°C ( Lit.15b 167 –
(400 MHz, CDCl3) δ 8.10 (dd, J = 6.8, 1.1 Hz, 1H), 7.87 (dd, J
= 7.6, 1.4 Hz, 1H), 7.55 (dd, J = 9.0, 1.0 Hz, 1H), 7.34 (ddd, J
= 8.9, 3.3, 1.6 Hz, 1H), 7.15 – 7.05 (m, 2H), 7.00 (dd, J = 8.3,
0.8 Hz, 1H), 6.79 – 6.73 (m, 1H), 3.96 (d, J = 8.3 Hz, 1H), 3.88
(d, J = 2.0 Hz, 3H), 2.70 – 2.58 (m, 1H), 1.72 –1.47 (m, 5H),
1.14 – 0.95 (m, 5H).
1
169 °C), 497 mg, 91% yield; H NMR (400 MHz, CDCl3) δ
8.11 – 8.07 (m, 1H), 8.07 – 8.01 (m, 2H), 7.53 (dd, J = 9.0, 0.9
Hz, 1H), 7.18 – 7.09 (m, 3H), 6.83 – 6.76 (m, 1H), 3.06 (d, J =
4.4 Hz, 1H), 2.99 – 2.88 (m, 1H), 1.80 (d, J = 11.0 Hz, 2H),
1.69 (d, J = 4.1 Hz, 2H), 1.58 (s, 1H), 1.14 – 1.28 (m, 5H.
N-Cyclohexyl-2-(2-nitrophenyl)imidazo[1,2-a]pyridin-3-
4-(3-(Cyclohexylamino)imidazo[1,2-a]pyridin-2-yl)-2-meth-
oxyphenol (1p): 15e White solid, m.p. 204 – 205 °C, 398 mg, 85%
yield; 1H NMR (400 MHz, CDCl3) δ 8.11 (d, J = 6.8 Hz, 1H),
7.70 (d, J = 1.8 Hz, 1H), 7.58 – 7.46 (m, 2H), 7.17 – 7.10 (m,
1H), 6.98 (d, J = 8.2 Hz, 1H), 6.80 (td, J = 6.8, 0.8 Hz, 1H),
6.09 (s, 1H), 3.12 (s, 1H), 2.99 (dt, J = 13.3, 6.8 Hz, 1H), 1.83
– 1.56 (m, 3H), 1.27-1.14 (m, 5H).
amine(1i): 15c Yellow solid, m.p. 167 – 169 °C, 412 mg, 86%
1
yield; H NMR (400 MHz, CDCl3) δ 9.07 (t, J = 1.9 Hz, 1H),
8.52 (d, J = 7.8 Hz, 1H), 8.15 (ddd, J = 8.2, 2.2, 0.8 Hz, 1H),
8.10 (d, J = 6.9 Hz, 1H), 7.61 (t, J = 8.0 Hz, 1H), 7.56 (d, J =
9.1 Hz, 1H), 7.19 (ddd, J = 9.0, 6.7, 1.1 Hz, 1H), 6.84 (td, J =
6.8, 0.9 Hz, 1H), 3.08 (d, J = 4.5 Hz, 1H), 3.00 (td, J = 10.4, 5.4
Hz, 1H), 1.88 – 1.60 (m, 5H), 1.33 – 1.18 (m, 5H).
N-Cyclohexyl-2-ethylimidazo[1,2-a]pyridin-3-amine
(1t):
N-Cyclohexyl-2-(p-tolyl)imidazo[1,2-a]pyridin-3-amine (1j):
White solid, m.p. 162 – 164 °C ( Lit. 15d 166 – 169 °C), 398
mg, 92% yield; 1H NMR (400 MHz, CDCl3) δ 8.12 (d, J = 6.8
Hz, 1H), 7.94 (d, J = 8.2 Hz, 2H), 7.57 (d, J = 9.0 Hz, 1H), 7.30
– 7.25 (d, J = 8.2 Hz, 2H), 7.17 – 7.10 (m, 1H), 6.79 (t, J = 6.7
Hz, 1H), 3.14 (s, 1H), 3.03 – 2.90 (m, 1H), 1.81 – 1.58 (m, 1H),
1.28 – 1.13 (m, 5H).
Colorless crystal, m.p. 139 – 141 °C ( Lit. 15f 140 – 142 °C),
293 mg, 83% yield; 1H NMR (400 MHz, CDCl3) δ 8.22 (d, J =
6.5 Hz, 1H), 7.22 – 7.15 (m, 1H), 6.97 (t, J = 6.8 Hz, 1H), 3.17
(s, 1H), 3.11 (q, J = 7.6 Hz, 3H), 2.90 (s, 3H), 2.22 – 1.92 (m,
5H), 1.67 (t, J = 7.6 Hz, 3H), 1.59 – 1.48 (m, 5H).
N-Cyclohexyl-2-isopropylimidazo[1,2-a]pyridin-3-amine (1u):
1
Yellow viscose oil, 284 mg, 78% yield; H NMR (400 MHz,
N-Cyclohexyl-2-(m-tolyl)imidazo[1,2-a]pyridin-3-amine (1k):
CDCl3) δ 5.28 (s, 1H), 3.76 (tdt, J = 12.1, 8.1, 3.9 Hz, 1H), 2.28
(dd, J = 13.8, 6.9 Hz, 1H), 1.94 – 1.86 (m, 2H), 1.72 – 1.67 (m,
2H), 1.65 – 1.58 (m, 1H), 1.44 – 1.29 (m, 3H), 1.19 (dd, J = 7.6,
4.0 Hz, 1H), 1.15 (s, 3H), 1.13 (s, 3H), 1.12 – 0.97 (m, 2H).
15d
o
1
Yellow solid, m.p. 114 – 115 C, 377 mg, 87% yield; H
NMR (400 MHz, CDCl3) δ 8.12 (dd, J = 6.9, 1.0 Hz, 1H), 7.91
(s, 1H), 7.81 (d, J = 7.8 Hz, 1H), 7.55 (d, J = 9.0 Hz, 1H), 7.34
(t, J = 7.6 Hz, 1H), 7.17 – 7.09 (m, 2H), 6.78 (td, J = 6.8, 1.0
ACS Paragon Plus Environment