The Journal of Organic Chemistry
Note
2-Phenylimidazo[2,1-a]isoquinoline (5a).20
7.53 (t, J = 7.5 Hz, 1H), 7.60−7.66 (m, 2H), 7.75 (s, 2H), 7.81 (d, J =
7 Hz, 1H), 7.86 (s, 1H), 8.71 (d, J = 8 Hz, 1H). 13C{1H} NMR
(125 MHz, CDCl3): δ 21.4, 109.8, 112.9, 122.8, 123.4, 123.7, 126.4,
126.8, 128.0, 128.3, 128.5, 129.4, 133.7, 138.2, 143.1, 144.0. Mass
[M + H]+ = 259.23.
1
2-(3-Chlorophenyl)imidazo[2,1-a]isoquinoline (5g).
Yield: 71% (52.0 mg). H NMR (500 MHz, CDCl3): δ 6.97 (d, J =
7 Hz, 1H), 7.31 (t, J = 7.5 Hz, 1H), 7.44 (t, J = 7.5 Hz, 2H), 7.52−7.55
(m, 1H), 7.60−7.66 (m, 2H), 7.76 (s, 1H), 7.82 (d, J = 7.5 Hz, 1H),
7.98 (d, J = 7 Hz, 2H), 8.71 (d, J = 8 Hz, 1H). 13C{1H} NMR
(125 MHz, CDCl3): δ 109.8, 113.0, 122.8, 123.4, 123.7, 125.8, 127.5,
128.0, 128.6, 129.4, 133.9, 143.2, 143.9. Mass [M + H]+ = 245.16.
2-(p-Tolyl)imidazo[2,1-a]isoquinoline (5b).
Light-brown crystalline solid, observed melting point 150.7 °C. Yield:
1
66% (55.0 mg). H NMR (500 MHz, CDCl3): δ 7.01 (d, J = 7 Hz,
1H), 7.26 (d, J = 8 Hz, 1H), 7.35 (t, J = 7.5 Hz, 1H), 7.56 (t, J = 8 Hz,
1H), 7.64 (t, J = 7 Hz, 1H), 7.67 (d, J = 7.5 Hz, 1H), 7.78 (s, 1H),
7.84 (d, J = 7 Hz, 2H), 8.00 (s, 1H), 8.69 (d, J = 8 Hz, 1H). 13C{1H}
NMR (125 MHz, CDCl3): δ 110.2, 113.3, 122.8, 123.4, 123.7, 123.8,
125.8, 126.9, 127.4, 128.2, 128.3, 129.4, 129.9, 134.6, 135.8, 142.5,
143.3. HRMS: calcd for C17H12ClN2 279.0689, found 279.0681.
2-(3-Bromophenyl)imidazo[2,1-a]isoquinoline (5h).
White solid, observed melting point 149.8 °C. Yield: 68% (52.6 mg).
1H NMR (500 MHz, CDCl3): δ 2.39 (s, 3H), 7.02 (d, J = 7.5 Hz, 1H),
7.25 (m, 2H), 7.54−7.57 (m, 1H), 7.61−7.65 (m, 1H), 7.68 (d, J =
8 Hz, 1H), 7.79 (s, 1H), 7.89−7.91 (m, 3H), 8.72 (d, J = 8 Hz, 1H).
13C{1H} NMR (125 MHz, CDCl3): δ 109.4, 112.8, 122.8, 123.4,
123.7, 125.6, 126.8, 127.9, 129.3, 131.1, 137.2, 143.1, 144.0. HRMS:
calcd for C18H15N2 259.1235, found 259.1231.
Light-brown crystalline solid, observed melting point 164.3 °C. Yield:
2-(4-Chlorophenyl)imidazo[2,1-a]isoquinoline (5c).
1
74% (71.4 mg). H NMR (500 MHz, CDCl3): δ 7.01 (d, J = 7 Hz,
1H), 7.29 (d, J = 8 Hz, 1H), 7.42 (d, J = 8 Hz, 1H), 7.56 (t, J = 7.5 Hz,
1H), 7.63 (t, J = 8 Hz, 1H), 7.67 (d, J = 8 Hz, 1H), 7.77 (s, 1H), 7.84
(d, J = 7 Hz, 1H), 7.88 (d, J = 8 Hz, 1H), 8.16 (s, 1H), 8.69 (d, J =
8 Hz, 1H). 13C{1H} NMR (125 MHz, CDCl3): δ 110.2, 113.3, 122.8,
122.9, 123.4, 123.7, 124.2, 126.9, 128.2, 128.3, 128.7, 129.4, 130.1,
130.3, 136.0, 142.4, 143.3. HRMS: calcd for C17H12N2Br 323.0184,
found 323.0189.
White crystalline solid, observed melting point 189.1 °C. Yield: 76%
(63.3 mg). H NMR (500 MHz, CDCl3): δ 7.00 (d, J = 7 Hz, 1H),
1
7.38 (d, J = 8.5 Hz, 2H), 7.54−7.57 (m, 1H), 7.63 (t, J = 7 Hz, 1H),
7.67 (d, J = 7.5 Hz, 1H), 7.75 (s, 1H), 7.83 (d, J = 7 Hz, 1H), 7.91
(d, J = 8 Hz, 2H), 8.68 (d, J = 8 Hz, 1H). 13C{1H} NMR (125 MHz,
CDCl3): δ 109.8, 113.2, 122.8, 123.4, 123.6, 126.9, 127.0, 128.1, 128.2,
128.8, 129.4, 132.4, 133.1, 142.8, 143.3. HRMS: calcd for C17H12ClN2
279.0689, found 279.0685.
2-(3-Nitrophenyl)imidazo[2,1-a]isoquinoline (5i).
2-(4-Bromophenyl)imidazo[2,1-a]isoquinoline (5d).19
Yellow solid, observed melting point 188.9 °C. Yield: 69% (59.8 mg).
1H NMR (500 MHz, CDCl3): δ 7.06 (d, J = 7 Hz, 1H), 7.57−7.61
(m, 2H), 7.66 (t, J = 8 Hz, 1H), 7.70 (d, J = 8 Hz, 1H), 7.89 (d, J =
8 Hz, 2H), 8.12 (d, J = 7.5 Hz, 1H), 8.33 (d, J = 7.5 Hz, 1H), 8.69
(d, J = 8 Hz, 1H), 8.79 (s, 1H). 13C{1H} NMR (125 MHz, CDCl3):
δ 110.7, 113.7, 120.4, 122.0, 122.8, 123.4, 123.6, 127.0, 128.4, 128.5,
129.5, 131.5, 135.8, 141.5, 143.6, 148.6. HRMS: calcd for C17H12N3O2
290.0930, found 290.0926.
1
Yield: 75% (72.4 mg). H NMR (500 MHz, CDCl3): δ 7.01 (d, J =
7 Hz, 1H), 7.54−7.58 (m, 3H), 7.63 (t, J = 7.5 Hz, 1H), 7.68 (d, J =
7.5 Hz, 1H), 7.78 (s, 1H), 7.85−7.87 (m, 3H), 8.68 (d, J = 8 Hz, 1H).
13C{1H} NMR (125 MHz, CDCl3): δ 109.9, 113.3, 121.3, 122.8,
123.4, 123.7, 126.9, 127.3, 128.1, 128.2, 129.4, 131.7, 132.9, 142.8,
143.3. Mass [M + H]+ = 323.26.
2-(2-Methoxyphenyl)imidazo[2,1-a]isoquinoline (5j).
2-(4-(tert-Butyl)phenyl)imidazo[2,1-a]isoquinoline (5e).
White crystalline solid, observed melting point 150.9 °C. Yield: 48%
1
(39.4 mg). H NMR (500 MHz, CDCl3): δ 3.96 (s, 3H), 6.92 (d, J =
6.5 Hz, 1H), 6.96 (d, J = 8 Hz, 1H), 7.13 (t, J = 7.5 Hz, 1H), 7.26−
7.30 (m, 1H), 7.51 (t, J = 8 Hz, 1H), 7.58−7.64 (m, 2H), 7.82 (d, J =
7 Hz, 1H), 8.11 (s, 1H), 8.54 (dd, J1 = 9 Hz, J2 = 1.5 Hz, 1H), 8.72
(d, J = 8 Hz, 1H). 13C{1H} NMR (125 MHz, CDCl3): δ 55.2, 110.6,
112.5, 114.1, 120.9, 122.5, 122.9, 123.4, 123.6, 126.7, 127.8, 128.1,
128.5, 129.4, 139.2, 141.9, 156.4. HRMS: calcd for C18H15N2O
275.1184, found 275.1180.
White solid, observed melting point 149.2 °C. Yield: 68% (61.2 mg).
1H NMR (500 MHz, CDCl3): δ 1.36 (s, 9H), 6.95 (d, J = 7.5 Hz, 1H),
7.45 (d, J = 8 Hz, 2H), 7.53 (t, J = 7.5 Hz, 1H), 7.59−7.65 (m, 2H),
7.73 (s, 1H), 7.80 (d, J = 7 Hz, 1H), 7.90 (d, J = 8.5 Hz, 2H), 8.71
(d, J = 8 Hz, 1H). 13C{1H} NMR (125 MHz, CDCl3): δ 31.3, 34.5,
109.4, 112.8, 122.8, 123.4, 123.7, 125.5, 126.8, 127.9, 129.3, 131.1, 143.1,
144.0, 150.5. HRMS: calcd for C21H21N2 301.1705, found 301.1725.
2-(m-Tolyl)imidazo[2,1-a]isoquinoline (5f).20
2-(2-Fluorophenyl)imidazo[2,1-a]isoquinoline (5k).
White crystalline solid, observed melting point 126.9 °C. Yield: 71%
1
(55.8 mg). H NMR (500 MHz, CDCl3): δ 6.98 (d, J = 7 Hz, 1H),
7.12−7.16 (m, 1H), 7.26−7.29 (m, 2H), 7.54 (t, J = 7.5 Hz, 1H), 7.62
(t, J = 7.5 Hz, 1H), 7.65 (d, J = 7.5 Hz, 1H), 7.84 (d, J = 7 Hz, 1H),
1
Yield: 66% (51.1 mg). H NMR (500 MHz, CDCl3): δ 2.43 (s, 3H),
6.96 (d, J = 7 Hz, 1H), 7.12 (d, J = 7 Hz, 1H), 7.32 (t, J = 7.5 Hz, 1H),
G
dx.doi.org/10.1021/jo5021618 | J. Org. Chem. XXXX, XXX, XXX−XXX