Synthesis of Imidazo[1,2-a]pyridines
J. Chin. Chem. Soc., Vol. 57, No. 2, 2010 155
Chem. Ber. 1990, 123, 327.
graphed on silica gel using a mixture of AcOEt-cyclohex-
ane (1:2) as eluent to give 3.
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1905.
2-Phenylimidazo[1,2-a]pyridine (3a)
Mp 131-133 °C (lit.28 mp 130-132 °C) yield 82%. IR
(KBr) n: 1630 cm-1; 1H NMR (CDCl3) d: 6.78 (dt, J = 1.2,
6.8 Hz, 1H), 7.15-7.19 (m, 1H), 7.33 (t, J = 7.2 Hz, 1H),
7.42-7.46 (m, 2H), 7.64 (dd, J = 0.8, 8.8 Hz, 1H), 7.87 (s,
1H), 7.94-7.97 (m, 2H), 8.12 (td, J = 1.2, 6.8 Hz, 1H); 13
C
NMR (100 MHz, CDCl3) d: 108.1, 112.5, 117.5, 124.8,
125.6, 126.1, 128.0, 128.4, 128.7, 129.9, 133.4, 133.5,
145.6; EI-MS m/z (relative intensity) 194 (M+), 116, 89, 78,
63, 51, 50.
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ACKNOWLEDGEMENT
We gratefully acknowledge the National Council Sci-
ence of Republic of China for financial support of this
work.
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Received November 27, 2009.
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