Br[C:2]1[N:6]2[CH:7]=[CH:8][C:9]([CH3:11])=[CH:10][C:5]2=[N:4][CH:3]=1.[CH3:12][O:13][C:14]1[CH:15]=[C:16](B(O)O)[CH:17]=[CH:18][CH:19]=1.O>COCCOC.C(=O)([O-])[O-].[Na+].[Na+]>[CH3:12][O:13][C:14]1[CH:19]=[C:18]([C:2]2[N:6]3[CH:7]=[CH:8][C:9]([CH3:11])=[CH:10][C:5]3=[N:4][CH:3]=2)[CH:17]=[CH:16][CH:15]=1A mixture of 3-bromo-7-methylimidazo[1,2-α]pyridine (18.0 g, 86 mmol) and 3-methoxyphenylboronic acid (17.0 g, 112 mmol) in 1,2-dimethoxyethane (250 ml) and sodium carbonate (120 ml of a 2M aqueous solution) was degassed for 25 minutes. Tetrakis(triphenylphosphine)pallidum(0) (500 mg, 0.4 mmol) was then added and the mixture heated at reflux for 17 hours. After cooling to ambient temperature the reaction was poured into water (400 ml), extracted with ethyl acetate (3×400 ml) and the combined organics dried over anhydrous magnesium sulphate. Filtration and evaporation to dryness afforded 3-(3-methoxyphenyl)-7-methylimidazo[1,2-α]pyridine as a colourless oil (19 g, 93%). 1H NMR (360 MHz, CDC3) δH 2.40 (3H, s), 3.84 (3H, s), 6.63-6.65 (1H, m), 6.91-6.95 (1H, m), 7.05-7.07 (1H, m), 7.10-7.12 (1H, m), 7.30-7.38 (1H, m), 7.42 (1H, s), 7.66 (1H, s), 8.22 (1H, d, J 7); m/z (ES+) 239 (M++H).
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