反应详情

温度

120 °C

Methyl crotonate (1.35 ml, 12.8 mmol), tris(dibenzylideneacetone)-dipalladium(0) (106 mg, 0.12 mmol), tri-o-tolylphosphine (1.41 g, 4.6 mmol), and triethylamine (3.22 ml, 23.1 mmol) were added to a solution of 2-amino-5-bromo pyridine (2 g, 11.6 mmol) in DMF (25 mL). The reaction mixture was heated to 120° C. in a nitrogen atmosphere overnight, then cooled to ambient temperature and diluted with ethyl acetate (50 mL). The reaction was filtered, then washed with saturated ammonium chloride solution (2×25 mL), and the organic layer dried over MgSO4 and concentrated in vacuo. The residue was then purified by flash column (2% methanol in dichloromethane) to give 3-(6-amino-pyridin-3-yl)-but-2-enoic acid methyl ester as a yellow solid (904.7 mg, 41%). 1H NMR (250 MHz, DMSO): δ 8.22 (d, 1H, J=3.1), 7.68 (dd, 1H, J=7.5, J=3.1), 6.46 (d, 1H, J=7.5), 6.40 (bs, 2H), 6.11 (d, 1H, J=0.62), 3.65 (s, 3H), 2.48 (d, 3H, J=0.62). MS [EI+] 193 (M+H)+.

1. temperaturecooled to ambient temperature
2. filtrationThe reaction was filtered
3. washwashed with saturated ammonium chloride solution (2×25 mL)
4. dry with materialthe organic layer dried over MgSO4
5. concentrationconcentrated in vacuo
6. customThe residue was then purified by flash column (2% methanol in dichloromethane)