反应详情

温度

85 °C

To a solution of 1-butyrimidoylamino-1H-pyrrole-2-carboxylic acid ethyl ester (7.6 g, 34 mmol) in dioxane (70 mL) at room temperature was added cesium carbonate (21.7 g, 66.7 mmol). The mixture was heated at 85° C. for 45 min and then benzyl bromide (4.2 mL, 35 mmol) was added. The reaction was stirred at 85° C. for 1 h. After cooling to room temperature, the reaction was filtered through a plug of silica gel and concentrated in vacuo. Purification of the crude product by flash column chromatography (SiO2, EtOAc/Hexane 1:4) gave the title compound as a white solid (8.9 g, 99%): 1H NMR (CDCl3) δ 7.22 (m, 6H), 6.96 (m, 1H), 6.43 (m, 1H), 5.17 (s, 2H), 2.47 (q, 2H, J=7.44 Hz), 1.63 (m, 2H), 0.88 (t, 3H, J=7.4 Hz); 13C NMR (CDCl3) δ 155.7, 149.7, 136.9, 129.3, 128.0, 126.8, 121.0, 118.4, 110.9, 108.8, 45.2, 34.6, 20.5, 14.1; MS (ESI+) 268.12 (M++H).

1. temperatureAfter cooling to room temperature
2. filtrationthe reaction was filtered through a plug of silica gel
3. concentrationconcentrated in vacuo
4. customPurification of the crude product by flash column chromatography (SiO2, EtOAc/Hexane 1:4)