反应详情

温度

40 °C

A 25 mL RB flask with a stirring bar was charged with 2-thiopheneacetic acid (2.84 g, 2 mmol), followed by anhydrous DMF (10 mL). 1,1′-Carbonyldiimidazole (3.24 g, 2 mmol) was added in one portion, giving rise to significant gas evolution. The mixture was warmed to 40° C. After 30 min, N,O-dimethylhydroxyamine hydrochloride (2.14 g, 2.2 mmol) was introduced in one portion. The mixture was allowed to stir at 23° C. for 30 min. before being diluted with sat. ammonium chloride solution (100 mL) and extracted twice with 1:1 ethyl acetate/hexanes (100 mL). The crude mixture was purified by column chromatography over silica gel (0-25% ethyl acetate/hexanes) to give N-methoxy-N-methyl-2-(2-thienyl)acetamide (1-1). 1H NMR (CDCl3, ppm) δ 7.20 (m, 1H), 6.96 (m, 2H), 3.91 (s, 2H), 3.70 (s, 3H), 3.25 (s, 3H).

1. customgiving rise to significant gas evolution
2. extractionextracted twice with 1:1 ethyl acetate/hexanes (100 mL)
3. customThe crude mixture was purified by column chromatography over silica gel (0-25% ethyl acetate/hexanes)