反应详情

温度

70 °C

A mixture of ethyl 5-(3-(2-chloroethyl)ureido)-3-methylthiophene-2-carboxylate (6.11 g, 21.02 mmol) and potassium carbonate (2.91 g, 21.0 mmol) in anhydrous acetonitrile (60 mL) was stirred under nitrogen atmosphere at 70° C. for 5 h, and then was allowed to cool to ambient temperature and was partitioned between ethyl acetate (200 mL) and water (100 mL). The aqueous layer was extracted with 10% methanol in dichloromethane (2×100 mL). The combined organic layer was dried over sodium sulfate, filtered and concentrated in vacuo. The residue was triturated with 20% ethyl acetate in hexanes to afford the title compound as a cream solid in 88% yield (4.70 g): 1H NMR (300 MHz, CDCl3) δ 6.16 (s, 1H), 5.15 (br s, 1H), 4.28 (q, J=7.1 Hz, 2H), 3.97-3.89 (m, 2H), 3.71-3.64 (m, 2H), 2.50 (s, 3H), 1.34 (t, J=7.1 Hz, 3H); MS (ES+) m/z 255.2 (M+1).

1. temperatureto cool to ambient temperature
2. customwas partitioned between ethyl acetate (200 mL) and water (100 mL)
3. extractionThe aqueous layer was extracted with 10% methanol in dichloromethane (2×100 mL)
4. dry with materialThe combined organic layer was dried over sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customThe residue was triturated with 20% ethyl acetate in hexanes