反应详情

A solution of methyl 1-amino-3-chloro-1H-pyrrole-2-carboxylate (10.0 g, 57.3 mmol, WO 03/099286: Compound A of Example 9) in formamide (40 mL) was heated at 170° C. for 1 h and then at 190° C. for 1 h. Upon cooling to room temperature, the mixture solidified. The product was purified by recrystallization from ethyl acetate to give the title compound (6.53 g, 67%) as a white solid. 1H NMR (CDCl3) δ 10.24 (br s, 1H), 7.48 (d, 1H, J=3.6 Hz), 7.29 (d, 1H, J=2.8 Hz), 6.47 (d, 1H, J=2.8 Hz); MS(ESI+) m/z 170.1 (M+H)+.

1. customThe product was purified by recrystallization from ethyl acetate