反应详情

温度

80 °C

A mixture of 1.0 g (4,5 mmol) 1-carboxymethylquinoxaline-2,3(1H,4H)-dione, 15 ml dry methanol and 0,2 ml concentrated sulfuric acid was stirred at 80° C. for 1 h. After cooling to 25° C. the reaction mixture was poured in water and made alkaline. The precipitate was filtered off and recrystallized (acetone) to give 0.22 g (21%) 1-methoxycarbonylmethylquinoxaline-2,3(1H,4H)-dione. M.p. 269° C. 1H-NMR (DMSO-d6 ): 12.0 (1H, broad s), 7.1 (4H, s), 4.9 (2H, s), 3.7 (3H, s).

1. temperatureAfter cooling to 25° C. the reaction mixture
2. filtrationThe precipitate was filtered off
3. customrecrystallized (acetone)