反应详情

温度

100 °C

Under a nitrogen atmosphere, to 3-cyclopropyl-1-(2-fluoro-4-iodo-phenyl)-6-methylamino-1H-pyrimidine-2,4-dione 52 (34.4 g) and 2-methyl-malonic acid 54 (15.2 g) was added acetic anhydride (34.4 ml), and the mixture was stirred with heating at 100° C. for 3 hrs. After allowing to cool to 50° C., acetone (68.8 ml) was added dropwise, and the mixture was stirred as it was for 30 min. Water (172 ml) was further added dropwise, and the mixture was stirred for 1 hr. After allowing to cool to room temperature with stirring, the precipitated crystals were collected by filtration and dried to give crude crystals (37.7 g, LC purity 91%) of 3-cyclopropyl-1-(2-fluoro-4-iodo-phenyl)-5-hydroxy-6,8-dimethyl-1H,8H-pyrido[2,3-d]pyrimidine-2,4,7-trione 55. Isopropanol (92.0 ml) was added to the obtained crude crystals (30.7 g), and the mixture was stirred at room temperature for 4 hrs. The crystals were collected by filtration and dried to give 3-cyclopropyl-1-(2-fluoro-4-iodo-phenyl)-5-hydroxy-6,8-dimethyl-1H,8H-pyrido[2,3-d]pyrimidine-2,4,7-trione 55 (25.9 g, yield from 76, 58%) as pale-yellow crystals.

1. temperatureto cool to 50° C.
2. stirringthe mixture was stirred as it
3. stirringthe mixture was stirred for 1 hr
4. temperatureto cool to room temperature
5. stirringwith stirring
6. filtrationthe precipitated crystals were collected by filtration
7. customdried