反应详情

In 2 ml of ethyl acetate was dissolved 100 mg of ethyl 2-[2-(2,4-difluorophenylamino)-5-fluoro-6-hydroxynicotinoyl]acetate, and a diethyl ether solution containing 15 mg of diazomethane was added thereto with ice-cooling, after which the resulting mixture was subjected to reaction at room temperature for 30 minutes. Subsequently, acetic acid was added to the reaction mixture until foaming was not caused in the reaction mixture. The solvent was then removed by distillation under reduced pressure and to the crystalline material thus obtained was added 2 ml of diisopropyl ether, after which crystals were collected by filtration to obtain 80 mg (yield 77.0%) of ethyl 2-[2-(2,4-difluorophenylamino)-5-fluoro-6-methoxynicotinoyl]acetate. The physical properties of this compound were identical with those of the compound obtained in Example 18.

1. additionwas added
2. temperaturewith ice-cooling
3. customafter which the resulting mixture was subjected to reaction at room temperature for 30 minutes
4. customThe solvent was then removed by distillation under reduced pressure and to the crystalline material
5. customthus obtained
6. filtrationafter which crystals were collected by filtration