反应详情

1.21 g (3.77 mmol) of Compound 80 obtained in Example 80 (3) was dissolved in 10 mL of pyridine, 0.46 mL (3.77 mmol) of pivaloyl chloride was added under ice-cooling and the mixture was stirred at the same temperature for 1 hour. The reaction solution was poured into ice water and the precipitated crystals were collected by filtration to give 1.48 g of 5-amino-6,8-difluoro-2-(3-fluoro-4-pivaloylaminophenyl)-7-methyl-4H-1-benzopyran-4-one (yield: 97%).

1. temperaturecooling
2. filtrationthe precipitated crystals were collected by filtration