反应详情

3.03 g (8.70 mmol) of Compound 27 obtained in Example 27 was dissolved in 200 ml of dimethylformamide, 109 mg of dimethylaminopyridine and 3.0 ml of di-tert-butyl carbonate were added and the mixture was stirred at room temperature for 2 hours. Water was added to the reaction solution and the precipitated crystals were collected by filtration to give 3.44 g (88%) of 2-[4-[N-acetyl-N-(tert-butoxycarbonyl)amino]-3-fluorophenyl]-5-amino-6,8-difluoro-4H-1-benzopyran-4-one.

1. filtrationthe precipitated crystals were collected by filtration