Acetic Anhydride → 2-(4-Acetylamino-3-fluorophenyl)-5-amino-6,8-difluoro-4H-1-benzopyran-4-one

Participants

Reaction Steps

1.66 g of Compound 26 was dissolved in 20 ml of pyridine, the solution was cooled on ice, 0.46 ml of acetic anhydride was added and the mixture was stirred at room temperature for 2.2 hours. Then, the reaction solution was added to 100 ml of ice water and the precipitated crystals were collected by filtration to give 1.82 g (96%) of Compound 27.

Provenance & Evidence