反应详情

To a solution (15 ml) of 2-amino-4-methoxycarbonylbenzoic acid (3.00 g) in trifluoroacetic acid was added dropwise anhydrous trifluoroacetic acid (7 ml) at 0° C. This mixture was stirred for 1 hr. and poured into water. The crystals were collected by filtration to give 4-methoxycarbonyl-2-trifluoroacetylaminobenzoic acid (4.40 g, yield 98%). Recrystallization from hexane-ethyl acetate gave colorless prism crystals. melting point: 185–186° C.

1. filtrationThe crystals were collected by filtration