Water → Trifluoroacetic acid

Participants

Reaction Steps

In 10 ml of a mixed solution of anhydrous trifluoroacetic acid: water=9:1 was suspended 0.74 g (2 mmole) of 1-[6-(t-butoxycarbonylamino)-n-hexylcarbamoyl]-5-fluorouracil under ice-cooling. When the suspension was stirred under ice-cooling, it was gradually dissolved to form a uniform solution. After stirring about one hour, the mixture was condensed under reduced pressure. To the residue was added 50 ml of toluene, and azeotropically dehydrated by reduced pressure condensation. To the residue was again added 50 ml of toluene, the same procedure as mentioned above was carried out. When about 100 ml of chloroform was added to the residue and allowed to stand overnight, the residue crystallized. Chloroform was removed under reduced pressure and the residue was recrystallized from 20 ml of ethanol. The title compound can be obtained with an amount of 0.29 g (Yield: 37.5%) as a salt of trifluoroacetic acid with a molar ratio of 1:1.

Provenance & Evidence