5-Fluorouracil → 1-Methanesulfonyl-5-fluorouracil

Participants

Reaction Conditions

Reaction Steps

2.6 g. (0.02 mole) of 5-fluorouracil and 1.52 g (0.011 mole) of anhydrous potassium carbonate were suspended in 50 ml. of dioxane and then 2.53 g (0.022 mole) of methanesulfonyl chloride in 20 ml. of dioxane was dropwise added thereto. After stirring at 80°C. for 10 hours, the reaction mixture was filtered. The filtrate was concentrated under reduced pressure and a resinous residue was obtained. The residue was dissolved in a small amount of methanol and allowed to stand at 0°C. overnight. There was obtained 1.48 g (45.4% yield) of 5-fluoro-1 -methanesulfonyluracil. Recrystallization of the product from methanol gave leaflets melting at 223°-224°C. The results of an elementary analysis thereof were well in agreement with the calculated value as follows:

Provenance & Evidence