Iodine → Trifluoromethyluracil

Participants

Reaction Conditions

Reaction Steps

In 73.9 ml of dimethylsulfoxide, 25.2 g of 5-trifluoromethyl-5,6-dihydrouracil was dissolved, and 2.44 g of iodine and 0.54 ml of concentrated sulfuric acid were added to obtain a uniform solution. The solution was stirred at 150° C. for 8 hours, and the resultant was cooled to room temperature, followed by adding 120 g of 3% aqueous sodium sulfite solution to reduce iodine. The resulting solution was concentrated under reduced pressure. After adding water to the obtained residue, the residue was extracted three times with ethyl acetate. The ethyl acetate layer was dried over anhydrous sodium sulfate and the obtained residue was crystallized from chloroform, and then recrystallized from 100 ml of water to obtain 14.8 g of 5-trifluoromethyluracil in the form of white needle-shaped crystals.

Provenance & Evidence