830346-47-9

830346-46-8

1694-31-1

830346-47-9

Using 1-(2-fluoro-6-(trifluoromethyl)benzyl)urea (2.568 g, 10.9 mmol) and tert-butyl acetoacetate (5.0 g) in toluene (125 mL), the mixture was briefly heated to reflux using a Dean-Stark splitter. Subsequently, tert-butyl acetoacetate (5.0 g) was added and heating to reflux was continued for 4 hours. Next, p-toluenesulfonic acid monohydrate (2.82 g, 14.8 mmol) was added and reflux was continued for 1 hour. Upon completion of the reaction, toluene was replaced with isopropanol (i-PrOH) and the volume of the solution was concentrated to approximately 30 mL. The solution was stirred overnight at room temperature to crystallize the product. The crystallized product was collected by filtration and washed with a small amount of isopropanol to give 2.01 g of 1-(2-fluoro-6-(trifluoromethyl)benzyl)-6-methylpyrimidine-2,4(1H,3H)-dione in 63% yield. The product was analyzed by LCMS (ESI) at m/z 303.0 (MH+).